api/src/main/java/io/grpc/CallOptions.java - platform/external/grpc-grpc-java - Git at Google

 /*
  * Copyright 2015 The gRPC Authors
  *
  * 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 io.grpc;

 import static com.google.common.base.Preconditions.checkArgument;

 import com.google.common.base.MoreObjects;
 import com.google.common.base.Preconditions;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
 import javax.annotation.CheckReturnValue;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;

 /**
  * The collection of runtime options for a new RPC call.
  *
  * <p>A field that is not set is {@code null}.
  */
 @Immutable
 @CheckReturnValue
 public final class CallOptions {
   /**
    * A blank {@code CallOptions} that all fields are not set.
    */
   public static final CallOptions DEFAULT;

   static {
     Builder b = new Builder();
     b.customOptions = new Object[0][2];
     b.streamTracerFactories = Collections.emptyList();
     DEFAULT = b.build();
   }

   @Nullable
   private final Deadline deadline;

   @Nullable
   private final Executor executor;

   @Nullable
   private final String authority;

   @Nullable
   private final CallCredentials credentials;

   @Nullable
   private final String compressorName;

   private final Object[][] customOptions;

   private final List<ClientStreamTracer.Factory> streamTracerFactories;

   /**
    * Opposite to fail fast.
    */
   @Nullable
   private final Boolean waitForReady;

   @Nullable
   private final Integer maxInboundMessageSize;
   @Nullable
   private final Integer maxOutboundMessageSize;

   private CallOptions(Builder builder) {
     this.deadline = builder.deadline;
     this.executor = builder.executor;
     this.authority = builder.authority;
     this.credentials = builder.credentials;
     this.compressorName = builder.compressorName;
     this.customOptions = builder.customOptions;
     this.streamTracerFactories = builder.streamTracerFactories;
     this.waitForReady = builder.waitForReady;
     this.maxInboundMessageSize = builder.maxInboundMessageSize;
     this.maxOutboundMessageSize = builder.maxOutboundMessageSize;
   }

   static class Builder {
     Deadline deadline;
     Executor executor;
     String authority;
     CallCredentials credentials;
     String compressorName;
     Object[][] customOptions;
     // Unmodifiable list
     List<ClientStreamTracer.Factory> streamTracerFactories;
     Boolean waitForReady;
     Integer maxInboundMessageSize;
     Integer maxOutboundMessageSize;

     private CallOptions build() {
       return new CallOptions(this);
     }
   }

   /**
    * Override the HTTP/2 authority the channel claims to be connecting to. <em>This is not
    * generally safe.</em> Overriding allows advanced users to re-use a single Channel for multiple
    * services, even if those services are hosted on different domain names. That assumes the
    * server is virtually hosting multiple domains and is guaranteed to continue doing so. It is
    * rare for a service provider to make such a guarantee. <em>At this time, there is no security
    * verification of the overridden value, such as making sure the authority matches the server's
    * TLS certificate.</em>
    */
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1767")
   public CallOptions withAuthority(@Nullable String authority) {
     Builder builder = toBuilder(this);
     builder.authority = authority;
     return builder.build();
   }

   /**
    * Returns a new {@code CallOptions} with the given call credentials.
    */
   public CallOptions withCallCredentials(@Nullable CallCredentials credentials) {
     Builder builder = toBuilder(this);
     builder.credentials = credentials;
     return builder.build();
   }

   /**
    * Sets the compression to use for the call.  The compressor must be a valid name known in the
    * {@link CompressorRegistry}.  By default, the "gzip" compressor will be available.
    *
    * <p>It is only safe to call this if the server supports the compression format chosen. There is
    * no negotiation performed; if the server does not support the compression chosen, the call will
    * fail.
    */
   public CallOptions withCompression(@Nullable String compressorName) {
     Builder builder = toBuilder(this);
     builder.compressorName = compressorName;
     return builder.build();
   }

   /**
    * Returns a new {@code CallOptions} with the given absolute deadline.
    *
    * <p>This is mostly used for propagating an existing deadline. {@link #withDeadlineAfter} is the
    * recommended way of setting a new deadline,
    *
    * @param deadline the deadline or {@code null} for unsetting the deadline.
    */
   public CallOptions withDeadline(@Nullable Deadline deadline) {
     Builder builder = toBuilder(this);
     builder.deadline = deadline;
     return builder.build();
   }

   /**
    * Returns a new {@code CallOptions} with a deadline that is after the given {@code duration} from
    * now.
    */
   public CallOptions withDeadlineAfter(long duration, TimeUnit unit) {
     return withDeadline(Deadline.after(duration, unit));
   }

   /**
    * Returns the deadline or {@code null} if the deadline is not set.
    */
   @Nullable
   public Deadline getDeadline() {
     return deadline;
   }

   /**
    * Enables <a href="https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md">
    * 'wait for ready'</a> for the call. Wait-for-ready queues the RPC until a connection is
    * available. This may dramatically increase the latency of the RPC, but avoids failing
    * "unnecessarily." The default queues the RPC until an attempt to connect has completed, but
    * fails RPCs without sending them if unable to connect.
    */
   public CallOptions withWaitForReady() {
     Builder builder = toBuilder(this);
     builder.waitForReady = Boolean.TRUE;
     return builder.build();
   }

   /**
    * Disables 'wait for ready' feature for the call.
    * This method should be rarely used because the default is without 'wait for ready'.
    */
   public CallOptions withoutWaitForReady() {
     Builder builder = toBuilder(this);
     builder.waitForReady = Boolean.FALSE;
     return builder.build();
   }

   /**
    * Returns the compressor's name.
    */
   @Nullable
   public String getCompressor() {
     return compressorName;
   }

   /**
    * Override the HTTP/2 authority the channel claims to be connecting to. <em>This is not
    * generally safe.</em> Overriding allows advanced users to re-use a single Channel for multiple
    * services, even if those services are hosted on different domain names. That assumes the
    * server is virtually hosting multiple domains and is guaranteed to continue doing so. It is
    * rare for a service provider to make such a guarantee. <em>At this time, there is no security
    * verification of the overridden value, such as making sure the authority matches the server's
    * TLS certificate.</em>
    */
   @Nullable
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1767")
   public String getAuthority() {
     return authority;
   }

   /**
    * Returns the call credentials.
    */
   @Nullable
   public CallCredentials getCredentials() {
     return credentials;
   }

   /**
    * Returns a new {@code CallOptions} with {@code executor} to be used instead of the default
    * executor specified with {@link ManagedChannelBuilder#executor}.
    */
   public CallOptions withExecutor(@Nullable Executor executor) {
     Builder builder = toBuilder(this);
     builder.executor = executor;
     return builder.build();
   }

   /**
    * Returns a new {@code CallOptions} with a {@code ClientStreamTracerFactory} in addition to
    * the existing factories.
    *
    * <p>This method doesn't replace existing factories, or try to de-duplicate factories.
    */
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/2861")
   public CallOptions withStreamTracerFactory(ClientStreamTracer.Factory factory) {
     ArrayList<ClientStreamTracer.Factory> newList =
         new ArrayList<>(streamTracerFactories.size() + 1);
     newList.addAll(streamTracerFactories);
     newList.add(factory);
     Builder builder = toBuilder(this);
     builder.streamTracerFactories = Collections.unmodifiableList(newList);
     return builder.build();
   }

   /**
    * Returns an immutable list of {@code ClientStreamTracerFactory}s.
    */
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/2861")
   public List<ClientStreamTracer.Factory> getStreamTracerFactories() {
     return streamTracerFactories;
   }

   /**
    * Key for a key-value pair. Uses reference equality.
    */
   public static final class Key<T> {
     private final String debugString;
     private final T defaultValue;

     private Key(String debugString, T defaultValue) {
       this.debugString = debugString;
       this.defaultValue = defaultValue;
     }

     /**
      * Returns the user supplied default value for this key.
      */
     public T getDefault() {
       return defaultValue;
     }

     @Override
     public String toString() {
       return debugString;
     }

     /**
      * Factory method for creating instances of {@link Key}.
      *
      * @param debugString a string used to describe this key, used for debugging.
      * @param defaultValue default value to return when value for key not set
      * @param <T> Key type
      * @return Key object
      * @deprecated Use {@link #create} or {@link #createWithDefault} instead. This method will
      *     be removed.
      */
     @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1869")
     @Deprecated
     public static <T> Key<T> of(String debugString, T defaultValue) {
       Preconditions.checkNotNull(debugString, "debugString");
       return new Key<>(debugString, defaultValue);
     }

     /**
      * Factory method for creating instances of {@link Key}. The default value of the
      * key is {@code null}.
      *
      * @param debugString a debug string that describes this key.
      * @param <T> Key type
      * @return Key object
      * @since 1.13.0
      */
     public static <T> Key<T> create(String debugString) {
       Preconditions.checkNotNull(debugString, "debugString");
       return new Key<>(debugString, /*defaultValue=*/ null);
     }

     /**
      * Factory method for creating instances of {@link Key}.
      *
      * @param debugString a debug string that describes this key.
      * @param defaultValue default value to return when value for key not set
      * @param <T> Key type
      * @return Key object
      * @since 1.13.0
      */
     public static <T> Key<T> createWithDefault(String debugString, T defaultValue) {
       Preconditions.checkNotNull(debugString, "debugString");
       return new Key<>(debugString, defaultValue);
     }
   }

   /**
    * Sets a custom option. Any existing value for the key is overwritten.
    *
    * @param key The option key
    * @param value The option value.
    * @since 1.13.0
    */
   public <T> CallOptions withOption(Key<T> key, T value) {
     Preconditions.checkNotNull(key, "key");
     Preconditions.checkNotNull(value, "value");

     Builder builder = toBuilder(this);
     int existingIdx = -1;
     for (int i = 0; i < customOptions.length; i++) {
       if (key.equals(customOptions[i][0])) {
         existingIdx = i;
         break;
       }
     }

     builder.customOptions = new Object[customOptions.length + (existingIdx == -1 ? 1 : 0)][2];
     System.arraycopy(customOptions, 0, builder.customOptions, 0, customOptions.length);

     if (existingIdx == -1) {
       // Add a new option
       builder.customOptions[customOptions.length] = new Object[] {key, value};
     } else {
       // Replace an existing option
       builder.customOptions[existingIdx] = new Object[] {key, value};
     }

     return builder.build();
   }

   /**
    * Get the value for a custom option or its inherent default.
    * @param key Key identifying option
    */
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1869")
   @SuppressWarnings("unchecked")
   public <T> T getOption(Key<T> key) {
     Preconditions.checkNotNull(key, "key");
     for (int i = 0; i < customOptions.length; i++) {
       if (key.equals(customOptions[i][0])) {
         return (T) customOptions[i][1];
       }
     }
     return key.defaultValue;
   }

   /**
    * Returns the executor override to use for this specific call, or {@code null} if there is no
    * override. The executor is only for servicing this one call, so is not safe to use after
    * {@link ClientCall.Listener#onClose}.
    */
   @Nullable
   public Executor getExecutor() {
     return executor;
   }

   /**
    * Returns whether <a href="https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md">
    * 'wait for ready'</a> option is enabled for the call. 'Fail fast' is the default option for gRPC
    * calls and 'wait for ready' is the opposite to it.
    */
   public boolean isWaitForReady() {
     return Boolean.TRUE.equals(waitForReady);
   }

   Boolean getWaitForReady() {
     return waitForReady;
   }

   /**
    * Sets the maximum allowed message size acceptable from the remote peer.  If unset, this will
    * default to the value set on the {@link ManagedChannelBuilder#maxInboundMessageSize(int)}.
    */
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
   public CallOptions withMaxInboundMessageSize(int maxSize) {
     checkArgument(maxSize >= 0, "invalid maxsize %s", maxSize);
     Builder builder = toBuilder(this);
     builder.maxInboundMessageSize = maxSize;
     return builder.build();
   }

   /**
    * Sets the maximum allowed message size acceptable sent to the remote peer.
    */
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
   public CallOptions withMaxOutboundMessageSize(int maxSize) {
     checkArgument(maxSize >= 0, "invalid maxsize %s", maxSize);
     Builder builder = toBuilder(this);
     builder.maxOutboundMessageSize = maxSize;
     return builder.build();
   }

   /**
    * Gets the maximum allowed message size acceptable from the remote peer.
    */
   @Nullable
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
   public Integer getMaxInboundMessageSize() {
     return maxInboundMessageSize;
   }

   /**
    * Gets the maximum allowed message size acceptable to send the remote peer.
    */
   @Nullable
   @ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
   public Integer getMaxOutboundMessageSize() {
     return maxOutboundMessageSize;
   }

   /**
    * Copy CallOptions.
    */
   private static Builder toBuilder(CallOptions other) {
     Builder builder = new Builder();
     builder.deadline = other.deadline;
     builder.executor = other.executor;
     builder.authority = other.authority;
     builder.credentials = other.credentials;
     builder.compressorName = other.compressorName;
     builder.customOptions = other.customOptions;
     builder.streamTracerFactories = other.streamTracerFactories;
     builder.waitForReady = other.waitForReady;
     builder.maxInboundMessageSize = other.maxInboundMessageSize;
     builder.maxOutboundMessageSize = other.maxOutboundMessageSize;
     return builder;
   }

   @Override
   public String toString() {
     return MoreObjects.toStringHelper(this)
         .add("deadline", deadline)
         .add("authority", authority)
         .add("callCredentials", credentials)
         .add("executor", executor != null ? executor.getClass() : null)
         .add("compressorName", compressorName)
         .add("customOptions", Arrays.deepToString(customOptions))
         .add("waitForReady", isWaitForReady())
         .add("maxInboundMessageSize", maxInboundMessageSize)
         .add("maxOutboundMessageSize", maxOutboundMessageSize)
         .add("streamTracerFactories", streamTracerFactories)
         .toString();
   }
 }
	/*
	* Copyright 2015 The gRPC Authors
	*
	* 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 io.grpc;

	import static com.google.common.base.Preconditions.checkArgument;

	import com.google.common.base.MoreObjects;
	import com.google.common.base.Preconditions;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Collections;
	import java.util.List;
	import java.util.concurrent.Executor;
	import java.util.concurrent.TimeUnit;
	import javax.annotation.CheckReturnValue;
	import javax.annotation.Nullable;
	import javax.annotation.concurrent.Immutable;

	/**
	* The collection of runtime options for a new RPC call.
	*
	* <p>A field that is not set is {@code null}.
	*/
	@Immutable
	@CheckReturnValue
	public final class CallOptions {
	/**
	* A blank {@code CallOptions} that all fields are not set.
	*/
	public static final CallOptions DEFAULT;

	static {
	Builder b = new Builder();
	b.customOptions = new Object[0][2];
	b.streamTracerFactories = Collections.emptyList();
	DEFAULT = b.build();
	}

	@Nullable
	private final Deadline deadline;

	@Nullable
	private final Executor executor;

	@Nullable
	private final String authority;

	@Nullable
	private final CallCredentials credentials;

	@Nullable
	private final String compressorName;

	private final Object[][] customOptions;

	private final List<ClientStreamTracer.Factory> streamTracerFactories;

	/**
	* Opposite to fail fast.
	*/
	@Nullable
	private final Boolean waitForReady;

	@Nullable
	private final Integer maxInboundMessageSize;
	@Nullable
	private final Integer maxOutboundMessageSize;

	private CallOptions(Builder builder) {
	this.deadline = builder.deadline;
	this.executor = builder.executor;
	this.authority = builder.authority;
	this.credentials = builder.credentials;
	this.compressorName = builder.compressorName;
	this.customOptions = builder.customOptions;
	this.streamTracerFactories = builder.streamTracerFactories;
	this.waitForReady = builder.waitForReady;
	this.maxInboundMessageSize = builder.maxInboundMessageSize;
	this.maxOutboundMessageSize = builder.maxOutboundMessageSize;
	}

	static class Builder {
	Deadline deadline;
	Executor executor;
	String authority;
	CallCredentials credentials;
	String compressorName;
	Object[][] customOptions;
	// Unmodifiable list
	List<ClientStreamTracer.Factory> streamTracerFactories;
	Boolean waitForReady;
	Integer maxInboundMessageSize;
	Integer maxOutboundMessageSize;

	private CallOptions build() {
	return new CallOptions(this);
	}
	}

	/**
	* Override the HTTP/2 authority the channel claims to be connecting to. <em>This is not
	* generally safe.</em> Overriding allows advanced users to re-use a single Channel for multiple
	* services, even if those services are hosted on different domain names. That assumes the
	* server is virtually hosting multiple domains and is guaranteed to continue doing so. It is
	* rare for a service provider to make such a guarantee. <em>At this time, there is no security
	* verification of the overridden value, such as making sure the authority matches the server's
	* TLS certificate.</em>
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1767")
	public CallOptions withAuthority(@Nullable String authority) {
	Builder builder = toBuilder(this);
	builder.authority = authority;
	return builder.build();
	}

	/**
	* Returns a new {@code CallOptions} with the given call credentials.
	*/
	public CallOptions withCallCredentials(@Nullable CallCredentials credentials) {
	Builder builder = toBuilder(this);
	builder.credentials = credentials;
	return builder.build();
	}

	/**
	* Sets the compression to use for the call. The compressor must be a valid name known in the
	* {@link CompressorRegistry}. By default, the "gzip" compressor will be available.
	*
	* <p>It is only safe to call this if the server supports the compression format chosen. There is
	* no negotiation performed; if the server does not support the compression chosen, the call will
	* fail.
	*/
	public CallOptions withCompression(@Nullable String compressorName) {
	Builder builder = toBuilder(this);
	builder.compressorName = compressorName;
	return builder.build();
	}

	/**
	* Returns a new {@code CallOptions} with the given absolute deadline.
	*
	* <p>This is mostly used for propagating an existing deadline. {@link #withDeadlineAfter} is the
	* recommended way of setting a new deadline,
	*
	* @param deadline the deadline or {@code null} for unsetting the deadline.
	*/
	public CallOptions withDeadline(@Nullable Deadline deadline) {
	Builder builder = toBuilder(this);
	builder.deadline = deadline;
	return builder.build();
	}

	/**
	* Returns a new {@code CallOptions} with a deadline that is after the given {@code duration} from
	* now.
	*/
	public CallOptions withDeadlineAfter(long duration, TimeUnit unit) {
	return withDeadline(Deadline.after(duration, unit));
	}

	/**
	* Returns the deadline or {@code null} if the deadline is not set.
	*/
	@Nullable
	public Deadline getDeadline() {
	return deadline;
	}

	/**
	* Enables <a href="https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md">
	* 'wait for ready'</a> for the call. Wait-for-ready queues the RPC until a connection is
	* available. This may dramatically increase the latency of the RPC, but avoids failing
	* "unnecessarily." The default queues the RPC until an attempt to connect has completed, but
	* fails RPCs without sending them if unable to connect.
	*/
	public CallOptions withWaitForReady() {
	Builder builder = toBuilder(this);
	builder.waitForReady = Boolean.TRUE;
	return builder.build();
	}

	/**
	* Disables 'wait for ready' feature for the call.
	* This method should be rarely used because the default is without 'wait for ready'.
	*/
	public CallOptions withoutWaitForReady() {
	Builder builder = toBuilder(this);
	builder.waitForReady = Boolean.FALSE;
	return builder.build();
	}

	/**
	* Returns the compressor's name.
	*/
	@Nullable
	public String getCompressor() {
	return compressorName;
	}

	/**
	* Override the HTTP/2 authority the channel claims to be connecting to. <em>This is not
	* generally safe.</em> Overriding allows advanced users to re-use a single Channel for multiple
	* services, even if those services are hosted on different domain names. That assumes the
	* server is virtually hosting multiple domains and is guaranteed to continue doing so. It is
	* rare for a service provider to make such a guarantee. <em>At this time, there is no security
	* verification of the overridden value, such as making sure the authority matches the server's
	* TLS certificate.</em>
	*/
	@Nullable
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1767")
	public String getAuthority() {
	return authority;
	}

	/**
	* Returns the call credentials.
	*/
	@Nullable
	public CallCredentials getCredentials() {
	return credentials;
	}

	/**
	* Returns a new {@code CallOptions} with {@code executor} to be used instead of the default
	* executor specified with {@link ManagedChannelBuilder#executor}.
	*/
	public CallOptions withExecutor(@Nullable Executor executor) {
	Builder builder = toBuilder(this);
	builder.executor = executor;
	return builder.build();
	}

	/**
	* Returns a new {@code CallOptions} with a {@code ClientStreamTracerFactory} in addition to
	* the existing factories.
	*
	* <p>This method doesn't replace existing factories, or try to de-duplicate factories.
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/2861")
	public CallOptions withStreamTracerFactory(ClientStreamTracer.Factory factory) {
	ArrayList<ClientStreamTracer.Factory> newList =
	new ArrayList<>(streamTracerFactories.size() + 1);
	newList.addAll(streamTracerFactories);
	newList.add(factory);
	Builder builder = toBuilder(this);
	builder.streamTracerFactories = Collections.unmodifiableList(newList);
	return builder.build();
	}

	/**
	* Returns an immutable list of {@code ClientStreamTracerFactory}s.
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/2861")
	public List<ClientStreamTracer.Factory> getStreamTracerFactories() {
	return streamTracerFactories;
	}

	/**
	* Key for a key-value pair. Uses reference equality.
	*/
	public static final class Key<T> {
	private final String debugString;
	private final T defaultValue;

	private Key(String debugString, T defaultValue) {
	this.debugString = debugString;
	this.defaultValue = defaultValue;
	}

	/**
	* Returns the user supplied default value for this key.
	*/
	public T getDefault() {
	return defaultValue;
	}

	@Override
	public String toString() {
	return debugString;
	}

	/**
	* Factory method for creating instances of {@link Key}.
	*
	* @param debugString a string used to describe this key, used for debugging.
	* @param defaultValue default value to return when value for key not set
	* @param <T> Key type
	* @return Key object
	* @deprecated Use {@link #create} or {@link #createWithDefault} instead. This method will
	* be removed.
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1869")
	@Deprecated
	public static <T> Key<T> of(String debugString, T defaultValue) {
	Preconditions.checkNotNull(debugString, "debugString");
	return new Key<>(debugString, defaultValue);
	}

	/**
	* Factory method for creating instances of {@link Key}. The default value of the
	* key is {@code null}.
	*
	* @param debugString a debug string that describes this key.
	* @param <T> Key type
	* @return Key object
	* @since 1.13.0
	*/
	public static <T> Key<T> create(String debugString) {
	Preconditions.checkNotNull(debugString, "debugString");
	return new Key<>(debugString, /defaultValue=/ null);
	}

	/**
	* Factory method for creating instances of {@link Key}.
	*
	* @param debugString a debug string that describes this key.
	* @param defaultValue default value to return when value for key not set
	* @param <T> Key type
	* @return Key object
	* @since 1.13.0
	*/
	public static <T> Key<T> createWithDefault(String debugString, T defaultValue) {
	Preconditions.checkNotNull(debugString, "debugString");
	return new Key<>(debugString, defaultValue);
	}
	}

	/**
	* Sets a custom option. Any existing value for the key is overwritten.
	*
	* @param key The option key
	* @param value The option value.
	* @since 1.13.0
	*/
	public <T> CallOptions withOption(Key<T> key, T value) {
	Preconditions.checkNotNull(key, "key");
	Preconditions.checkNotNull(value, "value");

	Builder builder = toBuilder(this);
	int existingIdx = -1;
	for (int i = 0; i < customOptions.length; i++) {
	if (key.equals(customOptions[i][0])) {
	existingIdx = i;
	break;
	}
	}

	builder.customOptions = new Object[customOptions.length + (existingIdx == -1 ? 1 : 0)][2];
	System.arraycopy(customOptions, 0, builder.customOptions, 0, customOptions.length);

	if (existingIdx == -1) {
	// Add a new option
	builder.customOptions[customOptions.length] = new Object[] {key, value};
	} else {
	// Replace an existing option
	builder.customOptions[existingIdx] = new Object[] {key, value};
	}

	return builder.build();
	}

	/**
	* Get the value for a custom option or its inherent default.
	* @param key Key identifying option
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1869")
	@SuppressWarnings("unchecked")
	public <T> T getOption(Key<T> key) {
	Preconditions.checkNotNull(key, "key");
	for (int i = 0; i < customOptions.length; i++) {
	if (key.equals(customOptions[i][0])) {
	return (T) customOptions[i][1];
	}
	}
	return key.defaultValue;
	}

	/**
	* Returns the executor override to use for this specific call, or {@code null} if there is no
	* override. The executor is only for servicing this one call, so is not safe to use after
	* {@link ClientCall.Listener#onClose}.
	*/
	@Nullable
	public Executor getExecutor() {
	return executor;
	}

	/**
	* Returns whether <a href="https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md">
	* 'wait for ready'</a> option is enabled for the call. 'Fail fast' is the default option for gRPC
	* calls and 'wait for ready' is the opposite to it.
	*/
	public boolean isWaitForReady() {
	return Boolean.TRUE.equals(waitForReady);
	}

	Boolean getWaitForReady() {
	return waitForReady;
	}

	/**
	* Sets the maximum allowed message size acceptable from the remote peer. If unset, this will
	* default to the value set on the {@link ManagedChannelBuilder#maxInboundMessageSize(int)}.
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
	public CallOptions withMaxInboundMessageSize(int maxSize) {
	checkArgument(maxSize >= 0, "invalid maxsize %s", maxSize);
	Builder builder = toBuilder(this);
	builder.maxInboundMessageSize = maxSize;
	return builder.build();
	}

	/**
	* Sets the maximum allowed message size acceptable sent to the remote peer.
	*/
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
	public CallOptions withMaxOutboundMessageSize(int maxSize) {
	checkArgument(maxSize >= 0, "invalid maxsize %s", maxSize);
	Builder builder = toBuilder(this);
	builder.maxOutboundMessageSize = maxSize;
	return builder.build();
	}

	/**
	* Gets the maximum allowed message size acceptable from the remote peer.
	*/
	@Nullable
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
	public Integer getMaxInboundMessageSize() {
	return maxInboundMessageSize;
	}

	/**
	* Gets the maximum allowed message size acceptable to send the remote peer.
	*/
	@Nullable
	@ExperimentalApi("https://github.com/grpc/grpc-java/issues/2563")
	public Integer getMaxOutboundMessageSize() {
	return maxOutboundMessageSize;
	}

	/**
	* Copy CallOptions.
	*/
	private static Builder toBuilder(CallOptions other) {
	Builder builder = new Builder();
	builder.deadline = other.deadline;
	builder.executor = other.executor;
	builder.authority = other.authority;
	builder.credentials = other.credentials;
	builder.compressorName = other.compressorName;
	builder.customOptions = other.customOptions;
	builder.streamTracerFactories = other.streamTracerFactories;
	builder.waitForReady = other.waitForReady;
	builder.maxInboundMessageSize = other.maxInboundMessageSize;
	builder.maxOutboundMessageSize = other.maxOutboundMessageSize;
	return builder;
	}

	@Override
	public String toString() {
	return MoreObjects.toStringHelper(this)
	.add("deadline", deadline)
	.add("authority", authority)
	.add("callCredentials", credentials)
	.add("executor", executor != null ? executor.getClass() : null)
	.add("compressorName", compressorName)
	.add("customOptions", Arrays.deepToString(customOptions))
	.add("waitForReady", isWaitForReady())
	.add("maxInboundMessageSize", maxInboundMessageSize)
	.add("maxOutboundMessageSize", maxOutboundMessageSize)
	.add("streamTracerFactories", streamTracerFactories)
	.toString();
	}
	}