org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/snippeteditor/ScrapbookLauncher.java - jdt/eclipse.jdt.debug - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2015 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.jdt.internal.debug.ui.snippeteditor;


 import java.io.File;
 import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLEncoder;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.StringTokenizer;

 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.resources.IWorkspaceRoot;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.FileLocator;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Path;
 import org.eclipse.core.runtime.QualifiedName;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.debug.core.DebugEvent;
 import org.eclipse.debug.core.DebugPlugin;
 import org.eclipse.debug.core.IDebugEventSetListener;
 import org.eclipse.debug.core.ILaunch;
 import org.eclipse.debug.core.ILaunchConfiguration;
 import org.eclipse.debug.core.ILaunchConfigurationType;
 import org.eclipse.debug.core.ILaunchConfigurationWorkingCopy;
 import org.eclipse.debug.core.ILaunchManager;
 import org.eclipse.debug.core.model.IBreakpoint;
 import org.eclipse.debug.core.model.IDebugTarget;
 import org.eclipse.debug.ui.IDebugUIConstants;
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.core.ToolFactory;
 import org.eclipse.jdt.core.compiler.CharOperation;
 import org.eclipse.jdt.core.util.IClassFileReader;
 import org.eclipse.jdt.core.util.ICodeAttribute;
 import org.eclipse.jdt.core.util.ILineNumberAttribute;
 import org.eclipse.jdt.core.util.IMethodInfo;
 import org.eclipse.jdt.debug.core.IJavaLineBreakpoint;
 import org.eclipse.jdt.debug.core.JDIDebugModel;
 import org.eclipse.jdt.debug.ui.IJavaDebugUIConstants;
 import org.eclipse.jdt.internal.debug.ui.JDIDebugUIPlugin;
 import org.eclipse.jdt.internal.launching.JavaMigrationDelegate;
 import org.eclipse.jdt.launching.IJavaLaunchConfigurationConstants;
 import org.eclipse.jdt.launching.IRuntimeClasspathEntry;
 import org.eclipse.jdt.launching.IVMInstall;
 import org.eclipse.jdt.launching.JavaRuntime;
 import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.osgi.util.NLS;

 /**
  * Support for launching scrapbook using launch configurations.
  */

 public class ScrapbookLauncher implements IDebugEventSetListener {

 	public static final String SCRAPBOOK_LAUNCH = IJavaDebugUIConstants.PLUGIN_ID + ".scrapbook_launch"; //$NON-NLS-1$

 	public static final String SCRAPBOOK_FILE_PATH = IJavaDebugUIConstants.PLUGIN_ID + ".scrapbook_file_path"; //$NON-NLS-1$

 	/**
 	 * Persistent property associated with snippet files specifying working directory.
 	 * Same format as the associated launch configuration attribute
 	 * <code>ATTR_WORKING_DIR</code>.
 	 */
 	public static final QualifiedName SNIPPET_EDITOR_LAUNCH_CONFIG_HANDLE_MEMENTO = new QualifiedName(IJavaDebugUIConstants.PLUGIN_ID, "snippet_editor_launch_config"); //$NON-NLS-1$

 	private IJavaLineBreakpoint fMagicBreakpoint;

 	private HashMap<IFile, IDebugTarget> fScrapbookToVMs = new HashMap<>(10);
 	private HashMap<IDebugTarget, IBreakpoint> fVMsToBreakpoints = new HashMap<>(10);
 	private HashMap<IDebugTarget, IFile> fVMsToScrapbooks = new HashMap<>(10);

 	private static ScrapbookLauncher fgDefault = null;

 	private ScrapbookLauncher() {
 		//see getDefault()
 	}

 	public static ScrapbookLauncher getDefault() {
 		if (fgDefault == null) {
 			fgDefault = new ScrapbookLauncher();
 		}
 		return fgDefault;
 	}

 	/**
 	 * Launches a VM for the given scrapbook page, in debug mode.
 	 * Returns an existing launch if the page is already running.
 	 * @param page the scrapbook page file
 	 *
 	 * @return resulting launch, or <code>null</code> on failure
 	 */
 	protected ILaunch launch(IFile page) {

 		// clean up orphaned launch configurations
 		cleanupLaunchConfigurations();

 		if (!page.getFileExtension().equals("jpage")) { //$NON-NLS-1$
 			showNoPageDialog();
 			return null;
 		}

 		IDebugTarget vm = getDebugTarget(page);
 		if (vm != null) {
 			//already launched
 			return vm.getLaunch();
 		}

 		IJavaProject javaProject= JavaCore.create(page.getProject());

 		URL jarURL = null;
 		try {
 			jarURL = JDIDebugUIPlugin.getDefault().getBundle().getEntry("snippetsupport.jar"); //$NON-NLS-1$
 			jarURL = FileLocator.toFileURL(jarURL);
 		} catch (MalformedURLException e) {
 			JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
 			return null;
 		} catch (IOException e) {
 			JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
 			return null;
 		}

 		List<IRuntimeClasspathEntry> cp = new ArrayList<>(3);
 		String jarFile = jarURL.getFile();
 		IRuntimeClasspathEntry supportEntry = JavaRuntime.newArchiveRuntimeClasspathEntry(new Path(jarFile));
 		cp.add(supportEntry);
 		// get bootpath entries
 		try {
 			IRuntimeClasspathEntry[] entries = JavaRuntime.computeUnresolvedRuntimeClasspath(javaProject);
 			for (int i = 0; i < entries.length; i++) {
 				if (entries[i].getClasspathProperty() != IRuntimeClasspathEntry.USER_CLASSES) {
 					cp.add(entries[i]);
 				}
 			}
 			IRuntimeClasspathEntry[] classPath = cp.toArray(new IRuntimeClasspathEntry[cp.size()]);

 			return doLaunch(javaProject, page, classPath, jarFile);
 		} catch (CoreException e) {
 			JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
 		}
 		return null;
 	}

 	private ILaunch doLaunch(IJavaProject p, IFile page, IRuntimeClasspathEntry[] classPath, String jarFile) {
 		try {
 			if (fVMsToScrapbooks.isEmpty()) {
 				// register for debug events if a scrapbook is not currently running
 				DebugPlugin.getDefault().addDebugEventListener(this);
 			}
 			ILaunchConfiguration config = null;
 			ILaunchConfigurationWorkingCopy wc = null;
 			try {
 				config = getLaunchConfigurationTemplate(page);
 				if (config != null) {
 					wc = config.getWorkingCopy();
 				}
 			} catch (CoreException e) {
 				config = null;
 				JDIDebugUIPlugin.errorDialog("Unable to retrieve scrapbook settings", e); //$NON-NLS-1$
 			}

 			if (config == null) {
 				config = createLaunchConfigurationTemplate(page);
 				wc = config.getWorkingCopy();
 			}

 			IPath outputLocation =	p.getProject().getWorkingLocation(JDIDebugUIPlugin.getUniqueIdentifier());
 			File f = outputLocation.toFile();
 			URL u = null;
 			try {
 				u = getEncodedURL(f);
 			} catch (MalformedURLException e) {
 				JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
 				return null;
 			}
 			catch(UnsupportedEncodingException usee) {
 				JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", usee); //$NON-NLS-1$
 				return null;
 			}
 			String[] defaultClasspath = JavaRuntime.computeDefaultRuntimeClassPath(p);
 			String[] urls = new String[defaultClasspath.length + 1];
 			urls[0] = u.toExternalForm();
 			for (int i = 0; i < defaultClasspath.length; i++) {
 				f = new File(defaultClasspath[i]);
 				try {
 					urls[i + 1] = getEncodedURL(f).toExternalForm();
 				} catch (MalformedURLException e) {
 					JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e);				 //$NON-NLS-1$
 				 	return null;
 				}
 				catch(UnsupportedEncodingException usee) {
 					JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", usee); //$NON-NLS-1$
 					return null;
 				}
 			}

 			// convert to mementos
 			List<String> classpathList= new ArrayList<>(classPath.length);
 			for (int i = 0; i < classPath.length; i++) {
 				classpathList.add(classPath[i].getMemento());
 			}
 			if(wc == null) {
 				wc = config.getWorkingCopy();
 			}
 			wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_DEFAULT_CLASSPATH, false);
 			wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_CLASSPATH, classpathList);
 			wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROJECT_NAME, p.getElementName());
 			if (wc.getAttribute(IJavaLaunchConfigurationConstants.ATTR_SOURCE_PATH_PROVIDER, (String)null) == null) {
 				wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_SOURCE_PATH_PROVIDER, "org.eclipse.jdt.debug.ui.scrapbookSourcepathProvider"); //$NON-NLS-1$
 			}

 			StringBuffer urlsString = new StringBuffer();
 			for (int i = 0; i < urls.length; i++) {
 				urlsString.append(' ');
 				urlsString.append(urls[i]);
 			}
 			wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROGRAM_ARGUMENTS, urlsString.toString());
 			wc.setAttribute(SCRAPBOOK_LAUNCH, SCRAPBOOK_LAUNCH);

 			config = wc.doSave();

 			ILaunch launch = config.launch(ILaunchManager.DEBUG_MODE, null);
 			if (launch != null) {
 				IDebugTarget dt = launch.getDebugTarget();
 				IBreakpoint magicBreakpoint = createMagicBreakpoint(jarFile);
 				fScrapbookToVMs.put(page, dt);
 				fVMsToScrapbooks.put(dt, page);
 				fVMsToBreakpoints.put(dt, magicBreakpoint);
 				dt.breakpointAdded(magicBreakpoint);
 				launch.setAttribute(SCRAPBOOK_LAUNCH, SCRAPBOOK_LAUNCH);
 				return launch;
 			}
 		} catch (CoreException e) {
 			JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
 		}
 		return null;
 	}

 	/**
 	 * Creates an "invisible" line breakpoint.
 	 *
 	 * @param jarFile
 	 *            path to the snippetsupport.jar file
 	 * @return the new 'magic' breakpoint
 	 * @throws CoreException
 	 *             if an exception occurs
 	 */
 	IBreakpoint createMagicBreakpoint(String jarFile) throws CoreException {
 		// set a breakpoint on the "Thread.sleep(100);" line of the "ScrapbookMainnop()" method
 		String typeName = "org.eclipse.jdt.internal.debug.ui.snippeteditor.ScrapbookMain"; //$NON-NLS-1$

 		IClassFileReader reader = ToolFactory.createDefaultClassFileReader(jarFile, typeName.replace('.', '/')
 				+ ".class", IClassFileReader.METHOD_INFOS | IClassFileReader.METHOD_BODIES); //$NON-NLS-1$
 		IMethodInfo[] methodInfos = reader.getMethodInfos();
 		for (IMethodInfo methodInfo : methodInfos) {
 			if (!CharOperation.equals("nop".toCharArray(), methodInfo.getName())) {//$NON-NLS-1$
 				continue;
 			}
 			ICodeAttribute codeAttribute = methodInfo.getCodeAttribute();
 			ILineNumberAttribute lineNumberAttribute = codeAttribute.getLineNumberAttribute();
 			int[][] lineNumberTable = lineNumberAttribute.getLineNumberTable();
 			int lineNumber = lineNumberTable[0][1];

 			fMagicBreakpoint = JDIDebugModel.createLineBreakpoint(ResourcesPlugin.getWorkspace().getRoot(), typeName, lineNumber, -1, -1, 0, false, null);
 			fMagicBreakpoint.setPersisted(false);
 			return fMagicBreakpoint;
 		}
 		throw new CoreException(new Status(IStatus.ERROR, JDIDebugUIPlugin.getUniqueIdentifier(), IJavaDebugUIConstants.INTERNAL_ERROR, "An error occurred creating the evaluation breakpoint location.", null)); //$NON-NLS-1$
 	}

 	/**
 	 * @see IDebugEventSetListener#handleDebugEvents(DebugEvent[])
 	 */
 	@Override
 	public void handleDebugEvents(DebugEvent[] events) {
 		for (int i = 0; i < events.length; i++) {
 			DebugEvent event = events[i];
 			if (event.getSource() instanceof IDebugTarget && event.getKind() == DebugEvent.TERMINATE) {
 				cleanup((IDebugTarget)event.getSource());
 			}
 		}
 	}

 	/**
 	 * Returns the debug target associated with the given
 	 * scrapbook page, or <code>null</code> if none.
 	 *
 	 * @param page file representing scrapbook page
 	 * @return associated debug target or <code>null</code>
 	 */
 	public IDebugTarget getDebugTarget(IFile page) {
 		return fScrapbookToVMs.get(page);
 	}

 	/**
 	 * Returns the magic breakpoint associated with the given
 	 * scrapbook VM. The magic breakpoint is the location at
 	 * which an evaluation begins.
 	 *
 	 * @param target a scrapbook debug target
 	 * @return the breakpoint at which an evaluation begins
 	 *  or <code>null</code> if none
 	 */
 	public IBreakpoint getMagicBreakpoint(IDebugTarget target) {
 		return fVMsToBreakpoints.get(target);
 	}

 	protected void showNoPageDialog() {
 		String title= SnippetMessages.getString("ScrapbookLauncher.error.title"); //$NON-NLS-1$
 		String msg= SnippetMessages.getString("ScrapbookLauncher.error.pagenotfound"); //$NON-NLS-1$
 		MessageDialog.openError(JDIDebugUIPlugin.getActiveWorkbenchShell(),title, msg);
 	}

 	protected void cleanup(IDebugTarget target) {
 		Object page = fVMsToScrapbooks.get(target);
 		if (page != null) {
 			fVMsToScrapbooks.remove(target);
 			fScrapbookToVMs.remove(page);
 			fVMsToBreakpoints.remove(target);
 			ILaunch launch = target.getLaunch();
 			if (launch != null) {
 				getLaunchManager().removeLaunch(launch);
 			}
 			if (fVMsToScrapbooks.isEmpty()) {
 				// no need to listen to events if no scrap books running
 				DebugPlugin.getDefault().removeDebugEventListener(this);
 			}
 		}
 	}

 	protected URL getEncodedURL(File file) throws MalformedURLException, UnsupportedEncodingException {
 		//looking at File.toURL the delimiter is always '/'
 		// NOT File.separatorChar
 		String urlDelimiter= "/"; //$NON-NLS-1$
 		String unencoded= file.toURL().toExternalForm();
 		StringBuffer encoded= new StringBuffer();
 		StringTokenizer tokenizer= new StringTokenizer(unencoded, urlDelimiter);

 		encoded.append(tokenizer.nextToken()); //file:
 		encoded.append(urlDelimiter);
 		encoded.append(tokenizer.nextToken()); //drive letter and ':'
 		while (tokenizer.hasMoreElements()) {
 			encoded.append(urlDelimiter);
 			String token= tokenizer.nextToken();
 			try {
 				encoded.append(URLEncoder.encode(token, ResourcesPlugin.getEncoding()));
 			} catch (UnsupportedEncodingException e) {
 				encoded.append(URLEncoder.encode(token, "UTF-8")); //$NON-NLS-1$
 			}
 		}
 		if (file.isDirectory()) {
 			encoded.append(urlDelimiter);
 		}
 		return new URL(encoded.toString());
 	}

 	/**
 	 * Returns the launch configuration used as a template for launching the
 	 * given scrapbook file, or <code>null</code> if none. The template contains
 	 * working directory and JRE settings to use when launching the scrapbook.
 	 * @param file the backing config file
 	 * @return the launch configuration template
 	 * @throws CoreException if an exception occurs
 	 */
 	public static ILaunchConfiguration getLaunchConfigurationTemplate(IFile file) throws CoreException {
 		String memento = getLaunchConfigMemento(file);
 		if (memento != null) {
 			return getLaunchManager().getLaunchConfiguration(memento);
 		}
 		return null;
 	}

 	/**
 	 * Creates and saves template launch configuration for the given scrapbook file.
 	 * @param page the backing page
 	 * @return the new {@link ILaunchConfiguration} template
 	 * @throws CoreException if an exception occurs
 	 */
 	public static ILaunchConfiguration createLaunchConfigurationTemplate(IFile page) throws CoreException {
 		ILaunchConfigurationType lcType = getLaunchManager().getLaunchConfigurationType(IJavaLaunchConfigurationConstants.ID_JAVA_APPLICATION);
 		String name = NLS.bind(SnippetMessages.getString("ScrapbookLauncher.17"), new String[]{page.getName()}); //$NON-NLS-1$
 		ILaunchConfigurationWorkingCopy wc = lcType.newInstance(null, name);
 		wc.setAttribute(IDebugUIConstants.ATTR_PRIVATE, true);
 		wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_MAIN_TYPE_NAME, "org.eclipse.jdt.internal.debug.ui.snippeteditor.ScrapbookMain"); //$NON-NLS-1$
 		wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROJECT_NAME, page.getProject().getName());
 		wc.setAttribute(SCRAPBOOK_LAUNCH, SCRAPBOOK_LAUNCH);
 		wc.setAttribute(SCRAPBOOK_FILE_PATH, page.getFullPath().toString());
 		wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_SOURCE_PATH_PROVIDER, "org.eclipse.jdt.debug.ui.scrapbookSourcepathProvider"); //$NON-NLS-1$
 		JavaMigrationDelegate.updateResourceMapping(wc);
 		ILaunchConfiguration config = wc.doSave();
 		setLaunchConfigMemento(page, config.getMemento());
 		return config;
 	}

 	/**
 	 * Returns the handle memento for the given scrapbook's launch configuration
 	 * template, or <code>null</code> if none.
 	 * @param file the launch configuration template
 	 * @return the {@link String} memento
 	 */
 	private static String getLaunchConfigMemento(IFile file) {
 		try {
 			return file.getPersistentProperty(SNIPPET_EDITOR_LAUNCH_CONFIG_HANDLE_MEMENTO);
 		} catch (CoreException e) {
 			JDIDebugUIPlugin.log(e);
 		}
 		return null;
 	}

 	/**
 	 * Sets the handle memento for the given scrapbook's launch configuration
 	 * template.
 	 * @param file the backing file
 	 * @param memento the {@link String} memento
 	 */
 	protected static void setLaunchConfigMemento(IFile file, String memento) {
 		try {
 			file.setPersistentProperty(SNIPPET_EDITOR_LAUNCH_CONFIG_HANDLE_MEMENTO, memento);
 		} catch (CoreException e) {
 			JDIDebugUIPlugin.log(e);
 		}
 	}

 	/**
 	 * Returns the launch manager.
 	 * @return the launch manager instance
 	 */
 	protected static ILaunchManager getLaunchManager() {
 		return DebugPlugin.getDefault().getLaunchManager();
 	}

 	/**
 	 * Returns the working directory attribute for the given snippet file,
 	 * possibly <code>null</code>.
 	 * @param file the backing file
 	 * @return the working directory
 	 *
 	 * @exception CoreException if unable to retrieve the attribute
 	 */
 	public static String getWorkingDirectoryAttribute(IFile file) throws CoreException {
 		ILaunchConfiguration config = getLaunchConfigurationTemplate(file);
 		if (config != null) {
 			return config.getAttribute(IJavaLaunchConfigurationConstants.ATTR_WORKING_DIRECTORY, (String)null);
 		}
 		return null;
 	}

 	/**
 	 * Returns the VM arguments attribute for the given snippet file,
 	 * possibly <code>null</code>.
 	 * @param file the backing file
 	 * @return the VM arguments
 	 *
 	 * @exception CoreException if unable to retrieve the attribute
 	 */
 	public static String getVMArgsAttribute(IFile file) throws CoreException {
 		ILaunchConfiguration config = getLaunchConfigurationTemplate(file);
 		if (config != null) {
 			return config.getAttribute(IJavaLaunchConfigurationConstants.ATTR_VM_ARGUMENTS, (String)null);
 		}
 		return null;
 	}

 	/**
 	 * Returns the VM install used to launch the given snippet file.
 	 * @param file the backing file
 	 * @return the VM install
 	 *
 	 * @exception CoreException if unable to retrieve the attribute
 	 */
 	public static IVMInstall getVMInstall(IFile file) throws CoreException {
 		ILaunchConfiguration config = getLaunchConfigurationTemplate(file);
 		if (config == null) {
 			IJavaProject pro = JavaCore.create(file.getProject());
 			return JavaRuntime.getVMInstall(pro);
 		}
 		return JavaRuntime.computeVMInstall(config);
 	}

 	/**
 	 * Deletes any scrapbook launch configurations for scrap books that
 	 * have been deleted. Rather than listening to all resource deltas,
 	 * configurations are deleted each time a scrapbook is launched - which is
 	 * infrequent.
 	 */
 	public void cleanupLaunchConfigurations() {
 		try {
 			ILaunchConfigurationType lcType = getLaunchManager().getLaunchConfigurationType(IJavaLaunchConfigurationConstants.ID_JAVA_APPLICATION);
 			ILaunchConfiguration[] configs = getLaunchManager().getLaunchConfigurations(lcType);
 			IWorkspaceRoot root = ResourcesPlugin.getWorkspace().getRoot();
 			for (int i = 0; i < configs.length; i++) {
 				String path = configs[i].getAttribute(SCRAPBOOK_FILE_PATH, (String)null);
 				if (path != null) {
 					IPath pagePath = new Path(path);
 					IResource res = root.findMember(pagePath);
 					if (res == null) {
 						// config without a page - delete it
 						configs[i].delete();
 					}
 				}
 			}
 		} catch (CoreException e) {
 			// log quietly
 			JDIDebugUIPlugin.log(e);
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2015 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.jdt.internal.debug.ui.snippeteditor;


	import java.io.File;
	import java.io.IOException;
	import java.io.UnsupportedEncodingException;
	import java.net.MalformedURLException;
	import java.net.URL;
	import java.net.URLEncoder;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.List;
	import java.util.StringTokenizer;

	import org.eclipse.core.resources.IFile;
	import org.eclipse.core.resources.IResource;
	import org.eclipse.core.resources.IWorkspaceRoot;
	import org.eclipse.core.resources.ResourcesPlugin;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.FileLocator;
	import org.eclipse.core.runtime.IPath;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Path;
	import org.eclipse.core.runtime.QualifiedName;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.debug.core.DebugEvent;
	import org.eclipse.debug.core.DebugPlugin;
	import org.eclipse.debug.core.IDebugEventSetListener;
	import org.eclipse.debug.core.ILaunch;
	import org.eclipse.debug.core.ILaunchConfiguration;
	import org.eclipse.debug.core.ILaunchConfigurationType;
	import org.eclipse.debug.core.ILaunchConfigurationWorkingCopy;
	import org.eclipse.debug.core.ILaunchManager;
	import org.eclipse.debug.core.model.IBreakpoint;
	import org.eclipse.debug.core.model.IDebugTarget;
	import org.eclipse.debug.ui.IDebugUIConstants;
	import org.eclipse.jdt.core.IJavaProject;
	import org.eclipse.jdt.core.JavaCore;
	import org.eclipse.jdt.core.ToolFactory;
	import org.eclipse.jdt.core.compiler.CharOperation;
	import org.eclipse.jdt.core.util.IClassFileReader;
	import org.eclipse.jdt.core.util.ICodeAttribute;
	import org.eclipse.jdt.core.util.ILineNumberAttribute;
	import org.eclipse.jdt.core.util.IMethodInfo;
	import org.eclipse.jdt.debug.core.IJavaLineBreakpoint;
	import org.eclipse.jdt.debug.core.JDIDebugModel;
	import org.eclipse.jdt.debug.ui.IJavaDebugUIConstants;
	import org.eclipse.jdt.internal.debug.ui.JDIDebugUIPlugin;
	import org.eclipse.jdt.internal.launching.JavaMigrationDelegate;
	import org.eclipse.jdt.launching.IJavaLaunchConfigurationConstants;
	import org.eclipse.jdt.launching.IRuntimeClasspathEntry;
	import org.eclipse.jdt.launching.IVMInstall;
	import org.eclipse.jdt.launching.JavaRuntime;
	import org.eclipse.jface.dialogs.MessageDialog;
	import org.eclipse.osgi.util.NLS;

	/**
	* Support for launching scrapbook using launch configurations.
	*/

	public class ScrapbookLauncher implements IDebugEventSetListener {

	public static final String SCRAPBOOK_LAUNCH = IJavaDebugUIConstants.PLUGIN_ID + ".scrapbook_launch"; //$NON-NLS-1$

	public static final String SCRAPBOOK_FILE_PATH = IJavaDebugUIConstants.PLUGIN_ID + ".scrapbook_file_path"; //$NON-NLS-1$

	/**
	* Persistent property associated with snippet files specifying working directory.
	* Same format as the associated launch configuration attribute
	* <code>ATTR_WORKING_DIR</code>.
	*/
	public static final QualifiedName SNIPPET_EDITOR_LAUNCH_CONFIG_HANDLE_MEMENTO = new QualifiedName(IJavaDebugUIConstants.PLUGIN_ID, "snippet_editor_launch_config"); //$NON-NLS-1$

	private IJavaLineBreakpoint fMagicBreakpoint;

	private HashMap<IFile, IDebugTarget> fScrapbookToVMs = new HashMap<>(10);
	private HashMap<IDebugTarget, IBreakpoint> fVMsToBreakpoints = new HashMap<>(10);
	private HashMap<IDebugTarget, IFile> fVMsToScrapbooks = new HashMap<>(10);

	private static ScrapbookLauncher fgDefault = null;

	private ScrapbookLauncher() {
	//see getDefault()
	}

	public static ScrapbookLauncher getDefault() {
	if (fgDefault == null) {
	fgDefault = new ScrapbookLauncher();
	}
	return fgDefault;
	}

	/**
	* Launches a VM for the given scrapbook page, in debug mode.
	* Returns an existing launch if the page is already running.
	* @param page the scrapbook page file
	*
	* @return resulting launch, or <code>null</code> on failure
	*/
	protected ILaunch launch(IFile page) {

	// clean up orphaned launch configurations
	cleanupLaunchConfigurations();

	if (!page.getFileExtension().equals("jpage")) { //$NON-NLS-1$
	showNoPageDialog();
	return null;
	}

	IDebugTarget vm = getDebugTarget(page);
	if (vm != null) {
	//already launched
	return vm.getLaunch();
	}

	IJavaProject javaProject= JavaCore.create(page.getProject());

	URL jarURL = null;
	try {
	jarURL = JDIDebugUIPlugin.getDefault().getBundle().getEntry("snippetsupport.jar"); //$NON-NLS-1$
	jarURL = FileLocator.toFileURL(jarURL);
	} catch (MalformedURLException e) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
	return null;
	} catch (IOException e) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
	return null;
	}

	List<IRuntimeClasspathEntry> cp = new ArrayList<>(3);
	String jarFile = jarURL.getFile();
	IRuntimeClasspathEntry supportEntry = JavaRuntime.newArchiveRuntimeClasspathEntry(new Path(jarFile));
	cp.add(supportEntry);
	// get bootpath entries
	try {
	IRuntimeClasspathEntry[] entries = JavaRuntime.computeUnresolvedRuntimeClasspath(javaProject);
	for (int i = 0; i < entries.length; i++) {
	if (entries[i].getClasspathProperty() != IRuntimeClasspathEntry.USER_CLASSES) {
	cp.add(entries[i]);
	}
	}
	IRuntimeClasspathEntry[] classPath = cp.toArray(new IRuntimeClasspathEntry[cp.size()]);

	return doLaunch(javaProject, page, classPath, jarFile);
	} catch (CoreException e) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
	}
	return null;
	}

	private ILaunch doLaunch(IJavaProject p, IFile page, IRuntimeClasspathEntry[] classPath, String jarFile) {
	try {
	if (fVMsToScrapbooks.isEmpty()) {
	// register for debug events if a scrapbook is not currently running
	DebugPlugin.getDefault().addDebugEventListener(this);
	}
	ILaunchConfiguration config = null;
	ILaunchConfigurationWorkingCopy wc = null;
	try {
	config = getLaunchConfigurationTemplate(page);
	if (config != null) {
	wc = config.getWorkingCopy();
	}
	} catch (CoreException e) {
	config = null;
	JDIDebugUIPlugin.errorDialog("Unable to retrieve scrapbook settings", e); //$NON-NLS-1$
	}

	if (config == null) {
	config = createLaunchConfigurationTemplate(page);
	wc = config.getWorkingCopy();
	}

	IPath outputLocation = p.getProject().getWorkingLocation(JDIDebugUIPlugin.getUniqueIdentifier());
	File f = outputLocation.toFile();
	URL u = null;
	try {
	u = getEncodedURL(f);
	} catch (MalformedURLException e) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
	return null;
	}
	catch(UnsupportedEncodingException usee) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", usee); //$NON-NLS-1$
	return null;
	}
	String[] defaultClasspath = JavaRuntime.computeDefaultRuntimeClassPath(p);
	String[] urls = new String[defaultClasspath.length + 1];
	urls[0] = u.toExternalForm();
	for (int i = 0; i < defaultClasspath.length; i++) {
	f = new File(defaultClasspath[i]);
	try {
	urls[i + 1] = getEncodedURL(f).toExternalForm();
	} catch (MalformedURLException e) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
	return null;
	}
	catch(UnsupportedEncodingException usee) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", usee); //$NON-NLS-1$
	return null;
	}
	}

	// convert to mementos
	List<String> classpathList= new ArrayList<>(classPath.length);
	for (int i = 0; i < classPath.length; i++) {
	classpathList.add(classPath[i].getMemento());
	}
	if(wc == null) {
	wc = config.getWorkingCopy();
	}
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_DEFAULT_CLASSPATH, false);
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_CLASSPATH, classpathList);
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROJECT_NAME, p.getElementName());
	if (wc.getAttribute(IJavaLaunchConfigurationConstants.ATTR_SOURCE_PATH_PROVIDER, (String)null) == null) {
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_SOURCE_PATH_PROVIDER, "org.eclipse.jdt.debug.ui.scrapbookSourcepathProvider"); //$NON-NLS-1$
	}

	StringBuffer urlsString = new StringBuffer();
	for (int i = 0; i < urls.length; i++) {
	urlsString.append(' ');
	urlsString.append(urls[i]);
	}
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROGRAM_ARGUMENTS, urlsString.toString());
	wc.setAttribute(SCRAPBOOK_LAUNCH, SCRAPBOOK_LAUNCH);

	config = wc.doSave();

	ILaunch launch = config.launch(ILaunchManager.DEBUG_MODE, null);
	if (launch != null) {
	IDebugTarget dt = launch.getDebugTarget();
	IBreakpoint magicBreakpoint = createMagicBreakpoint(jarFile);
	fScrapbookToVMs.put(page, dt);
	fVMsToScrapbooks.put(dt, page);
	fVMsToBreakpoints.put(dt, magicBreakpoint);
	dt.breakpointAdded(magicBreakpoint);
	launch.setAttribute(SCRAPBOOK_LAUNCH, SCRAPBOOK_LAUNCH);
	return launch;
	}
	} catch (CoreException e) {
	JDIDebugUIPlugin.errorDialog("Unable to launch scrapbook VM", e); //$NON-NLS-1$
	}
	return null;
	}

	/**
	* Creates an "invisible" line breakpoint.
	*
	* @param jarFile
	* path to the snippetsupport.jar file
	* @return the new 'magic' breakpoint
	* @throws CoreException
	* if an exception occurs
	*/
	IBreakpoint createMagicBreakpoint(String jarFile) throws CoreException {
	// set a breakpoint on the "Thread.sleep(100);" line of the "ScrapbookMainnop()" method
	String typeName = "org.eclipse.jdt.internal.debug.ui.snippeteditor.ScrapbookMain"; //$NON-NLS-1$

	IClassFileReader reader = ToolFactory.createDefaultClassFileReader(jarFile, typeName.replace('.', '/')
	+ ".class", IClassFileReader.METHOD_INFOS \| IClassFileReader.METHOD_BODIES); //$NON-NLS-1$
	IMethodInfo[] methodInfos = reader.getMethodInfos();
	for (IMethodInfo methodInfo : methodInfos) {
	if (!CharOperation.equals("nop".toCharArray(), methodInfo.getName())) {//$NON-NLS-1$
	continue;
	}
	ICodeAttribute codeAttribute = methodInfo.getCodeAttribute();
	ILineNumberAttribute lineNumberAttribute = codeAttribute.getLineNumberAttribute();
	int[][] lineNumberTable = lineNumberAttribute.getLineNumberTable();
	int lineNumber = lineNumberTable[0][1];

	fMagicBreakpoint = JDIDebugModel.createLineBreakpoint(ResourcesPlugin.getWorkspace().getRoot(), typeName, lineNumber, -1, -1, 0, false, null);
	fMagicBreakpoint.setPersisted(false);
	return fMagicBreakpoint;
	}
	throw new CoreException(new Status(IStatus.ERROR, JDIDebugUIPlugin.getUniqueIdentifier(), IJavaDebugUIConstants.INTERNAL_ERROR, "An error occurred creating the evaluation breakpoint location.", null)); //$NON-NLS-1$
	}

	/**
	* @see IDebugEventSetListener#handleDebugEvents(DebugEvent[])
	*/
	@Override
	public void handleDebugEvents(DebugEvent[] events) {
	for (int i = 0; i < events.length; i++) {
	DebugEvent event = events[i];
	if (event.getSource() instanceof IDebugTarget && event.getKind() == DebugEvent.TERMINATE) {
	cleanup((IDebugTarget)event.getSource());
	}
	}
	}

	/**
	* Returns the debug target associated with the given
	* scrapbook page, or <code>null</code> if none.
	*
	* @param page file representing scrapbook page
	* @return associated debug target or <code>null</code>
	*/
	public IDebugTarget getDebugTarget(IFile page) {
	return fScrapbookToVMs.get(page);
	}

	/**
	* Returns the magic breakpoint associated with the given
	* scrapbook VM. The magic breakpoint is the location at
	* which an evaluation begins.
	*
	* @param target a scrapbook debug target
	* @return the breakpoint at which an evaluation begins
	* or <code>null</code> if none
	*/
	public IBreakpoint getMagicBreakpoint(IDebugTarget target) {
	return fVMsToBreakpoints.get(target);
	}

	protected void showNoPageDialog() {
	String title= SnippetMessages.getString("ScrapbookLauncher.error.title"); //$NON-NLS-1$
	String msg= SnippetMessages.getString("ScrapbookLauncher.error.pagenotfound"); //$NON-NLS-1$
	MessageDialog.openError(JDIDebugUIPlugin.getActiveWorkbenchShell(),title, msg);
	}

	protected void cleanup(IDebugTarget target) {
	Object page = fVMsToScrapbooks.get(target);
	if (page != null) {
	fVMsToScrapbooks.remove(target);
	fScrapbookToVMs.remove(page);
	fVMsToBreakpoints.remove(target);
	ILaunch launch = target.getLaunch();
	if (launch != null) {
	getLaunchManager().removeLaunch(launch);
	}
	if (fVMsToScrapbooks.isEmpty()) {
	// no need to listen to events if no scrap books running
	DebugPlugin.getDefault().removeDebugEventListener(this);
	}
	}
	}

	protected URL getEncodedURL(File file) throws MalformedURLException, UnsupportedEncodingException {
	//looking at File.toURL the delimiter is always '/'
	// NOT File.separatorChar
	String urlDelimiter= "/"; //$NON-NLS-1$
	String unencoded= file.toURL().toExternalForm();
	StringBuffer encoded= new StringBuffer();
	StringTokenizer tokenizer= new StringTokenizer(unencoded, urlDelimiter);

	encoded.append(tokenizer.nextToken()); //file:
	encoded.append(urlDelimiter);
	encoded.append(tokenizer.nextToken()); //drive letter and ':'
	while (tokenizer.hasMoreElements()) {
	encoded.append(urlDelimiter);
	String token= tokenizer.nextToken();
	try {
	encoded.append(URLEncoder.encode(token, ResourcesPlugin.getEncoding()));
	} catch (UnsupportedEncodingException e) {
	encoded.append(URLEncoder.encode(token, "UTF-8")); //$NON-NLS-1$
	}
	}
	if (file.isDirectory()) {
	encoded.append(urlDelimiter);
	}
	return new URL(encoded.toString());
	}

	/**
	* Returns the launch configuration used as a template for launching the
	* given scrapbook file, or <code>null</code> if none. The template contains
	* working directory and JRE settings to use when launching the scrapbook.
	* @param file the backing config file
	* @return the launch configuration template
	* @throws CoreException if an exception occurs
	*/
	public static ILaunchConfiguration getLaunchConfigurationTemplate(IFile file) throws CoreException {
	String memento = getLaunchConfigMemento(file);
	if (memento != null) {
	return getLaunchManager().getLaunchConfiguration(memento);
	}
	return null;
	}

	/**
	* Creates and saves template launch configuration for the given scrapbook file.
	* @param page the backing page
	* @return the new {@link ILaunchConfiguration} template
	* @throws CoreException if an exception occurs
	*/
	public static ILaunchConfiguration createLaunchConfigurationTemplate(IFile page) throws CoreException {
	ILaunchConfigurationType lcType = getLaunchManager().getLaunchConfigurationType(IJavaLaunchConfigurationConstants.ID_JAVA_APPLICATION);
	String name = NLS.bind(SnippetMessages.getString("ScrapbookLauncher.17"), new String[]{page.getName()}); //$NON-NLS-1$
	ILaunchConfigurationWorkingCopy wc = lcType.newInstance(null, name);
	wc.setAttribute(IDebugUIConstants.ATTR_PRIVATE, true);
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_MAIN_TYPE_NAME, "org.eclipse.jdt.internal.debug.ui.snippeteditor.ScrapbookMain"); //$NON-NLS-1$
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROJECT_NAME, page.getProject().getName());
	wc.setAttribute(SCRAPBOOK_LAUNCH, SCRAPBOOK_LAUNCH);
	wc.setAttribute(SCRAPBOOK_FILE_PATH, page.getFullPath().toString());
	wc.setAttribute(IJavaLaunchConfigurationConstants.ATTR_SOURCE_PATH_PROVIDER, "org.eclipse.jdt.debug.ui.scrapbookSourcepathProvider"); //$NON-NLS-1$
	JavaMigrationDelegate.updateResourceMapping(wc);
	ILaunchConfiguration config = wc.doSave();
	setLaunchConfigMemento(page, config.getMemento());
	return config;
	}

	/**
	* Returns the handle memento for the given scrapbook's launch configuration
	* template, or <code>null</code> if none.
	* @param file the launch configuration template
	* @return the {@link String} memento
	*/
	private static String getLaunchConfigMemento(IFile file) {
	try {
	return file.getPersistentProperty(SNIPPET_EDITOR_LAUNCH_CONFIG_HANDLE_MEMENTO);
	} catch (CoreException e) {
	JDIDebugUIPlugin.log(e);
	}
	return null;
	}

	/**
	* Sets the handle memento for the given scrapbook's launch configuration
	* template.
	* @param file the backing file
	* @param memento the {@link String} memento
	*/
	protected static void setLaunchConfigMemento(IFile file, String memento) {
	try {
	file.setPersistentProperty(SNIPPET_EDITOR_LAUNCH_CONFIG_HANDLE_MEMENTO, memento);
	} catch (CoreException e) {
	JDIDebugUIPlugin.log(e);
	}
	}

	/**
	* Returns the launch manager.
	* @return the launch manager instance
	*/
	protected static ILaunchManager getLaunchManager() {
	return DebugPlugin.getDefault().getLaunchManager();
	}

	/**
	* Returns the working directory attribute for the given snippet file,
	* possibly <code>null</code>.
	* @param file the backing file
	* @return the working directory
	*
	* @exception CoreException if unable to retrieve the attribute
	*/
	public static String getWorkingDirectoryAttribute(IFile file) throws CoreException {
	ILaunchConfiguration config = getLaunchConfigurationTemplate(file);
	if (config != null) {
	return config.getAttribute(IJavaLaunchConfigurationConstants.ATTR_WORKING_DIRECTORY, (String)null);
	}
	return null;
	}

	/**
	* Returns the VM arguments attribute for the given snippet file,
	* possibly <code>null</code>.
	* @param file the backing file
	* @return the VM arguments
	*
	* @exception CoreException if unable to retrieve the attribute
	*/
	public static String getVMArgsAttribute(IFile file) throws CoreException {
	ILaunchConfiguration config = getLaunchConfigurationTemplate(file);
	if (config != null) {
	return config.getAttribute(IJavaLaunchConfigurationConstants.ATTR_VM_ARGUMENTS, (String)null);
	}
	return null;
	}

	/**
	* Returns the VM install used to launch the given snippet file.
	* @param file the backing file
	* @return the VM install
	*
	* @exception CoreException if unable to retrieve the attribute
	*/
	public static IVMInstall getVMInstall(IFile file) throws CoreException {
	ILaunchConfiguration config = getLaunchConfigurationTemplate(file);
	if (config == null) {
	IJavaProject pro = JavaCore.create(file.getProject());
	return JavaRuntime.getVMInstall(pro);
	}
	return JavaRuntime.computeVMInstall(config);
	}

	/**
	* Deletes any scrapbook launch configurations for scrap books that
	* have been deleted. Rather than listening to all resource deltas,
	* configurations are deleted each time a scrapbook is launched - which is
	* infrequent.
	*/
	public void cleanupLaunchConfigurations() {
	try {
	ILaunchConfigurationType lcType = getLaunchManager().getLaunchConfigurationType(IJavaLaunchConfigurationConstants.ID_JAVA_APPLICATION);
	ILaunchConfiguration[] configs = getLaunchManager().getLaunchConfigurations(lcType);
	IWorkspaceRoot root = ResourcesPlugin.getWorkspace().getRoot();
	for (int i = 0; i < configs.length; i++) {
	String path = configs[i].getAttribute(SCRAPBOOK_FILE_PATH, (String)null);
	if (path != null) {
	IPath pagePath = new Path(path);
	IResource res = root.findMember(pagePath);
	if (res == null) {
	// config without a page - delete it
	configs[i].delete();
	}
	}
	}
	} catch (CoreException e) {
	// log quietly
	JDIDebugUIPlugin.log(e);
	}
	}
	}