InvalidURI.java:17: error: invalid uri: "abc def"
 * <a href="abc def">invalid</a>
      ^
InvalidURI.java:18: error: attribute lacks value
 * <a href>no value</a>
      ^
InvalidURI.java:19: error: attribute lacks value
 * <a href= >no value</a>
      ^
InvalidURI.java:20: error: attribute lacks value
 * <a href="" >no value</a>
      ^
4 errors