import org.apache.tools.ant.DemuxOutputStream; //导入依赖的package包/类
/**
 * Initializes an ant project. The base directory is the current working directory.
 * 
 * @return Ant project.
 */
private static Project buildProject() {
	Project project = new Project();
	project.setBasedir(System.getProperty("user.dir"));
	project.init();
	DefaultLogger logger = new DefaultLogger();
	project.addBuildListener(logger);
	logger.setOutputPrintStream(System.out);
	logger.setErrorPrintStream(System.err);
	logger.setMessageOutputLevel(Project.MSG_VERBOSE);
	System.setOut(new PrintStream(new DemuxOutputStream(project, false)));
	System.setErr(new PrintStream(new DemuxOutputStream(project, true)));
	project.fireBuildStarted();
	return project;
}
 

import org.apache.tools.ant.DemuxOutputStream; //导入依赖的package包/类
private void runBuild(File buildFile, Vector<String> targets, int messageLevel) throws BuildException {

        final Project project = new Project();
        project.setCoreLoader(null);

        Throwable error = null;

        try {
            addBuildListeners(project, messageLevel);
            addInputHandler(project, null);

            PrintStream err = System.err;
            PrintStream out = System.out;
            InputStream in = System.in;

            // use a system manager that prevents from System.exit()
            SecurityManager oldsm = null;
            oldsm = System.getSecurityManager();

            // SecurityManager can not be installed here for backwards
            // compatibility reasons (PD). Needs to be loaded prior to
            // ant class if we are going to implement it.
            // System.setSecurityManager(new NoExitSecurityManager());
            try {
                project.setDefaultInputStream(System.in);
                System.setIn(new DemuxInputStream(project));
                System.setOut(new PrintStream(new DemuxOutputStream(project, false)));
                System.setErr(new PrintStream(new DemuxOutputStream(project, true)));

                project.fireBuildStarted();

                project.init();
                project.setUserProperty("ant.version", Main.getAntVersion());

                project.setUserProperty("ant.file", buildFile.getAbsolutePath());

                ProjectHelper.configureProject(project, buildFile);

                // make sure that we have a target to execute
                if (targets.size() == 0 && project.getDefaultTarget() != null) {
                    targets.addElement(project.getDefaultTarget());
                }

                project.executeTargets(targets);
            } finally {
                // put back the original security manager
                // The following will never eval to true. (PD)
                if (oldsm != null) {
                    System.setSecurityManager(oldsm);
                }

                System.setOut(out);
                System.setErr(err);
                System.setIn(in);
            }
        } catch (RuntimeException | Error exc) {
            error = exc;
            throw exc;
        } finally {
            project.fireBuildFinished(error);
        }
    }
 

import org.apache.tools.ant.DemuxOutputStream; //导入依赖的package包/类
public static void main(String[] args) {
	// global ant project settings
	Project project = new Project();
	project.setBaseDir(new File(System.getProperty("user.dir")));
	project.init();
	DefaultLogger logger = new DefaultLogger();
	project.addBuildListener(logger);
	logger.setOutputPrintStream(System.out);
	logger.setErrorPrintStream(System.err);
	logger.setMessageOutputLevel(Project.MSG_INFO);
	System.setOut(new PrintStream(new DemuxOutputStream(project, false)));
	System.setErr(new PrintStream(new DemuxOutputStream(project, true)));
	project.fireBuildStarted();

	Throwable caught = null;
	try {
		// an echo example
		Echo echo = new Echo();
		echo.setTaskName("Echo");
		echo.setProject(project);
		echo.init();
		echo.setMessage("Launching ...");
		echo.execute();

		
		/** initialize an java task **/
		Java javaTask = new Java();
		javaTask.setNewenvironment(true);
		javaTask.setTaskName("runjava");
		javaTask.setProject(project);
		javaTask.setFork(true);
		javaTask.setFailonerror(true);
		javaTask.setClassname(MyClassToLaunch.class.getName());
		
		// add some vm args
		Argument jvmArgs = javaTask.createJvmarg();
		jvmArgs.setLine("-Xms512m -Xmx512m");
		
		// added some args for to class to launch
		Argument taskArgs = javaTask.createArg();
		taskArgs.setLine("bla path=/tmp/");
		
		Path classPath = new Path(project, new File(System.getProperty("user.dir") + "/bin/test").getAbsolutePath());
		javaTask.setClasspath(classPath);
		
		javaTask.init();
		int ret = javaTask.executeJava();
		System.out.println("return code: " + ret);

	} catch (BuildException e) {
		caught = e;
	}
	project.log("finished");
	project.fireBuildFinished(caught);
}