source: trunk/JFCMonitor/src/de/ugoe/cs/eventbench/jfcmonitor/JFCListener.java @ 271

package de.ugoe.cs.eventbench.jfcmonitor;

import java.awt.AWTEvent;
import java.awt.Component;
import java.awt.event.AWTEventListener;
import java.awt.event.KeyEvent;
import java.awt.event.MouseEvent;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 * <p>
 * This class implements monitoring of AWT and Swing mouse and keyboard events.
 * Each of the events is written to an output stream.
 * </p>
 * 
 * @author Steffen Herbold
 * @version 1.0
 */
public class JFCListener implements AWTEventListener {

        /**
         * <p>
         * Convenience variable.
         * </p>
         */
        final static private String ENDLINE = System.getProperty("line.separator");

        /**
         * <p>
         * Writer for logging events.
         * </p>
         */
        final private OutputStreamWriter outputWriter;

        public JFCListener(OutputStreamWriter outputWriter) {
                this.outputWriter = outputWriter;
        }

        /**
         * <p>
         * Writes all received {@link MouseEvent}s and {@link KeyEvent}s to the
         * {@link #outputWriter}.
         * 
         * @see java.awt.event.AWTEventListener#eventDispatched(java.awt.AWTEvent)
         */
        @Override
        public void eventDispatched(AWTEvent event) {
                StringBuilder builder = new StringBuilder();

                if (event instanceof MouseEvent) {
                        MouseEvent mouseEvent = (MouseEvent) event;
                        if (!isMouseMovement(event.getID())) {
                                builder.append("<event id=\"" + event.getID() + "\">" + ENDLINE);
                                builder.append(" <param name=\"X\" value=\""
                                                + mouseEvent.getX() + "\" />" + ENDLINE);
                                builder.append(" <param name=\"Y\" value=\""
                                                + mouseEvent.getY() + "\" />" + ENDLINE);
                                builder.append(" <param name=\"Button\" value=\""
                                                + mouseEvent.getButton() + "\" />" + ENDLINE);
                                builder.append(" <param name=\"Modifiers\" value=\""
                                                + mouseEvent.getModifiers() + "\" />" + ENDLINE);
                                addSourceInfo(builder, event);
                                builder.append("</event>" + ENDLINE);
                        }
                }
                if (event instanceof KeyEvent) {
                        KeyEvent keyEvent = (KeyEvent) event;
                        if (keyEvent.getID() == KeyEvent.KEY_TYPED) {
                                builder.append("<event id=\"" + event.getID() + "\">" + ENDLINE);
                                builder.append(" <param name=\"KeyCode\" value=\""
                                                + keyEvent.getKeyCode() + "\" />" + ENDLINE);
                                builder.append(" <param name=\"Modifiers\" value=\""
                                                + keyEvent.getModifiers() + "\" />" + ENDLINE);
                                addSourceInfo(builder, event);
                                builder.append("</event>" + ENDLINE);
                        }
                }
                if (builder.length() > 0 && outputWriter != null) {
                        try {
                                outputWriter.write(builder.toString());
                                outputWriter.flush();
                        } catch (IOException e) {
                                System.err.println("JFCMONITOR -- Failure writing to log: "
                                                + e.getMessage());
                        }
                }
        }

        /**
         * <p>
         * Appends information about the event to a {@link StringBuilder}.
         * </p>
         * 
         * @param builder
         *            {@link StringBuilder} where the information is appended
         * @param event
         *            event whose information is appended
         */
        private void addSourceInfo(StringBuilder builder, AWTEvent event) {
                builder.append(" <param name=\"Source\" value=\""
                                + event.getSource().toString() + "\" />" + ENDLINE);
                if (event.getSource() instanceof Component) {
                        Component source = (Component) event.getSource();
                        addComponentInfo(builder, source, "Source");
                        addComponentInfo(builder, source.getParent(), "Parent");
                }
        }

        /**
         * <p>
         * Appends information about the component to the a {@link StringBuilder}.
         * The prefix can be used to give further information about the component.
         * </p>
         * 
         * @param builder
         *            {@link StringBuilder} where the information is appended
         * @param component
         *            component whose information is appended
         * @param prefix
         *            prefix to give further information about the component
         */
        private void addComponentInfo(StringBuilder builder, Component component,
                        String prefix) {
                builder.append(" <param name=\"" + prefix + "Name\" value=\""
                                + component.getName() + "\" />" + ENDLINE);
                for (Method method : component.getClass().getMethods()) {
                        try {
                                if (method.getName() == "getText") {
                                        String text = (String) method.invoke(component,
                                                        new Object[] {});
                                        builder.append(" <param name=\"" + prefix
                                                        + "Text\" value=\"" + text + "\" />" + ENDLINE);
                                }
                                if (method.getName() == "getTitle") {
                                        String title = (String) method.invoke(component,
                                                        new Object[] {});
                                        builder.append(" <param name=\"" + prefix
                                                        + "Title\" value=\"" + title + "\" />" + ENDLINE);
                                }
                        } catch (IllegalArgumentException e) {
                        } catch (IllegalAccessException e) {
                        } catch (InvocationTargetException e) {
                        }
                }
        }

        /**
         * <p>
         * Checks if the Id of an {@link AWTEvent} is a mouse movement Id.
         * </p>
         * 
         * @param eventId
         *            id of the {@link AWTEvent}
         * @return true, if the event is a mouse movement event; false otherwise
         */
        private boolean isMouseMovement(int eventId) {
                return eventId == MouseEvent.MOUSE_MOVED
                                || eventId == MouseEvent.MOUSE_DRAGGED
                                || eventId == MouseEvent.MOUSE_ENTERED
                                || eventId == MouseEvent.MOUSE_EXITED;
        }

}