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jBiDiB BiDiB Wizard Client Application POM
There is a newer version: 2.0.29
/**
 * License unknown.
 * based on  Alexander Potochkin's "Debugging Swing, the final summary"
 * when oracle acquired sun, this blog post was removed, and lives only in copies.
 * most complex was found: http://web.archive.org/web/20150523152453/https://weblogs.java.net/blog/alexfromsun/archive/2006/02/debugging_swing.html
 */
package org.bidib.wizard.utils;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;

import javax.swing.JComponent;
import javax.swing.RepaintManager;
import javax.swing.SwingUtilities;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * For usage of this class, please refer to
 * http://weblogs.java.net/blog/alexfromsun/archive/2006/02/debugging_swing.html
 * 
 * To use it, call RepaintManager.setCurrentManager(new ThreadCheckingRepaintManager()) then watch the print out from
 * the console of all threading violations.
 * 
 */
public final class ThreadCheckingRepaintManager extends RepaintManager {

    private static final Logger LOGGER = LoggerFactory.getLogger(ThreadCheckingRepaintManager.class);

    // it is recommended to pass the complete check
    private boolean completeCheck = true;

    private boolean checkIsShowing = false;

    /**
     * Creates ThreadCheckingRepaintManager. You can create one and set it using RepaintManager.setCurrentManager(new
     * ThreadCheckingRepaintManager()).
     */
    public ThreadCheckingRepaintManager() {
        super();
    }

    /**
     * Creates ThreadCheckingRepaintManager. You can create one and set it using RepaintManager.setCurrentManager(new
     * ThreadCheckingRepaintManager()).
     *
     * @param checkIsShowing
     *            true to only check showing components.
     */
    public ThreadCheckingRepaintManager(final boolean checkIsShowing) {
        super();
        this.checkIsShowing = checkIsShowing;
    }

    /**
     * Initially there was a rule that it is safe to create and use Swing components until they are realized but this
     * rule is not valid any more, and now it is recommended to interact with Swing from EDT only.
     * 
     * That's why completeCheck flag is used - if you test the old program switch it to false, but new applications
     * should be tested with completeCheck set to true*
     *
     * @return true or false. By default, it is false.
     */
    public boolean isCompleteCheck() {
        return completeCheck;
    }

    /**
     * @param completeCheck
     *            true or false.
     *
     * @see #isCompleteCheck()
     */
    public void setCompleteCheck(final boolean completeCheck) {
        this.completeCheck = completeCheck;
    }

    @Override
    public synchronized void addInvalidComponent(final JComponent jComponent) {
        checkThreadViolations(jComponent);
        super.addInvalidComponent(jComponent);
    }

    @Override
    public synchronized void addDirtyRegion(
        final JComponent jComponent, final int x, final int y, final int width, final int height) {
        checkThreadViolations(jComponent);
        super.addDirtyRegion(jComponent, x, y, width, height);
    }

    private void checkThreadViolations(final JComponent c) {
        if (!SwingUtilities.isEventDispatchThread() && (completeCheck || checkIsShowing(c))) {
            final Exception exception = new Exception();
            boolean repaint = false;
            boolean fromSwing = false;
            final StackTraceElement[] stackTrace = exception.getStackTrace();
            for (final StackTraceElement st : stackTrace) {
                if (repaint && st.getClassName().startsWith("javax.swing.")) {
                    fromSwing = true;
                }
                if ("repaint".equals(st.getMethodName())) {
                    repaint = true;
                }
            }
            if (repaint && !fromSwing) {
                // no problems here, since repaint() is thread safe
                return;
            }
            LOGGER.warn("----------Wrong Thread START");
            LOGGER.warn(getStrackTraceAsString(exception));
            LOGGER.warn("----------Wrong Thread END");
        }
    }

    @SuppressWarnings({ "SimplifiableIfStatement" })
    private boolean checkIsShowing(final JComponent c) {
        if (this.checkIsShowing) {
            return c.isShowing();
        }
        else {
            return true;
        }
    }

    private String getStrackTraceAsString(final Exception e) {
        final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        final PrintStream printStream = new PrintStream(byteArrayOutputStream);
        e.printStackTrace(printStream);
        printStream.flush();
        return byteArrayOutputStream.toString();
    }
}