使用Ant作为顺手工具

source ： http://unserializableone.blogspot.com/2009/01/using-ant-as-library.html

Ant has a lot of predefined tasks that could be a great help. You can use them directly from your java code. Here are some examples using Ant to download a file, unzip a package and exec some shell command.

You would need to have
+ ant-1.7.1.jar
+ ant-launcher-1.7.1.jar
+ commons-io-1.3.2.jar (for exec example, found at http://commons.apache.org/io)

in your classpath.

publicclassAntDemo{

 /**
*DownloadafileatsourceUrltodest
*
*/
 publicstaticvoiddownload(URLsourceUrl,Filedest){
 ProjectdummyProject=newProject();
dummyProject.init();

 GetantGet=newGet();
antGet.setProject(dummyProject);
 antGet.setVerbose(true);
antGet.setSrc(sourceUrl);
antGet.setDest(dest);
antGet.execute();
}

 /**
*Unzipazipfile
*
*/
 publicstaticvoidunzip(Filesrc,Filedest){
 ProjectdummyProject=newProject();
dummyProject.init();

 ExpandantUnzip=newExpand();
antUnzip.setProject(dummyProject);
antUnzip.setSrc(src);
antUnzip.setDest(dest);
antUnzip.execute();

 /*antdoesn'tpreservepermissionbits
needtorestorethemmanually*/

 Chmodchmod=newChmod();
chmod.setProject(dummyProject);
 chmod.setDir(newFile(src.getAbsolutePath().replaceAll(".zip","")));
 chmod.setPerm("a+rx");
 chmod.setIncludes("**/**");
chmod.execute();
}


/**
 *RunashellcommandandreturntheoutputasString
*
*/
 publicstaticStringexec(Stringcommand,List<STRING>params,FileworkDir){
FileoutputFile;
 try{
 outputFile=File.createTempFile("exec",".out");
 }catch(IOExceptione){
 thrownewRuntimeException(e);
}

 ProjectdummyProject=newProject();
dummyProject.init();

 ExecTaskexecTask=newExecTask();
execTask.setProject(dummyProject);
execTask.setOutput(outputFile);
 execTask.setDir(workDir!=null?workDir:newFile(System
 .getProperty("user.dir")));
execTask.setExecutable(command);
 if(params!=null){
 for(Stringparam:params){
execTask.createArg().setValue(param);
}
}

execTask.execute();

 FileReaderreader=null;
 try{
 reader=newFileReader(outputFile);
 returnIOUtils.toString(reader);
 }catch(Exceptione){
 thrownewRuntimeException(e);
 }finally{
IOUtils.closeQuietly(reader);
outputFile.delete();
}
}

 publicstaticvoidmain(String[]args){
 List<STRING>params=Arrays.asList(newString[]{"Hello","World"});
 System.out.println(exec("echo",params,null));
}
}

public class AntDemo {

  /**
   * Download a file at sourceUrl to dest
   *
   */
  public static void download(URL sourceUrl, File dest) {
    Project dummyProject = new Project();
    dummyProject.init();

    Get antGet = new Get();
    antGet.setProject(dummyProject);
    antGet.setVerbose(true);
    antGet.setSrc(sourceUrl);
    antGet.setDest(dest);
    antGet.execute();
  }

  /**
   * Unzip a zip file
   *
   */
  public static void unzip(File src, File dest) {
    Project dummyProject = new Project();
    dummyProject.init();

    Expand antUnzip = new Expand();
    antUnzip.setProject(dummyProject);
    antUnzip.setSrc(src);
    antUnzip.setDest(dest);
    antUnzip.execute();

    /* ant doesn't preserve permission bits
       need to restore them manually */

    Chmod chmod = new Chmod();
    chmod.setProject(dummyProject);
    chmod.setDir(new File(src.getAbsolutePath().replaceAll(".zip", "")));
    chmod.setPerm("a+rx");
    chmod.setIncludes("**/**");
    chmod.execute();
  }


  /**
   * Run a shell command and return the output as String
   *  
   */
  public static String exec(String command, List params, File workDir) {
    File outputFile;
    try {
      outputFile = File.createTempFile("exec", ".out");
    } catch (IOException e) {
      throw new RuntimeException(e);
    }

    Project dummyProject = new Project();
    dummyProject.init();

    ExecTask execTask = new ExecTask();
    execTask.setProject(dummyProject);
    execTask.setOutput(outputFile);
    execTask.setDir(workDir != null ? workDir : new File(System
        .getProperty("user.dir")));
    execTask.setExecutable(command);
    if (params != null) {
      for (String param : params) {
        execTask.createArg().setValue(param);
      }
    }

    execTask.execute();

    FileReader reader = null;
    try {
      reader = new FileReader(outputFile);
      return IOUtils.toString(reader);
    } catch (Exception e) {
      throw new RuntimeException(e);
    } finally {
      IOUtils.closeQuietly(reader);
      outputFile.delete();
    }
  }

  public static void main(String[] args) {
    List params = Arrays.asList(new String[] { "Hello", "World" });
    System.out.println(exec("echo", params, null));
  }
}

Just note that you'll need a dummy project for the Ant task. Otherwise you'll get an NullPointerException.

There are a lot of tasks that you could use. The list is here http://ant.apache.org/manual/tasksoverview.html