Java sax example

Hello All
I need a xml, sax example.....
If I have a XML document like
Input.xml
<film>
     <artistes>
          <name>Art1</name>
          <name>Art2</name>
     <artistes>
     <technicians>
          <tech> Camera </tech>
          <tech> Direction </tech>
     <technicians>
</film>
I want the xml to be verified against a DTD (please come up with the DTD for the above xml, sorry). And the output xml should be of the form
<finearts>
     <artistes>
          <name>Art1</name>
          <name>Art2</name>
     <artistes>
     <technicians>
          <tech> Camera </tech>
          <tech> Direction </tech>
     <technicians>
<finearts>
Basically film node is replaced by finearts.
I can appreciate if I can get a java program which does this.
The java class should have 2 methods, one whch takes input xml as string, and the other which takes as filename. I need this to be using SAX parser.
Repeating
1. Take xmlinput either as a string or as a file.
2. Validate against DTD.
3. Perform the transform.
4. Write the result to a file.
Thanks

Forte can auto generate a sax parser for you. Just mount the correct directory and right click on the dtd, and select SAX handler wizard.

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        if (tail == null) {
            head = null;
        else {
            tail.next = null;
        length--;
        return elt.obj;
    public synchronized boolean isEmpty() {
        return (tail == null);
    public final synchronized Enumeration elements() {
        return new LIFOQueueEnumerator(this);
    public final synchronized Enumeration reverseElements() {
        return new FIFOQueueEnumerator(this);
    public synchronized void dump(String msg) {
        System.err.println(">> " + msg);
        System.err.println(
                + length
                + " elt(s); head = "
                + (head == null ? "null" : (head.obj) + "")
                + " tail = "
                + (tail == null ? "null" : (tail.obj) + ""));
        QueueElement cursor = head;
        QueueElement last = null;
        while (cursor != null) {
            System.err.println(" " + cursor);
            last = cursor;
            cursor = cursor.next;
        if (last != tail) {
            System.err.println(" tail != last: " + tail + ", " + last);
        System.err.println("]");
QueueException.java
package thread.util;
public class QueueException extends RuntimeException {
ThreadPool.java
package thread.util;
* A thread pool with a bounded task queue and fixed number of worker threads.
public class ThreadPool {
    public static ThreadPool currentThreadPool = null;
    public Queue queue;
    public ThreadPool(int threads) {
        queue = new Queue();
        /* create the worker threads */
        for (int i = 0; i < threads; ++i) {
            Thread t = new Thread(new WorkerThread(), "WorkerThread: " + (i + 1));
            t.setDaemon(true);
            t.start();
     * Queues a task to be executed by this ThreadPool. If the task queue is
     * full, the task will run in the calling thread. (Could easily be modified
     * to throw an exception instead.)
    public void doTask(Runnable task) {
        synchronized (queue) {
            queue.enqueue(task);
            queue.notify();
     * Tests if the task queue is empty. Useful if you want to wait for all
     * queued tasks to complete before terminating your program.
    public boolean queueEmpty() {
        synchronized (queue) {
            return queue.isEmpty();
    private class WorkerThread implements Runnable {
        public void run() {
            Runnable task;
            while (true) {
                task = null;
                synchronized (queue) {
                    try {
                        if (queue.isEmpty()) {
                            queue.wait();
                        else {
                            task = (Runnable)queue.dequeue();
                    catch (InterruptedException e) {
                        break;
                if (task != null) {
                    task.run();
    } /* end inner class WorkerThread */
    public static void invokeLater(ThreadPool thp, Runnable task) {
        thp.doTask(task);
    public static void invokeAndWait(ThreadPool thp, Runnable task) {
        TaskWrapper tw = new TaskWrapper(task);
        synchronized(tw.task) {
            try {
                thp.doTask(tw);
                tw.task.wait();
            catch (InterruptedException e) {
            tw = null;
    public static void invokeLater(Runnable task) {
        if(ThreadPool.currentThreadPool == null) {
            ThreadPool.currentThreadPool = new ThreadPool(20);
        ThreadPool.currentThreadPool.doTask(task);
    public static void invokeAndWait(Runnable task) {
        if(ThreadPool.currentThreadPool == null) {
            ThreadPool.currentThreadPool = new ThreadPool(20);
        TaskWrapper tw = new TaskWrapper(task);
        synchronized(tw.task) {
            try {
                ThreadPool.currentThreadPool.doTask(tw);
                tw.task.wait();
            catch (InterruptedException e) {
            tw = null;
} /* end class ThreadPool */
class TaskWrapper implements Runnable {
    public Runnable task;
    public TaskWrapper(Runnable task) {
        this.task = task;
    public void run() {
        synchronized(task) {
            task.run();
            task.notify();

Thanks for the example. I was wondering how to do this.
I am running it right now on Fedora Linux.
When I run the demo TPTest.java
as written
ThreadPool thp = new ThreadPool(100);
int count = 10000;
I get and error at the very end of the run like this :
Sample No.10000     32:36:289:Executed: Task No.652Thread[WorkerThread: 10,5,main]
java.io.IOException: Stream closed
     at sun.nio.cs.StreamEncoder.ensureOpen(StreamEncoder.java:38)
     at sun.nio.cs.StreamEncoder.flush(StreamEncoder.java:151)
     at java.io.OutputStreamWriter.flush(OutputStreamWriter.java:213)
     at demo.test.ShutdownHook.run(TPTest.java:14)
Is this correct behaviour?
General this the only error I see. If I start changing the count and Threadpool size to
other combinations, I occasionally get other errors similar to this one as well.
java.io.IOException: Stream closed
     at sun.nio.cs.StreamEncoder.ensureOpen(StreamEncoder.java:38)
     at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:129)
     at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:146)
     at java.io.OutputStreamWriter.write(OutputStreamWriter.java:204)
     at java.io.Writer.write(Writer.java:126)
     at demo.test.MyRunnable.run(TPTest.java:53)
     at thread.util.ThreadPool$WorkerThread.run(ThreadPool.java:58)
     at java.lang.Thread.run(Thread.java:534)
Is there a way to increase thread size with java on Fedora Linux (Core 3)?
Would like to know. This example was interesting to me because I am trying to push
the limit for load testing purposes.
Thanks again for the example. Let me know if you have any updates to this one.

Berkeley DB master-slave replication basic java code example

Hi,
I am new user of berkeley db and I have limited knowledge of Java programming. Can someone help me with basic Java example code of how to do master-slave replication without elections.
Thanx,
Jani

Hello,
Please clarify a few points about your program:
1. What platform and Berkeley DB version are you using?
2. Are you planning on using the replication framework
or base replication API for your application?
3. When you say you want replication without elections,
what exactly does that mean. For example, if you are using
the replication framework elections are held transparently
without any input from your application's code. In this case,
DB will determine which environment is the master and which
are replicas. Is that what you are thinking about or
something else?
Thanks,
Sandra

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