| /** |
| * Copyright (C) 2009 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.internal.util; |
| |
| import android.compat.annotation.UnsupportedAppUsage; |
| import android.os.Build; |
| import android.os.Handler; |
| import android.os.HandlerThread; |
| import android.os.Looper; |
| import android.os.Message; |
| import android.text.TextUtils; |
| import android.util.Log; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| |
| import java.io.FileDescriptor; |
| import java.io.PrintWriter; |
| import java.util.ArrayList; |
| import java.util.Calendar; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.Vector; |
| |
| /** |
| * {@hide} |
| * |
| * <p>The state machine defined here is a hierarchical state machine which processes messages |
| * and can have states arranged hierarchically.</p> |
| * |
| * <p>A state is a <code>State</code> object and must implement |
| * <code>processMessage</code> and optionally <code>enter/exit/getName</code>. |
| * The enter/exit methods are equivalent to the construction and destruction |
| * in Object Oriented programming and are used to perform initialization and |
| * cleanup of the state respectively. The <code>getName</code> method returns the |
| * name of the state; the default implementation returns the class name. It may be |
| * desirable to have <code>getName</code> return the state instance name instead, |
| * in particular if a particular state class has multiple instances.</p> |
| * |
| * <p>When a state machine is created, <code>addState</code> is used to build the |
| * hierarchy and <code>setInitialState</code> is used to identify which of these |
| * is the initial state. After construction the programmer calls <code>start</code> |
| * which initializes and starts the state machine. The first action the StateMachine |
| * is to the invoke <code>enter</code> for all of the initial state's hierarchy, |
| * starting at its eldest parent. The calls to enter will be done in the context |
| * of the StateMachine's Handler, not in the context of the call to start, and they |
| * will be invoked before any messages are processed. For example, given the simple |
| * state machine below, mP1.enter will be invoked and then mS1.enter. Finally, |
| * messages sent to the state machine will be processed by the current state; |
| * in our simple state machine below that would initially be mS1.processMessage.</p> |
| <pre> |
| mP1 |
| / \ |
| mS2 mS1 ----> initial state |
| </pre> |
| * <p>After the state machine is created and started, messages are sent to a state |
| * machine using <code>sendMessage</code> and the messages are created using |
| * <code>obtainMessage</code>. When the state machine receives a message the |
| * current state's <code>processMessage</code> is invoked. In the above example |
| * mS1.processMessage will be invoked first. The state may use <code>transitionTo</code> |
| * to change the current state to a new state.</p> |
| * |
| * <p>Each state in the state machine may have a zero or one parent states. If |
| * a child state is unable to handle a message it may have the message processed |
| * by its parent by returning false or NOT_HANDLED. If a message is not handled by |
| * a child state or any of its ancestors, <code>unhandledMessage</code> will be invoked |
| * to give one last chance for the state machine to process the message.</p> |
| * |
| * <p>When all processing is completed a state machine may choose to call |
| * <code>transitionToHaltingState</code>. When the current <code>processingMessage</code> |
| * returns the state machine will transfer to an internal <code>HaltingState</code> |
| * and invoke <code>halting</code>. Any message subsequently received by the state |
| * machine will cause <code>haltedProcessMessage</code> to be invoked.</p> |
| * |
| * <p>If it is desirable to completely stop the state machine call <code>quit</code> or |
| * <code>quitNow</code>. These will call <code>exit</code> of the current state and its parents, |
| * call <code>onQuitting</code> and then exit Thread/Loopers.</p> |
| * |
| * <p>In addition to <code>processMessage</code> each <code>State</code> has |
| * an <code>enter</code> method and <code>exit</code> method which may be overridden.</p> |
| * |
| * <p>Since the states are arranged in a hierarchy transitioning to a new state |
| * causes current states to be exited and new states to be entered. To determine |
| * the list of states to be entered/exited the common parent closest to |
| * the current state is found. We then exit from the current state and its |
| * parent's up to but not including the common parent state and then enter all |
| * of the new states below the common parent down to the destination state. |
| * If there is no common parent all states are exited and then the new states |
| * are entered.</p> |
| * |
| * <p>Two other methods that states can use are <code>deferMessage</code> and |
| * <code>sendMessageAtFrontOfQueue</code>. The <code>sendMessageAtFrontOfQueue</code> sends |
| * a message but places it on the front of the queue rather than the back. The |
| * <code>deferMessage</code> causes the message to be saved on a list until a |
| * transition is made to a new state. At which time all of the deferred messages |
| * will be put on the front of the state machine queue with the oldest message |
| * at the front. These will then be processed by the new current state before |
| * any other messages that are on the queue or might be added later. Both of |
| * these are protected and may only be invoked from within a state machine.</p> |
| * |
| * <p>To illustrate some of these properties we'll use state machine with an 8 |
| * state hierarchy:</p> |
| <pre> |
| mP0 |
| / \ |
| mP1 mS0 |
| / \ |
| mS2 mS1 |
| / \ \ |
| mS3 mS4 mS5 ---> initial state |
| </pre> |
| * <p>After starting mS5 the list of active states is mP0, mP1, mS1 and mS5. |
| * So the order of calling processMessage when a message is received is mS5, |
| * mS1, mP1, mP0 assuming each processMessage indicates it can't handle this |
| * message by returning false or NOT_HANDLED.</p> |
| * |
| * <p>Now assume mS5.processMessage receives a message it can handle, and during |
| * the handling determines the machine should change states. It could call |
| * transitionTo(mS4) and return true or HANDLED. Immediately after returning from |
| * processMessage the state machine runtime will find the common parent, |
| * which is mP1. It will then call mS5.exit, mS1.exit, mS2.enter and then |
| * mS4.enter. The new list of active states is mP0, mP1, mS2 and mS4. So |
| * when the next message is received mS4.processMessage will be invoked.</p> |
| * |
| * <p>Now for some concrete examples, here is the canonical HelloWorld as a state machine. |
| * It responds with "Hello World" being printed to the log for every message.</p> |
| <pre> |
| class HelloWorld extends StateMachine { |
| HelloWorld(String name) { |
| super(name); |
| addState(mState1); |
| setInitialState(mState1); |
| } |
| |
| public static HelloWorld makeHelloWorld() { |
| HelloWorld hw = new HelloWorld("hw"); |
| hw.start(); |
| return hw; |
| } |
| |
| class State1 extends State { |
| @Override public boolean processMessage(Message message) { |
| log("Hello World"); |
| return HANDLED; |
| } |
| } |
| State1 mState1 = new State1(); |
| } |
| |
| void testHelloWorld() { |
| HelloWorld hw = makeHelloWorld(); |
| hw.sendMessage(hw.obtainMessage()); |
| } |
| </pre> |
| * <p>A more interesting state machine is one with four states |
| * with two independent parent states.</p> |
| <pre> |
| mP1 mP2 |
| / \ |
| mS2 mS1 |
| </pre> |
| * <p>Here is a description of this state machine using pseudo code.</p> |
| <pre> |
| state mP1 { |
| enter { log("mP1.enter"); } |
| exit { log("mP1.exit"); } |
| on msg { |
| CMD_2 { |
| send(CMD_3); |
| defer(msg); |
| transitionTo(mS2); |
| return HANDLED; |
| } |
| return NOT_HANDLED; |
| } |
| } |
| |
| INITIAL |
| state mS1 parent mP1 { |
| enter { log("mS1.enter"); } |
| exit { log("mS1.exit"); } |
| on msg { |
| CMD_1 { |
| transitionTo(mS1); |
| return HANDLED; |
| } |
| return NOT_HANDLED; |
| } |
| } |
| |
| state mS2 parent mP1 { |
| enter { log("mS2.enter"); } |
| exit { log("mS2.exit"); } |
| on msg { |
| CMD_2 { |
| send(CMD_4); |
| return HANDLED; |
| } |
| CMD_3 { |
| defer(msg); |
| transitionTo(mP2); |
| return HANDLED; |
| } |
| return NOT_HANDLED; |
| } |
| } |
| |
| state mP2 { |
| enter { |
| log("mP2.enter"); |
| send(CMD_5); |
| } |
| exit { log("mP2.exit"); } |
| on msg { |
| CMD_3, CMD_4 { return HANDLED; } |
| CMD_5 { |
| transitionTo(HaltingState); |
| return HANDLED; |
| } |
| return NOT_HANDLED; |
| } |
| } |
| </pre> |
| * <p>The implementation is below and also in StateMachineTest:</p> |
| <pre> |
| class Hsm1 extends StateMachine { |
| public static final int CMD_1 = 1; |
| public static final int CMD_2 = 2; |
| public static final int CMD_3 = 3; |
| public static final int CMD_4 = 4; |
| public static final int CMD_5 = 5; |
| |
| public static Hsm1 makeHsm1() { |
| log("makeHsm1 E"); |
| Hsm1 sm = new Hsm1("hsm1"); |
| sm.start(); |
| log("makeHsm1 X"); |
| return sm; |
| } |
| |
| Hsm1(String name) { |
| super(name); |
| log("ctor E"); |
| |
| // Add states, use indentation to show hierarchy |
| addState(mP1); |
| addState(mS1, mP1); |
| addState(mS2, mP1); |
| addState(mP2); |
| |
| // Set the initial state |
| setInitialState(mS1); |
| log("ctor X"); |
| } |
| |
| class P1 extends State { |
| @Override public void enter() { |
| log("mP1.enter"); |
| } |
| @Override public boolean processMessage(Message message) { |
| boolean retVal; |
| log("mP1.processMessage what=" + message.what); |
| switch(message.what) { |
| case CMD_2: |
| // CMD_2 will arrive in mS2 before CMD_3 |
| sendMessage(obtainMessage(CMD_3)); |
| deferMessage(message); |
| transitionTo(mS2); |
| retVal = HANDLED; |
| break; |
| default: |
| // Any message we don't understand in this state invokes unhandledMessage |
| retVal = NOT_HANDLED; |
| break; |
| } |
| return retVal; |
| } |
| @Override public void exit() { |
| log("mP1.exit"); |
| } |
| } |
| |
| class S1 extends State { |
| @Override public void enter() { |
| log("mS1.enter"); |
| } |
| @Override public boolean processMessage(Message message) { |
| log("S1.processMessage what=" + message.what); |
| if (message.what == CMD_1) { |
| // Transition to ourself to show that enter/exit is called |
| transitionTo(mS1); |
| return HANDLED; |
| } else { |
| // Let parent process all other messages |
| return NOT_HANDLED; |
| } |
| } |
| @Override public void exit() { |
| log("mS1.exit"); |
| } |
| } |
| |
| class S2 extends State { |
| @Override public void enter() { |
| log("mS2.enter"); |
| } |
| @Override public boolean processMessage(Message message) { |
| boolean retVal; |
| log("mS2.processMessage what=" + message.what); |
| switch(message.what) { |
| case(CMD_2): |
| sendMessage(obtainMessage(CMD_4)); |
| retVal = HANDLED; |
| break; |
| case(CMD_3): |
| deferMessage(message); |
| transitionTo(mP2); |
| retVal = HANDLED; |
| break; |
| default: |
| retVal = NOT_HANDLED; |
| break; |
| } |
| return retVal; |
| } |
| @Override public void exit() { |
| log("mS2.exit"); |
| } |
| } |
| |
| class P2 extends State { |
| @Override public void enter() { |
| log("mP2.enter"); |
| sendMessage(obtainMessage(CMD_5)); |
| } |
| @Override public boolean processMessage(Message message) { |
| log("P2.processMessage what=" + message.what); |
| switch(message.what) { |
| case(CMD_3): |
| break; |
| case(CMD_4): |
| break; |
| case(CMD_5): |
| transitionToHaltingState(); |
| break; |
| } |
| return HANDLED; |
| } |
| @Override public void exit() { |
| log("mP2.exit"); |
| } |
| } |
| |
| @Override |
| void onHalting() { |
| log("halting"); |
| synchronized (this) { |
| this.notifyAll(); |
| } |
| } |
| |
| P1 mP1 = new P1(); |
| S1 mS1 = new S1(); |
| S2 mS2 = new S2(); |
| P2 mP2 = new P2(); |
| } |
| </pre> |
| * <p>If this is executed by sending two messages CMD_1 and CMD_2 |
| * (Note the synchronize is only needed because we use hsm.wait())</p> |
| <pre> |
| Hsm1 hsm = makeHsm1(); |
| synchronize(hsm) { |
| hsm.sendMessage(obtainMessage(hsm.CMD_1)); |
| hsm.sendMessage(obtainMessage(hsm.CMD_2)); |
| try { |
| // wait for the messages to be handled |
| hsm.wait(); |
| } catch (InterruptedException e) { |
| loge("exception while waiting " + e.getMessage()); |
| } |
| } |
| </pre> |
| * <p>The output is:</p> |
| <pre> |
| D/hsm1 ( 1999): makeHsm1 E |
| D/hsm1 ( 1999): ctor E |
| D/hsm1 ( 1999): ctor X |
| D/hsm1 ( 1999): mP1.enter |
| D/hsm1 ( 1999): mS1.enter |
| D/hsm1 ( 1999): makeHsm1 X |
| D/hsm1 ( 1999): mS1.processMessage what=1 |
| D/hsm1 ( 1999): mS1.exit |
| D/hsm1 ( 1999): mS1.enter |
| D/hsm1 ( 1999): mS1.processMessage what=2 |
| D/hsm1 ( 1999): mP1.processMessage what=2 |
| D/hsm1 ( 1999): mS1.exit |
| D/hsm1 ( 1999): mS2.enter |
| D/hsm1 ( 1999): mS2.processMessage what=2 |
| D/hsm1 ( 1999): mS2.processMessage what=3 |
| D/hsm1 ( 1999): mS2.exit |
| D/hsm1 ( 1999): mP1.exit |
| D/hsm1 ( 1999): mP2.enter |
| D/hsm1 ( 1999): mP2.processMessage what=3 |
| D/hsm1 ( 1999): mP2.processMessage what=4 |
| D/hsm1 ( 1999): mP2.processMessage what=5 |
| D/hsm1 ( 1999): mP2.exit |
| D/hsm1 ( 1999): halting |
| </pre> |
| */ |
| public class StateMachine { |
| // Name of the state machine and used as logging tag |
| private String mName; |
| |
| /** Message.what value when quitting */ |
| private static final int SM_QUIT_CMD = -1; |
| |
| /** Message.what value when initializing */ |
| private static final int SM_INIT_CMD = -2; |
| |
| /** |
| * Convenience constant that maybe returned by processMessage |
| * to indicate the message was processed and is not to be |
| * processed by parent states |
| */ |
| public static final boolean HANDLED = true; |
| |
| /** |
| * Convenience constant that maybe returned by processMessage |
| * to indicate the message was NOT processed and is to be |
| * processed by parent states |
| */ |
| public static final boolean NOT_HANDLED = false; |
| |
| /** |
| * StateMachine logging record. |
| * {@hide} |
| */ |
| public static class LogRec { |
| private StateMachine mSm; |
| private long mTime; |
| private int mWhat; |
| private String mInfo; |
| private IState mState; |
| private IState mOrgState; |
| private IState mDstState; |
| |
| /** |
| * Constructor |
| * |
| * @param msg |
| * @param state the state which handled the message |
| * @param orgState is the first state the received the message but |
| * did not processes the message. |
| * @param transToState is the state that was transitioned to after the message was |
| * processed. |
| */ |
| LogRec(StateMachine sm, Message msg, String info, IState state, IState orgState, |
| IState transToState) { |
| update(sm, msg, info, state, orgState, transToState); |
| } |
| |
| /** |
| * Update the information in the record. |
| * @param state that handled the message |
| * @param orgState is the first state the received the message |
| * @param dstState is the state that was the transition target when logging |
| */ |
| public void update(StateMachine sm, Message msg, String info, IState state, IState orgState, |
| IState dstState) { |
| mSm = sm; |
| mTime = System.currentTimeMillis(); |
| mWhat = (msg != null) ? msg.what : 0; |
| mInfo = info; |
| mState = state; |
| mOrgState = orgState; |
| mDstState = dstState; |
| } |
| |
| /** |
| * @return time stamp |
| */ |
| public long getTime() { |
| return mTime; |
| } |
| |
| /** |
| * @return msg.what |
| */ |
| public long getWhat() { |
| return mWhat; |
| } |
| |
| /** |
| * @return the command that was executing |
| */ |
| public String getInfo() { |
| return mInfo; |
| } |
| |
| /** |
| * @return the state that handled this message |
| */ |
| public IState getState() { |
| return mState; |
| } |
| |
| /** |
| * @return the state destination state if a transition is occurring or null if none. |
| */ |
| public IState getDestState() { |
| return mDstState; |
| } |
| |
| /** |
| * @return the original state that received the message. |
| */ |
| public IState getOriginalState() { |
| return mOrgState; |
| } |
| |
| @Override |
| public String toString() { |
| StringBuilder sb = new StringBuilder(); |
| sb.append("time="); |
| Calendar c = Calendar.getInstance(); |
| c.setTimeInMillis(mTime); |
| sb.append(String.format("%tm-%td %tH:%tM:%tS.%tL", c, c, c, c, c, c)); |
| sb.append(" processed="); |
| sb.append(mState == null ? "<null>" : mState.getName()); |
| sb.append(" org="); |
| sb.append(mOrgState == null ? "<null>" : mOrgState.getName()); |
| sb.append(" dest="); |
| sb.append(mDstState == null ? "<null>" : mDstState.getName()); |
| sb.append(" what="); |
| String what = mSm != null ? mSm.getWhatToString(mWhat) : ""; |
| if (TextUtils.isEmpty(what)) { |
| sb.append(mWhat); |
| sb.append("(0x"); |
| sb.append(Integer.toHexString(mWhat)); |
| sb.append(")"); |
| } else { |
| sb.append(what); |
| } |
| if (!TextUtils.isEmpty(mInfo)) { |
| sb.append(" "); |
| sb.append(mInfo); |
| } |
| return sb.toString(); |
| } |
| } |
| |
| /** |
| * A list of log records including messages recently processed by the state machine. |
| * |
| * The class maintains a list of log records including messages |
| * recently processed. The list is finite and may be set in the |
| * constructor or by calling setSize. The public interface also |
| * includes size which returns the number of recent records, |
| * count which is the number of records processed since the |
| * the last setSize, get which returns a record and |
| * add which adds a record. |
| */ |
| private static class LogRecords { |
| |
| private static final int DEFAULT_SIZE = 20; |
| |
| private Vector<LogRec> mLogRecVector = new Vector<LogRec>(); |
| private int mMaxSize = DEFAULT_SIZE; |
| private int mOldestIndex = 0; |
| private int mCount = 0; |
| private boolean mLogOnlyTransitions = false; |
| |
| /** |
| * private constructor use add |
| */ |
| private LogRecords() { |
| } |
| |
| /** |
| * Set size of messages to maintain and clears all current records. |
| * |
| * @param maxSize number of records to maintain at anyone time. |
| */ |
| synchronized void setSize(int maxSize) { |
| // TODO: once b/28217358 is fixed, add unit tests to verify that these variables are |
| // cleared after calling this method, and that subsequent calls to get() function as |
| // expected. |
| mMaxSize = maxSize; |
| mOldestIndex = 0; |
| mCount = 0; |
| mLogRecVector.clear(); |
| } |
| |
| synchronized void setLogOnlyTransitions(boolean enable) { |
| mLogOnlyTransitions = enable; |
| } |
| |
| synchronized boolean logOnlyTransitions() { |
| return mLogOnlyTransitions; |
| } |
| |
| /** |
| * @return the number of recent records. |
| */ |
| synchronized int size() { |
| return mLogRecVector.size(); |
| } |
| |
| /** |
| * @return the total number of records processed since size was set. |
| */ |
| synchronized int count() { |
| return mCount; |
| } |
| |
| /** |
| * Clear the list of records. |
| */ |
| synchronized void cleanup() { |
| mLogRecVector.clear(); |
| } |
| |
| /** |
| * @return the information on a particular record. 0 is the oldest |
| * record and size()-1 is the newest record. If the index is to |
| * large null is returned. |
| */ |
| synchronized LogRec get(int index) { |
| int nextIndex = mOldestIndex + index; |
| if (nextIndex >= mMaxSize) { |
| nextIndex -= mMaxSize; |
| } |
| if (nextIndex >= size()) { |
| return null; |
| } else { |
| return mLogRecVector.get(nextIndex); |
| } |
| } |
| |
| /** |
| * Add a processed message. |
| * |
| * @param msg |
| * @param messageInfo to be stored |
| * @param state that handled the message |
| * @param orgState is the first state the received the message but |
| * did not processes the message. |
| * @param transToState is the state that was transitioned to after the message was |
| * processed. |
| * |
| */ |
| synchronized void add(StateMachine sm, Message msg, String messageInfo, IState state, |
| IState orgState, IState transToState) { |
| mCount += 1; |
| if (mLogRecVector.size() < mMaxSize) { |
| mLogRecVector.add(new LogRec(sm, msg, messageInfo, state, orgState, transToState)); |
| } else { |
| LogRec pmi = mLogRecVector.get(mOldestIndex); |
| mOldestIndex += 1; |
| if (mOldestIndex >= mMaxSize) { |
| mOldestIndex = 0; |
| } |
| pmi.update(sm, msg, messageInfo, state, orgState, transToState); |
| } |
| } |
| } |
| |
| private static class SmHandler extends Handler { |
| |
| /** true if StateMachine has quit */ |
| private boolean mHasQuit = false; |
| |
| /** The debug flag */ |
| private boolean mDbg = false; |
| |
| /** The SmHandler object, identifies that message is internal */ |
| private static final Object mSmHandlerObj = new Object(); |
| |
| /** The current message */ |
| private Message mMsg; |
| |
| /** A list of log records including messages this state machine has processed */ |
| private LogRecords mLogRecords = new LogRecords(); |
| |
| /** true if construction of the state machine has not been completed */ |
| private boolean mIsConstructionCompleted; |
| |
| /** Stack used to manage the current hierarchy of states */ |
| private StateInfo mStateStack[]; |
| |
| /** Top of mStateStack */ |
| private int mStateStackTopIndex = -1; |
| |
| /** A temporary stack used to manage the state stack */ |
| private StateInfo mTempStateStack[]; |
| |
| /** The top of the mTempStateStack */ |
| private int mTempStateStackCount; |
| |
| /** State used when state machine is halted */ |
| private HaltingState mHaltingState = new HaltingState(); |
| |
| /** State used when state machine is quitting */ |
| private QuittingState mQuittingState = new QuittingState(); |
| |
| /** Reference to the StateMachine */ |
| private StateMachine mSm; |
| |
| /** |
| * Information about a state. |
| * Used to maintain the hierarchy. |
| */ |
| private class StateInfo { |
| /** The state */ |
| State state; |
| |
| /** The parent of this state, null if there is no parent */ |
| StateInfo parentStateInfo; |
| |
| /** True when the state has been entered and on the stack */ |
| boolean active; |
| |
| /** |
| * Convert StateInfo to string |
| */ |
| @Override |
| public String toString() { |
| return "state=" + state.getName() + ",active=" + active + ",parent=" |
| + ((parentStateInfo == null) ? "null" : parentStateInfo.state.getName()); |
| } |
| } |
| |
| /** The map of all of the states in the state machine */ |
| private HashMap<State, StateInfo> mStateInfo = new HashMap<State, StateInfo>(); |
| |
| /** The initial state that will process the first message */ |
| private State mInitialState; |
| |
| /** The destination state when transitionTo has been invoked */ |
| private State mDestState; |
| |
| /** |
| * Indicates if a transition is in progress |
| * |
| * This will be true for all calls of State.exit and all calls of State.enter except for the |
| * last enter call for the current destination state. |
| */ |
| private boolean mTransitionInProgress = false; |
| |
| /** The list of deferred messages */ |
| private ArrayList<Message> mDeferredMessages = new ArrayList<Message>(); |
| |
| /** |
| * State entered when transitionToHaltingState is called. |
| */ |
| private class HaltingState extends State { |
| @Override |
| public boolean processMessage(Message msg) { |
| mSm.haltedProcessMessage(msg); |
| return true; |
| } |
| } |
| |
| /** |
| * State entered when a valid quit message is handled. |
| */ |
| private class QuittingState extends State { |
| @Override |
| public boolean processMessage(Message msg) { |
| return NOT_HANDLED; |
| } |
| } |
| |
| /** |
| * Handle messages sent to the state machine by calling |
| * the current state's processMessage. It also handles |
| * the enter/exit calls and placing any deferred messages |
| * back onto the queue when transitioning to a new state. |
| */ |
| @Override |
| public final void handleMessage(Message msg) { |
| if (!mHasQuit) { |
| if (mSm != null && msg.what != SM_INIT_CMD && msg.what != SM_QUIT_CMD) { |
| mSm.onPreHandleMessage(msg); |
| } |
| |
| if (mDbg) mSm.log("handleMessage: E msg.what=" + msg.what); |
| |
| /** Save the current message */ |
| mMsg = msg; |
| |
| /** State that processed the message */ |
| State msgProcessedState = null; |
| if (mIsConstructionCompleted || (mMsg.what == SM_QUIT_CMD)) { |
| /** Normal path */ |
| msgProcessedState = processMsg(msg); |
| } else if (!mIsConstructionCompleted && (mMsg.what == SM_INIT_CMD) |
| && (mMsg.obj == mSmHandlerObj)) { |
| /** Initial one time path. */ |
| mIsConstructionCompleted = true; |
| invokeEnterMethods(0); |
| } else { |
| throw new RuntimeException("StateMachine.handleMessage: " |
| + "The start method not called, received msg: " + msg); |
| } |
| performTransitions(msgProcessedState, msg); |
| |
| // We need to check if mSm == null here as we could be quitting. |
| if (mDbg && mSm != null) mSm.log("handleMessage: X"); |
| |
| if (mSm != null && msg.what != SM_INIT_CMD && msg.what != SM_QUIT_CMD) { |
| mSm.onPostHandleMessage(msg); |
| } |
| } |
| } |
| |
| /** |
| * Do any transitions |
| * @param msgProcessedState is the state that processed the message |
| */ |
| private void performTransitions(State msgProcessedState, Message msg) { |
| /** |
| * If transitionTo has been called, exit and then enter |
| * the appropriate states. We loop on this to allow |
| * enter and exit methods to use transitionTo. |
| */ |
| State orgState = mStateStack[mStateStackTopIndex].state; |
| |
| /** |
| * Record whether message needs to be logged before we transition and |
| * and we won't log special messages SM_INIT_CMD or SM_QUIT_CMD which |
| * always set msg.obj to the handler. |
| */ |
| boolean recordLogMsg = mSm.recordLogRec(mMsg) && (msg.obj != mSmHandlerObj); |
| |
| if (mLogRecords.logOnlyTransitions()) { |
| /** Record only if there is a transition */ |
| if (mDestState != null) { |
| mLogRecords.add(mSm, mMsg, mSm.getLogRecString(mMsg), msgProcessedState, |
| orgState, mDestState); |
| } |
| } else if (recordLogMsg) { |
| /** Record message */ |
| mLogRecords.add(mSm, mMsg, mSm.getLogRecString(mMsg), msgProcessedState, orgState, |
| mDestState); |
| } |
| |
| State destState = mDestState; |
| if (destState != null) { |
| /** |
| * Process the transitions including transitions in the enter/exit methods |
| */ |
| while (true) { |
| if (mDbg) mSm.log("handleMessage: new destination call exit/enter"); |
| |
| /** |
| * Determine the states to exit and enter and return the |
| * common ancestor state of the enter/exit states. Then |
| * invoke the exit methods then the enter methods. |
| */ |
| StateInfo commonStateInfo = setupTempStateStackWithStatesToEnter(destState); |
| // flag is cleared in invokeEnterMethods before entering the target state |
| mTransitionInProgress = true; |
| invokeExitMethods(commonStateInfo); |
| int stateStackEnteringIndex = moveTempStateStackToStateStack(); |
| invokeEnterMethods(stateStackEnteringIndex); |
| |
| /** |
| * Since we have transitioned to a new state we need to have |
| * any deferred messages moved to the front of the message queue |
| * so they will be processed before any other messages in the |
| * message queue. |
| */ |
| moveDeferredMessageAtFrontOfQueue(); |
| |
| if (destState != mDestState) { |
| // A new mDestState so continue looping |
| destState = mDestState; |
| } else { |
| // No change in mDestState so we're done |
| break; |
| } |
| } |
| mDestState = null; |
| } |
| |
| /** |
| * After processing all transitions check and |
| * see if the last transition was to quit or halt. |
| */ |
| if (destState != null) { |
| if (destState == mQuittingState) { |
| /** |
| * Call onQuitting to let subclasses cleanup. |
| */ |
| mSm.onQuitting(); |
| cleanupAfterQuitting(); |
| } else if (destState == mHaltingState) { |
| /** |
| * Call onHalting() if we've transitioned to the halting |
| * state. All subsequent messages will be processed in |
| * in the halting state which invokes haltedProcessMessage(msg); |
| */ |
| mSm.onHalting(); |
| } |
| } |
| } |
| |
| /** |
| * Cleanup all the static variables and the looper after the SM has been quit. |
| */ |
| private final void cleanupAfterQuitting() { |
| if (mSm.mSmThread != null) { |
| // If we made the thread then quit looper which stops the thread. |
| getLooper().quit(); |
| mSm.mSmThread = null; |
| } |
| |
| mSm.mSmHandler = null; |
| mSm = null; |
| mMsg = null; |
| mLogRecords.cleanup(); |
| mStateStack = null; |
| mTempStateStack = null; |
| mStateInfo.clear(); |
| mInitialState = null; |
| mDestState = null; |
| mDeferredMessages.clear(); |
| mHasQuit = true; |
| } |
| |
| /** |
| * Complete the construction of the state machine. |
| */ |
| private final void completeConstruction() { |
| if (mDbg) mSm.log("completeConstruction: E"); |
| |
| /** |
| * Determine the maximum depth of the state hierarchy |
| * so we can allocate the state stacks. |
| */ |
| int maxDepth = 0; |
| for (StateInfo si : mStateInfo.values()) { |
| int depth = 0; |
| for (StateInfo i = si; i != null; depth++) { |
| i = i.parentStateInfo; |
| } |
| if (maxDepth < depth) { |
| maxDepth = depth; |
| } |
| } |
| if (mDbg) mSm.log("completeConstruction: maxDepth=" + maxDepth); |
| |
| mStateStack = new StateInfo[maxDepth]; |
| mTempStateStack = new StateInfo[maxDepth]; |
| setupInitialStateStack(); |
| |
| /** Sending SM_INIT_CMD message to invoke enter methods asynchronously */ |
| sendMessageAtFrontOfQueue(obtainMessage(SM_INIT_CMD, mSmHandlerObj)); |
| |
| if (mDbg) mSm.log("completeConstruction: X"); |
| } |
| |
| /** |
| * Process the message. If the current state doesn't handle |
| * it, call the states parent and so on. If it is never handled then |
| * call the state machines unhandledMessage method. |
| * @return the state that processed the message |
| */ |
| private final State processMsg(Message msg) { |
| StateInfo curStateInfo = mStateStack[mStateStackTopIndex]; |
| if (mDbg) { |
| mSm.log("processMsg: " + curStateInfo.state.getName()); |
| } |
| |
| if (isQuit(msg)) { |
| transitionTo(mQuittingState); |
| } else { |
| while (!curStateInfo.state.processMessage(msg)) { |
| /** |
| * Not processed |
| */ |
| curStateInfo = curStateInfo.parentStateInfo; |
| if (curStateInfo == null) { |
| /** |
| * No parents left so it's not handled |
| */ |
| mSm.unhandledMessage(msg); |
| break; |
| } |
| if (mDbg) { |
| mSm.log("processMsg: " + curStateInfo.state.getName()); |
| } |
| } |
| } |
| return (curStateInfo != null) ? curStateInfo.state : null; |
| } |
| |
| /** |
| * Call the exit method for each state from the top of stack |
| * up to the common ancestor state. |
| */ |
| private final void invokeExitMethods(StateInfo commonStateInfo) { |
| while ((mStateStackTopIndex >= 0) |
| && (mStateStack[mStateStackTopIndex] != commonStateInfo)) { |
| State curState = mStateStack[mStateStackTopIndex].state; |
| if (mDbg) mSm.log("invokeExitMethods: " + curState.getName()); |
| curState.exit(); |
| mStateStack[mStateStackTopIndex].active = false; |
| mStateStackTopIndex -= 1; |
| } |
| } |
| |
| /** |
| * Invoke the enter method starting at the entering index to top of state stack |
| */ |
| private final void invokeEnterMethods(int stateStackEnteringIndex) { |
| for (int i = stateStackEnteringIndex; i <= mStateStackTopIndex; i++) { |
| if (stateStackEnteringIndex == mStateStackTopIndex) { |
| // Last enter state for transition |
| mTransitionInProgress = false; |
| } |
| if (mDbg) mSm.log("invokeEnterMethods: " + mStateStack[i].state.getName()); |
| mStateStack[i].state.enter(); |
| mStateStack[i].active = true; |
| } |
| mTransitionInProgress = false; // ensure flag set to false if no methods called |
| } |
| |
| /** |
| * Move the deferred message to the front of the message queue. |
| */ |
| private final void moveDeferredMessageAtFrontOfQueue() { |
| /** |
| * The oldest messages on the deferred list must be at |
| * the front of the queue so start at the back, which |
| * as the most resent message and end with the oldest |
| * messages at the front of the queue. |
| */ |
| for (int i = mDeferredMessages.size() - 1; i >= 0; i--) { |
| Message curMsg = mDeferredMessages.get(i); |
| if (mDbg) mSm.log("moveDeferredMessageAtFrontOfQueue; what=" + curMsg.what); |
| sendMessageAtFrontOfQueue(curMsg); |
| } |
| mDeferredMessages.clear(); |
| } |
| |
| /** |
| * Move the contents of the temporary stack to the state stack |
| * reversing the order of the items on the temporary stack as |
| * they are moved. |
| * |
| * @return index into mStateStack where entering needs to start |
| */ |
| private final int moveTempStateStackToStateStack() { |
| int startingIndex = mStateStackTopIndex + 1; |
| int i = mTempStateStackCount - 1; |
| int j = startingIndex; |
| while (i >= 0) { |
| if (mDbg) mSm.log("moveTempStackToStateStack: i=" + i + ",j=" + j); |
| mStateStack[j] = mTempStateStack[i]; |
| j += 1; |
| i -= 1; |
| } |
| |
| mStateStackTopIndex = j - 1; |
| if (mDbg) { |
| mSm.log("moveTempStackToStateStack: X mStateStackTop=" + mStateStackTopIndex |
| + ",startingIndex=" + startingIndex + ",Top=" |
| + mStateStack[mStateStackTopIndex].state.getName()); |
| } |
| return startingIndex; |
| } |
| |
| /** |
| * Setup the mTempStateStack with the states we are going to enter. |
| * |
| * This is found by searching up the destState's ancestors for a |
| * state that is already active i.e. StateInfo.active == true. |
| * The destStae and all of its inactive parents will be on the |
| * TempStateStack as the list of states to enter. |
| * |
| * @return StateInfo of the common ancestor for the destState and |
| * current state or null if there is no common parent. |
| */ |
| private final StateInfo setupTempStateStackWithStatesToEnter(State destState) { |
| /** |
| * Search up the parent list of the destination state for an active |
| * state. Use a do while() loop as the destState must always be entered |
| * even if it is active. This can happen if we are exiting/entering |
| * the current state. |
| */ |
| mTempStateStackCount = 0; |
| StateInfo curStateInfo = mStateInfo.get(destState); |
| do { |
| mTempStateStack[mTempStateStackCount++] = curStateInfo; |
| curStateInfo = curStateInfo.parentStateInfo; |
| } while ((curStateInfo != null) && !curStateInfo.active); |
| |
| if (mDbg) { |
| mSm.log("setupTempStateStackWithStatesToEnter: X mTempStateStackCount=" |
| + mTempStateStackCount + ",curStateInfo: " + curStateInfo); |
| } |
| return curStateInfo; |
| } |
| |
| /** |
| * Initialize StateStack to mInitialState. |
| */ |
| private final void setupInitialStateStack() { |
| if (mDbg) { |
| mSm.log("setupInitialStateStack: E mInitialState=" + mInitialState.getName()); |
| } |
| |
| StateInfo curStateInfo = mStateInfo.get(mInitialState); |
| for (mTempStateStackCount = 0; curStateInfo != null; mTempStateStackCount++) { |
| mTempStateStack[mTempStateStackCount] = curStateInfo; |
| curStateInfo = curStateInfo.parentStateInfo; |
| } |
| |
| // Empty the StateStack |
| mStateStackTopIndex = -1; |
| |
| moveTempStateStackToStateStack(); |
| } |
| |
| /** |
| * @return current message |
| */ |
| private final Message getCurrentMessage() { |
| return mMsg; |
| } |
| |
| /** |
| * @return current state |
| */ |
| private final IState getCurrentState() { |
| return mStateStack[mStateStackTopIndex].state; |
| } |
| |
| /** |
| * Add a new state to the state machine. Bottom up addition |
| * of states is allowed but the same state may only exist |
| * in one hierarchy. |
| * |
| * @param state the state to add |
| * @param parent the parent of state |
| * @return stateInfo for this state |
| */ |
| private final StateInfo addState(State state, State parent) { |
| if (mDbg) { |
| mSm.log("addStateInternal: E state=" + state.getName() + ",parent=" |
| + ((parent == null) ? "" : parent.getName())); |
| } |
| StateInfo parentStateInfo = null; |
| if (parent != null) { |
| parentStateInfo = mStateInfo.get(parent); |
| if (parentStateInfo == null) { |
| // Recursively add our parent as it's not been added yet. |
| parentStateInfo = addState(parent, null); |
| } |
| } |
| StateInfo stateInfo = mStateInfo.get(state); |
| if (stateInfo == null) { |
| stateInfo = new StateInfo(); |
| mStateInfo.put(state, stateInfo); |
| } |
| |
| // Validate that we aren't adding the same state in two different hierarchies. |
| if ((stateInfo.parentStateInfo != null) |
| && (stateInfo.parentStateInfo != parentStateInfo)) { |
| throw new RuntimeException("state already added"); |
| } |
| stateInfo.state = state; |
| stateInfo.parentStateInfo = parentStateInfo; |
| stateInfo.active = false; |
| if (mDbg) mSm.log("addStateInternal: X stateInfo: " + stateInfo); |
| return stateInfo; |
| } |
| |
| /** |
| * Remove a state from the state machine. Will not remove the state if it is currently |
| * active or if it has any children in the hierarchy. |
| * @param state the state to remove |
| */ |
| private void removeState(State state) { |
| StateInfo stateInfo = mStateInfo.get(state); |
| if (stateInfo == null || stateInfo.active) { |
| return; |
| } |
| boolean isParent = mStateInfo.values().stream() |
| .filter(si -> si.parentStateInfo == stateInfo) |
| .findAny() |
| .isPresent(); |
| if (isParent) { |
| return; |
| } |
| mStateInfo.remove(state); |
| } |
| |
| /** |
| * Constructor |
| * |
| * @param looper for dispatching messages |
| * @param sm the hierarchical state machine |
| */ |
| private SmHandler(Looper looper, StateMachine sm) { |
| super(looper); |
| mSm = sm; |
| |
| addState(mHaltingState, null); |
| addState(mQuittingState, null); |
| } |
| |
| /** @see StateMachine#setInitialState(State) */ |
| private final void setInitialState(State initialState) { |
| if (mDbg) mSm.log("setInitialState: initialState=" + initialState.getName()); |
| mInitialState = initialState; |
| } |
| |
| /** @see StateMachine#transitionTo(IState) */ |
| private final void transitionTo(IState destState) { |
| if (mTransitionInProgress) { |
| Log.wtf(mSm.mName, "transitionTo called while transition already in progress to " + |
| mDestState + ", new target state=" + destState); |
| } |
| mDestState = (State) destState; |
| if (mDbg) mSm.log("transitionTo: destState=" + mDestState.getName()); |
| } |
| |
| /** @see StateMachine#deferMessage(Message) */ |
| private final void deferMessage(Message msg) { |
| if (mDbg) mSm.log("deferMessage: msg=" + msg.what); |
| |
| /* Copy the "msg" to "newMsg" as "msg" will be recycled */ |
| Message newMsg = obtainMessage(); |
| newMsg.copyFrom(msg); |
| |
| mDeferredMessages.add(newMsg); |
| } |
| |
| /** @see StateMachine#quit() */ |
| private final void quit() { |
| if (mDbg) mSm.log("quit:"); |
| sendMessage(obtainMessage(SM_QUIT_CMD, mSmHandlerObj)); |
| } |
| |
| /** @see StateMachine#quitNow() */ |
| private final void quitNow() { |
| if (mDbg) mSm.log("quitNow:"); |
| sendMessageAtFrontOfQueue(obtainMessage(SM_QUIT_CMD, mSmHandlerObj)); |
| } |
| |
| /** Validate that the message was sent by quit or quitNow. */ |
| private final boolean isQuit(Message msg) { |
| return (msg.what == SM_QUIT_CMD) && (msg.obj == mSmHandlerObj); |
| } |
| |
| /** @see StateMachine#isDbg() */ |
| private final boolean isDbg() { |
| return mDbg; |
| } |
| |
| /** @see StateMachine#setDbg(boolean) */ |
| private final void setDbg(boolean dbg) { |
| mDbg = dbg; |
| } |
| |
| } |
| |
| private SmHandler mSmHandler; |
| private HandlerThread mSmThread; |
| |
| /** |
| * Initialize. |
| * |
| * @param looper for this state machine |
| * @param name of the state machine |
| */ |
| private void initStateMachine(String name, Looper looper) { |
| mName = name; |
| mSmHandler = new SmHandler(looper, this); |
| } |
| |
| /** |
| * Constructor creates a StateMachine with its own thread. |
| * |
| * @param name of the state machine |
| */ |
| @UnsupportedAppUsage |
| protected StateMachine(String name) { |
| mSmThread = new HandlerThread(name); |
| mSmThread.start(); |
| Looper looper = mSmThread.getLooper(); |
| |
| initStateMachine(name, looper); |
| } |
| |
| /** |
| * Constructor creates a StateMachine using the looper. |
| * |
| * @param name of the state machine |
| */ |
| @UnsupportedAppUsage |
| protected StateMachine(String name, Looper looper) { |
| initStateMachine(name, looper); |
| } |
| |
| /** |
| * Constructor creates a StateMachine using the handler. |
| * |
| * @param name of the state machine |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| protected StateMachine(String name, Handler handler) { |
| initStateMachine(name, handler.getLooper()); |
| } |
| |
| /** |
| * Notifies subclass that the StateMachine handler is about to process the Message msg |
| * @param msg The message that is being handled |
| */ |
| protected void onPreHandleMessage(Message msg) { |
| } |
| |
| /** |
| * Notifies subclass that the StateMachine handler has finished processing the Message msg and |
| * has possibly transitioned to a new state. |
| * @param msg The message that is being handled |
| */ |
| protected void onPostHandleMessage(Message msg) { |
| } |
| |
| /** |
| * Add a new state to the state machine |
| * @param state the state to add |
| * @param parent the parent of state |
| */ |
| public final void addState(State state, State parent) { |
| mSmHandler.addState(state, parent); |
| } |
| |
| /** |
| * Add a new state to the state machine, parent will be null |
| * @param state to add |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public final void addState(State state) { |
| mSmHandler.addState(state, null); |
| } |
| |
| /** |
| * Removes a state from the state machine, unless it is currently active or if it has children. |
| * @param state state to remove |
| */ |
| public final void removeState(State state) { |
| mSmHandler.removeState(state); |
| } |
| |
| /** |
| * Set the initial state. This must be invoked before |
| * and messages are sent to the state machine. |
| * |
| * @param initialState is the state which will receive the first message. |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public final void setInitialState(State initialState) { |
| mSmHandler.setInitialState(initialState); |
| } |
| |
| /** |
| * @return current message |
| */ |
| public final Message getCurrentMessage() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return null; |
| return smh.getCurrentMessage(); |
| } |
| |
| /** |
| * @return current state |
| */ |
| public final IState getCurrentState() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return null; |
| return smh.getCurrentState(); |
| } |
| |
| /** |
| * transition to destination state. Upon returning |
| * from processMessage the current state's exit will |
| * be executed and upon the next message arriving |
| * destState.enter will be invoked. |
| * |
| * this function can also be called inside the enter function of the |
| * previous transition target, but the behavior is undefined when it is |
| * called mid-way through a previous transition (for example, calling this |
| * in the enter() routine of a intermediate node when the current transition |
| * target is one of the nodes descendants). |
| * |
| * @param destState will be the state that receives the next message. |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public final void transitionTo(IState destState) { |
| mSmHandler.transitionTo(destState); |
| } |
| |
| /** |
| * transition to halt state. Upon returning |
| * from processMessage we will exit all current |
| * states, execute the onHalting() method and then |
| * for all subsequent messages haltedProcessMessage |
| * will be called. |
| */ |
| public final void transitionToHaltingState() { |
| mSmHandler.transitionTo(mSmHandler.mHaltingState); |
| } |
| |
| /** |
| * Defer this message until next state transition. |
| * Upon transitioning all deferred messages will be |
| * placed on the queue and reprocessed in the original |
| * order. (i.e. The next state the oldest messages will |
| * be processed first) |
| * |
| * @param msg is deferred until the next transition. |
| */ |
| public final void deferMessage(Message msg) { |
| mSmHandler.deferMessage(msg); |
| } |
| |
| /** |
| * Called when message wasn't handled |
| * |
| * @param msg that couldn't be handled. |
| */ |
| protected void unhandledMessage(Message msg) { |
| if (mSmHandler.mDbg) loge(" - unhandledMessage: msg.what=" + msg.what); |
| } |
| |
| /** |
| * Called for any message that is received after |
| * transitionToHalting is called. |
| */ |
| protected void haltedProcessMessage(Message msg) { |
| } |
| |
| /** |
| * This will be called once after handling a message that called |
| * transitionToHalting. All subsequent messages will invoke |
| * {@link StateMachine#haltedProcessMessage(Message)} |
| */ |
| protected void onHalting() { |
| } |
| |
| /** |
| * This will be called once after a quit message that was NOT handled by |
| * the derived StateMachine. The StateMachine will stop and any subsequent messages will be |
| * ignored. In addition, if this StateMachine created the thread, the thread will |
| * be stopped after this method returns. |
| */ |
| protected void onQuitting() { |
| } |
| |
| /** |
| * @return the name |
| */ |
| public final String getName() { |
| return mName; |
| } |
| |
| /** |
| * Set number of log records to maintain and clears all current records. |
| * |
| * @param maxSize number of messages to maintain at anyone time. |
| */ |
| public final void setLogRecSize(int maxSize) { |
| mSmHandler.mLogRecords.setSize(maxSize); |
| } |
| |
| /** |
| * Set to log only messages that cause a state transition |
| * |
| * @param enable {@code true} to enable, {@code false} to disable |
| */ |
| public final void setLogOnlyTransitions(boolean enable) { |
| mSmHandler.mLogRecords.setLogOnlyTransitions(enable); |
| } |
| |
| /** |
| * @return the number of log records currently readable |
| */ |
| public final int getLogRecSize() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return 0; |
| return smh.mLogRecords.size(); |
| } |
| |
| /** |
| * @return the number of log records we can store |
| */ |
| @VisibleForTesting |
| public final int getLogRecMaxSize() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return 0; |
| return smh.mLogRecords.mMaxSize; |
| } |
| |
| /** |
| * @return the total number of records processed |
| */ |
| public final int getLogRecCount() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return 0; |
| return smh.mLogRecords.count(); |
| } |
| |
| /** |
| * @return a log record, or null if index is out of range |
| */ |
| public final LogRec getLogRec(int index) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return null; |
| return smh.mLogRecords.get(index); |
| } |
| |
| /** |
| * @return a copy of LogRecs as a collection |
| */ |
| public final Collection<LogRec> copyLogRecs() { |
| Vector<LogRec> vlr = new Vector<LogRec>(); |
| SmHandler smh = mSmHandler; |
| if (smh != null) { |
| for (LogRec lr : smh.mLogRecords.mLogRecVector) { |
| vlr.add(lr); |
| } |
| } |
| return vlr; |
| } |
| |
| /** |
| * Add the string to LogRecords. |
| * |
| * @param string |
| */ |
| public void addLogRec(String string) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| smh.mLogRecords.add(this, smh.getCurrentMessage(), string, smh.getCurrentState(), |
| smh.mStateStack[smh.mStateStackTopIndex].state, smh.mDestState); |
| } |
| |
| /** |
| * @return true if msg should be saved in the log, default is true. |
| */ |
| protected boolean recordLogRec(Message msg) { |
| return true; |
| } |
| |
| /** |
| * Return a string to be logged by LogRec, default |
| * is an empty string. Override if additional information is desired. |
| * |
| * @param msg that was processed |
| * @return information to be logged as a String |
| */ |
| protected String getLogRecString(Message msg) { |
| return ""; |
| } |
| |
| /** |
| * @return the string for msg.what |
| */ |
| protected String getWhatToString(int what) { |
| return null; |
| } |
| |
| /** |
| * @return Handler, maybe null if state machine has quit. |
| */ |
| public final Handler getHandler() { |
| return mSmHandler; |
| } |
| |
| /** |
| * Get a message and set Message.target state machine handler. |
| * |
| * Note: The handler can be null if the state machine has quit, |
| * which means target will be null and may cause a AndroidRuntimeException |
| * in MessageQueue#enqueMessage if sent directly or if sent using |
| * StateMachine#sendMessage the message will just be ignored. |
| * |
| * @return A Message object from the global pool |
| */ |
| public final Message obtainMessage() { |
| return Message.obtain(mSmHandler); |
| } |
| |
| /** |
| * Get a message and set Message.target state machine handler, what. |
| * |
| * Note: The handler can be null if the state machine has quit, |
| * which means target will be null and may cause a AndroidRuntimeException |
| * in MessageQueue#enqueMessage if sent directly or if sent using |
| * StateMachine#sendMessage the message will just be ignored. |
| * |
| * @param what is the assigned to Message.what. |
| * @return A Message object from the global pool |
| */ |
| public final Message obtainMessage(int what) { |
| return Message.obtain(mSmHandler, what); |
| } |
| |
| /** |
| * Get a message and set Message.target state machine handler, |
| * what and obj. |
| * |
| * Note: The handler can be null if the state machine has quit, |
| * which means target will be null and may cause a AndroidRuntimeException |
| * in MessageQueue#enqueMessage if sent directly or if sent using |
| * StateMachine#sendMessage the message will just be ignored. |
| * |
| * @param what is the assigned to Message.what. |
| * @param obj is assigned to Message.obj. |
| * @return A Message object from the global pool |
| */ |
| public final Message obtainMessage(int what, Object obj) { |
| return Message.obtain(mSmHandler, what, obj); |
| } |
| |
| /** |
| * Get a message and set Message.target state machine handler, |
| * what, arg1 and arg2 |
| * |
| * Note: The handler can be null if the state machine has quit, |
| * which means target will be null and may cause a AndroidRuntimeException |
| * in MessageQueue#enqueMessage if sent directly or if sent using |
| * StateMachine#sendMessage the message will just be ignored. |
| * |
| * @param what is assigned to Message.what |
| * @param arg1 is assigned to Message.arg1 |
| * @return A Message object from the global pool |
| */ |
| public final Message obtainMessage(int what, int arg1) { |
| // use this obtain so we don't match the obtain(h, what, Object) method |
| return Message.obtain(mSmHandler, what, arg1, 0); |
| } |
| |
| /** |
| * Get a message and set Message.target state machine handler, |
| * what, arg1 and arg2 |
| * |
| * Note: The handler can be null if the state machine has quit, |
| * which means target will be null and may cause a AndroidRuntimeException |
| * in MessageQueue#enqueMessage if sent directly or if sent using |
| * StateMachine#sendMessage the message will just be ignored. |
| * |
| * @param what is assigned to Message.what |
| * @param arg1 is assigned to Message.arg1 |
| * @param arg2 is assigned to Message.arg2 |
| * @return A Message object from the global pool |
| */ |
| @UnsupportedAppUsage |
| public final Message obtainMessage(int what, int arg1, int arg2) { |
| return Message.obtain(mSmHandler, what, arg1, arg2); |
| } |
| |
| /** |
| * Get a message and set Message.target state machine handler, |
| * what, arg1, arg2 and obj |
| * |
| * Note: The handler can be null if the state machine has quit, |
| * which means target will be null and may cause a AndroidRuntimeException |
| * in MessageQueue#enqueMessage if sent directly or if sent using |
| * StateMachine#sendMessage the message will just be ignored. |
| * |
| * @param what is assigned to Message.what |
| * @param arg1 is assigned to Message.arg1 |
| * @param arg2 is assigned to Message.arg2 |
| * @param obj is assigned to Message.obj |
| * @return A Message object from the global pool |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public final Message obtainMessage(int what, int arg1, int arg2, Object obj) { |
| return Message.obtain(mSmHandler, what, arg1, arg2, obj); |
| } |
| |
| /** |
| * Enqueue a message to this state machine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| @UnsupportedAppUsage |
| public void sendMessage(int what) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessage(obtainMessage(what)); |
| } |
| |
| /** |
| * Enqueue a message to this state machine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| @UnsupportedAppUsage |
| public void sendMessage(int what, Object obj) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessage(obtainMessage(what, obj)); |
| } |
| |
| /** |
| * Enqueue a message to this state machine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public void sendMessage(int what, int arg1) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessage(obtainMessage(what, arg1)); |
| } |
| |
| /** |
| * Enqueue a message to this state machine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessage(int what, int arg1, int arg2) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessage(obtainMessage(what, arg1, arg2)); |
| } |
| |
| /** |
| * Enqueue a message to this state machine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public void sendMessage(int what, int arg1, int arg2, Object obj) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessage(obtainMessage(what, arg1, arg2, obj)); |
| } |
| |
| /** |
| * Enqueue a message to this state machine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| @UnsupportedAppUsage |
| public void sendMessage(Message msg) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessage(msg); |
| } |
| |
| /** |
| * Enqueue a message to this state machine after a delay. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessageDelayed(int what, long delayMillis) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageDelayed(obtainMessage(what), delayMillis); |
| } |
| |
| /** |
| * Enqueue a message to this state machine after a delay. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessageDelayed(int what, Object obj, long delayMillis) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageDelayed(obtainMessage(what, obj), delayMillis); |
| } |
| |
| /** |
| * Enqueue a message to this state machine after a delay. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessageDelayed(int what, int arg1, long delayMillis) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageDelayed(obtainMessage(what, arg1), delayMillis); |
| } |
| |
| /** |
| * Enqueue a message to this state machine after a delay. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessageDelayed(int what, int arg1, int arg2, long delayMillis) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageDelayed(obtainMessage(what, arg1, arg2), delayMillis); |
| } |
| |
| /** |
| * Enqueue a message to this state machine after a delay. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessageDelayed(int what, int arg1, int arg2, Object obj, |
| long delayMillis) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageDelayed(obtainMessage(what, arg1, arg2, obj), delayMillis); |
| } |
| |
| /** |
| * Enqueue a message to this state machine after a delay. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| public void sendMessageDelayed(Message msg, long delayMillis) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageDelayed(msg, delayMillis); |
| } |
| |
| /** |
| * Enqueue a message to the front of the queue for this state machine. |
| * Protected, may only be called by instances of StateMachine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| protected final void sendMessageAtFrontOfQueue(int what) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageAtFrontOfQueue(obtainMessage(what)); |
| } |
| |
| /** |
| * Enqueue a message to the front of the queue for this state machine. |
| * Protected, may only be called by instances of StateMachine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| protected final void sendMessageAtFrontOfQueue(int what, Object obj) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageAtFrontOfQueue(obtainMessage(what, obj)); |
| } |
| |
| /** |
| * Enqueue a message to the front of the queue for this state machine. |
| * Protected, may only be called by instances of StateMachine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| protected final void sendMessageAtFrontOfQueue(int what, int arg1) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageAtFrontOfQueue(obtainMessage(what, arg1)); |
| } |
| |
| |
| /** |
| * Enqueue a message to the front of the queue for this state machine. |
| * Protected, may only be called by instances of StateMachine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| protected final void sendMessageAtFrontOfQueue(int what, int arg1, int arg2) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageAtFrontOfQueue(obtainMessage(what, arg1, arg2)); |
| } |
| |
| /** |
| * Enqueue a message to the front of the queue for this state machine. |
| * Protected, may only be called by instances of StateMachine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| protected final void sendMessageAtFrontOfQueue(int what, int arg1, int arg2, Object obj) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageAtFrontOfQueue(obtainMessage(what, arg1, arg2, obj)); |
| } |
| |
| /** |
| * Enqueue a message to the front of the queue for this state machine. |
| * Protected, may only be called by instances of StateMachine. |
| * |
| * Message is ignored if state machine has quit. |
| */ |
| protected final void sendMessageAtFrontOfQueue(Message msg) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.sendMessageAtFrontOfQueue(msg); |
| } |
| |
| /** |
| * Removes a message from the message queue. |
| * Protected, may only be called by instances of StateMachine. |
| */ |
| protected final void removeMessages(int what) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.removeMessages(what); |
| } |
| |
| /** |
| * Removes a message from the deferred messages queue. |
| */ |
| protected final void removeDeferredMessages(int what) { |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| Iterator<Message> iterator = smh.mDeferredMessages.iterator(); |
| while (iterator.hasNext()) { |
| Message msg = iterator.next(); |
| if (msg.what == what) iterator.remove(); |
| } |
| } |
| |
| /** |
| * Check if there are any pending messages with code 'what' in deferred messages queue. |
| */ |
| protected final boolean hasDeferredMessages(int what) { |
| SmHandler smh = mSmHandler; |
| if (smh == null) return false; |
| |
| Iterator<Message> iterator = smh.mDeferredMessages.iterator(); |
| while (iterator.hasNext()) { |
| Message msg = iterator.next(); |
| if (msg.what == what) return true; |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Check if there are any pending posts of messages with code 'what' in |
| * the message queue. This does NOT check messages in deferred message queue. |
| */ |
| protected final boolean hasMessages(int what) { |
| SmHandler smh = mSmHandler; |
| if (smh == null) return false; |
| |
| return smh.hasMessages(what); |
| } |
| |
| /** |
| * Validate that the message was sent by |
| * {@link StateMachine#quit} or {@link StateMachine#quitNow}. |
| */ |
| protected final boolean isQuit(Message msg) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return msg.what == SM_QUIT_CMD; |
| |
| return smh.isQuit(msg); |
| } |
| |
| /** |
| * Quit the state machine after all currently queued up messages are processed. |
| */ |
| public final void quit() { |
| // mSmHandler can be null if the state machine is already stopped. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.quit(); |
| } |
| |
| /** |
| * Quit the state machine immediately all currently queued messages will be discarded. |
| */ |
| public final void quitNow() { |
| // mSmHandler can be null if the state machine is already stopped. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.quitNow(); |
| } |
| |
| /** |
| * @return if debugging is enabled |
| */ |
| public boolean isDbg() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return false; |
| |
| return smh.isDbg(); |
| } |
| |
| /** |
| * Set debug enable/disabled. |
| * |
| * @param dbg is true to enable debugging. |
| */ |
| public void setDbg(boolean dbg) { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| smh.setDbg(dbg); |
| } |
| |
| /** |
| * Start the state machine. |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public void start() { |
| // mSmHandler can be null if the state machine has quit. |
| SmHandler smh = mSmHandler; |
| if (smh == null) return; |
| |
| /** Send the complete construction message */ |
| smh.completeConstruction(); |
| } |
| |
| /** |
| * Dump the current state. |
| * |
| * @param fd |
| * @param pw |
| * @param args |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| public void dump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| pw.println(getName() + ":"); |
| pw.println(" total records=" + getLogRecCount()); |
| for (int i = 0; i < getLogRecSize(); i++) { |
| pw.println(" rec[" + i + "]: " + getLogRec(i)); |
| pw.flush(); |
| } |
| final IState curState = getCurrentState(); |
| pw.println("curState=" + (curState == null ? "<QUIT>" : curState.getName())); |
| } |
| |
| @Override |
| public String toString() { |
| String name = "(null)"; |
| String state = "(null)"; |
| try { |
| name = mName.toString(); |
| state = mSmHandler.getCurrentState().getName().toString(); |
| } catch (NullPointerException | ArrayIndexOutOfBoundsException e) { |
| // Will use default(s) initialized above. |
| } |
| return "name=" + name + " state=" + state; |
| } |
| |
| /** |
| * Log with debug and add to the LogRecords. |
| * |
| * @param s is string log |
| */ |
| protected void logAndAddLogRec(String s) { |
| addLogRec(s); |
| log(s); |
| } |
| |
| /** |
| * Log with debug |
| * |
| * @param s is string log |
| */ |
| protected void log(String s) { |
| Log.d(mName, s); |
| } |
| |
| /** |
| * Log with debug attribute |
| * |
| * @param s is string log |
| */ |
| protected void logd(String s) { |
| Log.d(mName, s); |
| } |
| |
| /** |
| * Log with verbose attribute |
| * |
| * @param s is string log |
| */ |
| protected void logv(String s) { |
| Log.v(mName, s); |
| } |
| |
| /** |
| * Log with info attribute |
| * |
| * @param s is string log |
| */ |
| protected void logi(String s) { |
| Log.i(mName, s); |
| } |
| |
| /** |
| * Log with warning attribute |
| * |
| * @param s is string log |
| */ |
| protected void logw(String s) { |
| Log.w(mName, s); |
| } |
| |
| /** |
| * Log with error attribute |
| * |
| * @param s is string log |
| */ |
| protected void loge(String s) { |
| Log.e(mName, s); |
| } |
| |
| /** |
| * Log with error attribute |
| * |
| * @param s is string log |
| * @param e is a Throwable which logs additional information. |
| */ |
| protected void loge(String s, Throwable e) { |
| Log.e(mName, s, e); |
| } |
| } |
