Java example source code file (SourceTool.java)

This example Java source code file (SourceTool.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

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Java - Java tags/keywords

awt, breakpointrequest, commandinterpreter, dimension, event, exception, gui, jdi, jlist, jmenuitem, jpopupmenu, location, override, sourcelinerenderer, sourcemodel, sourcetoollistener, stmouselistener, string, swing

The SourceTool.java Java example source code

/*
 * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * This source code is provided to illustrate the usage of a given feature
 * or technique and has been deliberately simplified. Additional steps
 * required for a production-quality application, such as security checks,
 * input validation and proper error handling, might not be present in
 * this sample code.
 */


package com.sun.tools.example.debug.gui;

import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

import com.sun.jdi.*;
import com.sun.jdi.request.*;

import com.sun.tools.example.debug.bdi.*;

public class SourceTool extends JPanel {

    private static final long serialVersionUID = -5461299294186395257L;

    private Environment env;

    private ExecutionManager runtime;
    private ContextManager context;
    private SourceManager sourceManager;

    private JList list;
    private ListModel sourceModel;

    // Information on source file that is on display, or failed to be
    // displayed due to inaccessible source.  Used to update display
    // when sourcepath is changed.

    private String sourceName;          // relative path name, if showSourceFile
    private Location sourceLocn;        // location, if showSourceForLocation
    private CommandInterpreter interpreter;

    public SourceTool(Environment env) {

        super(new BorderLayout());

        this.env = env;

        runtime = env.getExecutionManager();
        sourceManager = env.getSourceManager();
        this.context = env.getContextManager();
        this.interpreter = new CommandInterpreter(env, true);

        sourceModel = new DefaultListModel();  // empty

        list = new JList(sourceModel);
        list.setCellRenderer(new SourceLineRenderer());

        list.setPrototypeCellValue(SourceModel.prototypeCellValue);

        SourceToolListener listener = new SourceToolListener();
        context.addContextListener(listener);
        runtime.addSpecListener(listener);
        sourceManager.addSourceListener(listener);

        MouseListener squeek = new STMouseListener();
        list.addMouseListener(squeek);

        add(new JScrollPane(list));
    }

    public void setTextFont(Font f) {
        list.setFont(f);
        list.setPrototypeCellValue(SourceModel.prototypeCellValue);
    }

    private class SourceToolListener
               implements ContextListener, SourceListener, SpecListener
    {

        // ContextListener

        @Override
        public void currentFrameChanged(CurrentFrameChangedEvent e) {
            showSourceContext(e.getThread(), e.getIndex());
        }

            // Clear source view.
            //      sourceModel = new DefaultListModel();  // empty

        // SourceListener

        @Override
        public void sourcepathChanged(SourcepathChangedEvent e) {
            // Reload source view if its contents depend
            // on the source path.
            if (sourceName != null) {
                showSourceFile(sourceName);
            } else if (sourceLocn != null) {
                showSourceForLocation(sourceLocn);
            }
        }

        // SpecListener

        @Override
        public void breakpointSet(SpecEvent e) {
            breakpointResolved(e);
        }

        @Override
        public void breakpointDeferred(SpecEvent e) { }

        @Override
        public void breakpointDeleted(SpecEvent e) {
            BreakpointRequest req = (BreakpointRequest)e.getEventRequest();
            Location loc = req.location();
            if (loc != null) {
                try {
                    SourceModel sm = sourceManager.sourceForLocation(loc);
                    sm.showBreakpoint(loc.lineNumber(), false);
                    showSourceForLocation(loc);
                } catch (Exception exc) {
                }
            }
        }

        @Override
        public void breakpointResolved(SpecEvent e) {
            BreakpointRequest req = (BreakpointRequest)e.getEventRequest();
            Location loc = req.location();
            try {
                SourceModel sm = sourceManager.sourceForLocation(loc);
                sm.showBreakpoint(loc.lineNumber(), true);
                showSourceForLocation(loc);
            } catch (Exception exc) {
            }
        }

        @Override
        public void breakpointError(SpecErrorEvent e) {
            breakpointDeleted(e);
        }

        @Override
        public void watchpointSet(SpecEvent e) {
        }
        @Override
        public void watchpointDeferred(SpecEvent e) {
        }
        @Override
        public void watchpointDeleted(SpecEvent e) {
        }
        @Override
        public void watchpointResolved(SpecEvent e) {
        }
        @Override
        public void watchpointError(SpecErrorEvent e) {
        }

        @Override
        public void exceptionInterceptSet(SpecEvent e) {
        }
        @Override
        public void exceptionInterceptDeferred(SpecEvent e) {
        }
        @Override
        public void exceptionInterceptDeleted(SpecEvent e) {
        }
        @Override
        public void exceptionInterceptResolved(SpecEvent e) {
        }
        @Override
        public void exceptionInterceptError(SpecErrorEvent e) {
        }
    }

    private void showSourceContext(ThreadReference thread, int index) {
        //### Should use ThreadInfo here.
        StackFrame frame = null;
        if (thread != null) {
            try {
                frame = thread.frame(index);
            } catch (IncompatibleThreadStateException e) {}
        }
        if (frame == null) {
            return;
        }
        Location locn = frame.location();
        /*****
        if (!showSourceForLocation(locn)) {
            env.notice("Could not display source for "
                       + Utils.locationString(locn));
        }
        *****/
        showSourceForLocation(locn);
    }

    public boolean showSourceForLocation(Location locn) {
        sourceName = null;
        sourceLocn = locn;
        int lineNo = locn.lineNumber();
        if (lineNo != -1) {
            SourceModel source = sourceManager.sourceForLocation(locn);
            if (source != null) {
                showSourceAtLine(source, lineNo-1);
                return true;
            }
        }
        // Here if we could not display source.
        showSourceUnavailable();
        return false;
    }

    public boolean showSourceFile(String fileName) {
        sourceLocn = null;
        File file;
        if (!fileName.startsWith(File.separator)) {
            sourceName = fileName;
            SearchPath sourcePath = sourceManager.getSourcePath();
            file = sourcePath.resolve(fileName);
            if (file == null) {
                //env.failure("Source not found on current source path.");
                showSourceUnavailable();
                return false;
            }
        } else {
            sourceName = null;  // Absolute pathname does not depend on sourcepath.
            file = new File(fileName);
        }
        SourceModel source = sourceManager.sourceForFile(file);
        if (source != null) {
            showSource(source);
            return true;
        }
        showSourceUnavailable();
        return false;
    }

    private void showSource(SourceModel model) {
        setViewModel(model);
    }

    private void showSourceAtLine(SourceModel model, int lineNo) {
        setViewModel(model);
        if (model.isActuallySource && (lineNo < model.getSize())) {
            list.setSelectedIndex(lineNo);
            if (lineNo+4 < model.getSize()) {
                list.ensureIndexIsVisible(lineNo+4);  // give some context
            }
            list.ensureIndexIsVisible(lineNo);
        }
    }

    private void showSourceUnavailable() {
        SourceModel model = new SourceModel("[Source code is not available]");
        setViewModel(model);
    }

    private void setViewModel(SourceModel model) {
        if (model != sourceModel) {
            // install new model
            list.setModel(model);
            sourceModel = model;
        }
    }

    private class SourceLineRenderer extends DefaultListCellRenderer {

        @Override
        public Component getListCellRendererComponent(JList list,
                                                      Object value,
                                                      int index,
                                                      boolean isSelected,
                                                      boolean cellHasFocus) {

            //### Should set background highlight and/or icon if breakpoint on this line.
            // Configures "this"
            super.getListCellRendererComponent(list, value, index,
                                               isSelected, cellHasFocus);

            SourceModel.Line line = (SourceModel.Line)value;

            //### Tab expansion is now done when source file is read in,
            //### to speed up display.  This costs a lot of space, slows
            //### down source file loading, and has not been demonstrated
            //### to yield an observable improvement in display performance.
            //### Measurements may be appropriate here.
            //String sourceLine = expandTabs((String)value);
            setText(line.text);
            if (line.hasBreakpoint) {
                setIcon(Icons.stopSignIcon);
            } else if (line.isExecutable()) {
                setIcon(Icons.execIcon);
            } else {
                setIcon(Icons.blankIcon);
            }


            return this;
        }

        @Override
        public Dimension getPreferredSize() {
            Dimension dim = super.getPreferredSize();
            return new Dimension(dim.width, dim.height-5);
        }

    }

    private class STMouseListener extends MouseAdapter implements MouseListener {
        @Override
        public void mousePressed(MouseEvent e) {
            if (e.isPopupTrigger()) {
                showPopupMenu((Component)e.getSource(),
                              e.getX(), e.getY());
            }
        }

        @Override
        public void mouseReleased(MouseEvent e) {
            if (e.isPopupTrigger()) {
                showPopupMenu((Component)e.getSource(),
                              e.getX(), e.getY());
            }
        }

        private void showPopupMenu(Component invoker, int x, int y) {
            JList list = (JList)invoker;
            int ln = list.getSelectedIndex() + 1;
            SourceModel.Line line =
                (SourceModel.Line)list.getSelectedValue();
            JPopupMenu popup = new JPopupMenu();

            if (line == null) {
                popup.add(new JMenuItem("please select a line"));
            } else if (line.isExecutable()) {
                String className = line.refType.name();
                if (line.hasBreakpoint()) {
                    popup.add(commandItem("Clear Breakpoint",
                                          "clear " + className +
                                          ":" + ln));
                } else {
                    popup.add(commandItem("Set Breakpoint",
                                          "stop at " + className +
                                          ":" + ln));
                }
            } else {
                popup.add(new JMenuItem("not an executable line"));
            }

            popup.show(invoker,
                       x + popup.getWidth()/2, y + popup.getHeight()/2);
        }

        private JMenuItem commandItem(String label, final String cmd) {
            JMenuItem item = new JMenuItem(label);
            item.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    interpreter.executeCommand(cmd);
                }
            });
            return item;
        }
    }
}