Each language port of Diff Match Patch uses the same API. These are the language-specific notes regarding Java.

Before starting, go to the java directory, and create an empty sub-directory called classes.

Here's a minimal example of a diff in Java:

import java.util.LinkedList;
import name.fraser.neil.plaintext.diff_match_patch;
public class hello {
  public static void main(String args[]) {
    diff_match_patch dmp = new diff_match_patch();
    LinkedList<diff_match_patch.Diff> diff = dmp.diff_main("Hello World.", "Goodbye World.");
    // Result: [(-1, "Hell"), (1, "G"), (0, "o"), (1, "odbye"), (0, " World.")]
    dmp.diff_cleanupSemantic(diff);
    // Result: [(-1, "Hello"), (1, "Goodbye"), (0, " World.")]
    System.out.println(diff);
  }
}

Go to the java/src directory and save the above program as hello.java. Then go to the java directory and execute these two commands:

javac -d classes src/name/fraser/neil/plaintext/diff_match_patch.java src/hello.java
java -classpath classes hello

Unit tests can be performed from the java directory by executing two commands:

javac -d classes src/name/fraser/neil/plaintext/diff_match_patch.java tests/name/fraser/neil/plaintext/diff_match_patch_test.java
java -classpath classes name/fraser/neil/plaintext/diff_match_patch_test

All tests should pass.

Speed test for diff can be performed from the java directory by executing two commands:

javac -d classes src/name/fraser/neil/plaintext/diff_match_patch.java tests/name/fraser/neil/plaintext/Speedtest.java
java -classpath classes name/fraser/neil/plaintext/Speedtest