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How to redirect Ant output to a JTextArea

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How to redirect Ant output to a JTextArea

· Java Zone ·
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If you need to capture an Ant script output and resend it to an JTextArea (or similar components), you can try a few solutions. For my purposes I solved this task by writing a new logger that extends the DefaultLogger and overwrite the buildFinished, buildStarted and messageLogged methods:


class MyLogger extends DefaultLogger {

@Override
public void buildFinished(BuildEvent be) {
outputTextArea.append("[BUILD FINISHED]\n");
}

@Override
public void buildStarted(BuildEvent be) {
outputTextArea.append("[BUILD STARTED]\n");
}

@Override
public void messageLogged(BuildEvent be) {
outputTextArea.append(be.getMessage() + "\n");
}
}

Next, MyLogger was set to the current Project:
private boolean runAntScript(String scriptName) {

File buildFile = new File(scriptName);
Project project = new Project();
MyLogger myLogger = new MyLogger();

project.setUserProperty("ant.file", buildFile.getAbsolutePath());
myLogger.setErrorPrintStream(System.err);
myLogger.setOutputPrintStream(System.out);
myLogger.setMessageOutputLevel(Project.MSG_INFO);

project.addBuildListener(myLogger);

try {
project.fireBuildStarted();
project.init();
ProjectHelper helper = ProjectHelper.getProjectHelper();
project.addReference("ant.projectHelper", helper);
helper.parse(project, buildFile);
project.executeTarget(project.getDefaultTarget());
project.fireBuildFinished(null);
} catch (Exception e) {
project.fireBuildFinished(e);
return false;
}

return true;
}


Another solution is to implement the org.apache.tools.ant.BuildListener interface. This interface will force you to overwrite more methods but provide more control, as you can see below:
class myBuildListener implements org.apache.tools.ant.BuildListener  {

public void buildFinished(BuildEvent be) {
outputTextArea.append("[BUILD FINISHED]\n");
}

public void buildStarted(BuildEvent be) {
outputTextArea.append("[BUILD STARTED]\n");
}

public void messageLogged(BuildEvent be) {
outputTextArea.append(be.getMessage() + "\n");
}

public void targetFinished(BuildEvent be) {
throw new UnsupportedOperationException("Not supported yet.");
}

public void targetStarted(BuildEvent be) {
throw new UnsupportedOperationException("Not supported yet.");
}

public void taskFinished(BuildEvent be) {
throw new UnsupportedOperationException("Not supported yet.");
}

public void taskStarted(BuildEvent be) {
throw new UnsupportedOperationException("Not supported yet.");
}

}


Finally, a third solution is to send the Ant script output to a pipe:
private boolean runAntScript(String scriptName) {

PipedOutputStream pipeOut = null;
PipedInputStream pipeIn = null;
BufferedReader pipeReader = null;

try {
pipeOut = new PipedOutputStream();
pipeIn = new PipedInputStream(pipeOut);
pipeReader = new BufferedReader(new InputStreamReader(pipeIn));

System.setOut(new PrintStream(pipeOut));
System.setErr(new PrintStream(pipeOut));
} catch (IOException e) {
return false;
}

File buildFile = new File(scriptName);
Project project = new Project();
DefaultLogger consoleLogger = new DefaultLogger();

project.setUserProperty("ant.file", buildFile.getAbsolutePath());
consoleLogger.setErrorPrintStream(System.err);
consoleLogger.setOutputPrintStream(System.out);
consoleLogger.setMessageOutputLevel(Project.MSG_VERBOSE);
project.addBuildListener(new myBuildListener());

try {
project.fireBuildStarted();
project.init();
ProjectHelper helper = ProjectHelper.getProjectHelper();
project.addReference("ant.projectHelper", helper);
helper.parse(project, buildFile);
project.executeTarget(project.getDefaultTarget());
project.fireBuildFinished(null);
} catch (Exception e) {
project.fireBuildFinished(e);
return false;
}

return true;
}


Next, you will need a separate thread to read form pipe and put in the text area. This can be implemented through Java multi-threading capabilities in a few lines of code.


Well, there’s my solutions! Please fill free to bring other new and better ones.

From http://e-blog-java.blogspot.com/2011/04/how-to-redirect-ant-output-to-jtextarea.html

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