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The source code

/*
 *                 Sun Public License Notice
 *
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 *
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2004 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.apache.tools.ant.module.bridge;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.lang.ref.Reference;
import java.lang.ref.SoftReference;
import java.net.URL;
import java.net.URLClassLoader;
import java.security.AllPermission;
import java.security.CodeSource;
import java.security.PermissionCollection;
import java.security.Permissions;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.StringTokenizer;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import org.apache.tools.ant.module.AntModule;
import org.apache.tools.ant.module.AntSettings;
import org.openide.ErrorManager;
import org.openide.execution.NbClassPath;
import org.openide.modules.InstalledFileLocator;
import org.openide.modules.ModuleInfo;
import org.openide.util.Lookup;
import org.openide.util.LookupEvent;
import org.openide.util.LookupListener;
import org.openide.util.io.NullOutputStream;
import org.openide.xml.XMLUtil;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * Utility class providing entry points to the bridging functionality.
 * @author Jesse Glick
 */
public final class AntBridge {
    
    private static final ErrorManager err = ErrorManager.getDefault().getInstance(AntBridge.class.getName());
    
    private AntBridge() {}
    
    private static final String KEY_MAIN_CLASS_PATH = "mainClassPath"; // NOI18N
    private static final String KEY_MAIN_CLASS_LOADER = "mainClassLoader"; // NOI18N
    private static final String KEY_BRIDGE_CLASS_LOADER = "bridgeClassLoader"; // NOI18N
    private static final String KEY_BRIDGE = "bridge"; // NOI18N
    private static final String KEY_CUSTOM_DEFS = "customDefs"; // NOI18N
    private static final String KEY_CUSTOM_DEF_CLASS_LOADERS = "customDefClassLoaders"; // NOI18N
    private static Reference stuff = null; // Reference
    
    private static List listeners = new ArrayList(); // List
    
    private static final class MiscListener implements PropertyChangeListener, LookupListener {
        MiscListener() {}
        private ModuleInfo[] modules = null;
        public void propertyChange(PropertyChangeEvent ev) {
            String prop = ev.getPropertyName();
            if (AntSettings.PROP_ANT_HOME.equals(prop) ||
                    AntSettings.PROP_EXTRA_CLASSPATH.equals(prop)) {
                err.log("AntBridge got settings change in " + prop);
                fireChange();
            } else if (ModuleInfo.PROP_ENABLED.equals(prop)) {
                err.log("AntBridge got module enablement change on " + ev.getSource());
                fireChange();
            }
        }
        public void resultChanged(LookupEvent ev) {
            err.log("AntModule got ModuleInfo change");
            synchronized (this) {
                if (modules != null) {
                    for (int i = 0; i < modules.length; i++) {
                        modules[i].removePropertyChangeListener(this);
                    }
                    modules = null;
                }
            }
            fireChange();
        }
        public synchronized ModuleInfo[] getEnabledModules() {
            if (modules == null) {
                Collection c = modulesResult.allInstances();
                modules = (ModuleInfo[])c.toArray(new ModuleInfo[c.size()]);
                for (int i = 0; i < modules.length; i++) {
                    modules[i].addPropertyChangeListener(this);
                }
            }
            List/**/ enabledModules = new ArrayList(modules.length);
            for (int i = 0; i < modules.length; i++) {
                if (modules[i].isEnabled()) {
                    enabledModules.add(modules[i]);
                }
            }
            return (ModuleInfo[])enabledModules.toArray(new ModuleInfo[enabledModules.size()]);
        }
    }
    private static MiscListener miscListener = new MiscListener();
    private static Lookup.Result modulesResult = Lookup.getDefault().lookup(new Lookup.Template(ModuleInfo.class));
    static {
        AntSettings.getDefault().addPropertyChangeListener(miscListener);
        modulesResult.addLookupListener(miscListener);
    }
    
    /**
     * Listen for changes in the contents of the bridge, as e.g. after changing the
     * location of the installed copy of Ant.
     */
    public static synchronized void addChangeListener(ChangeListener l) {
        listeners.add(l);
    }
    
    /**
     * Stop listening for changes in the contents of the bridge.
     */
    public static synchronized void removeChangeListener(ChangeListener l) {
        listeners.remove(l);
    }
    
    private static void fireChange() {
        stuff = null;
        ChangeEvent ev = new ChangeEvent(AntBridge.class);
        ChangeListener[] ls;
        synchronized (AntBridge.class) {
            ls = (ChangeListener[])listeners.toArray(new ChangeListener[listeners.size()]);
        }
        for (int i = 0; i < ls.length; i++) {
            ls[i].stateChanged(ev);
        }
    }
    
    /**
     * Get the loader responsible for loading Ant together with any
     * user-defined classpath.
     */
    public static ClassLoader getMainClassLoader() {
        return (ClassLoader)getStuff().get(KEY_MAIN_CLASS_LOADER);
    }
    
    /**
     * Get the loader which contains the bridge code.
     */
    private static ClassLoader getBridgeClassLoader() {
        return (ClassLoader)getStuff().get(KEY_BRIDGE_CLASS_LOADER);
    }
    
    /**
     * Get any custom task/type definitions stored in $nbhome/ant/nblib/*.jar.
     * Some of the classes might not be fully resolvable, so beware.
     * The names will include namespace prefixes.
     * 

* Only minimal antlib syntax is currently interpreted here: * only <taskdef> and <typedef>, * and only the name and classname attributes. */ public static Map/*>*/ getCustomDefsWithNamespace() { return (Map)getStuff().get(KEY_CUSTOM_DEFS); } /** * Same as {@link #getCustomDefsWithNamespace} but without any namespace prefixes. */ public static Map/*>*/ getCustomDefsNoNamespace() { Map/*>*/ m = new HashMap(); Iterator it = getCustomDefsWithNamespace().entrySet().iterator(); while (it.hasNext()) { Map.Entry entry = (Map.Entry)it.next(); String type = (String)entry.getKey(); Map defs = (Map)entry.getValue(); Map/*Map*/ m2 = new HashMap(); Iterator it2 = defs.entrySet().iterator(); while (it2.hasNext()) { Map.Entry entry2 = (Map.Entry)it2.next(); String fqn = (String)entry2.getKey(); Class clazz = (Class)entry2.getValue(); String name; int idx = fqn.lastIndexOf(':'); if (idx != -1) { name = fqn.substring(idx + 1); } else { name = fqn; } m2.put(name, clazz); } m.put(type, m2); } return m; } /** * Get a map from enabled module code name bases to class loaders containing * JARs from ant/nblib/*.jar. */ public static Map/**/ getCustomDefClassLoaders() throws IOException { return (Map)getStuff().get(KEY_CUSTOM_DEF_CLASS_LOADERS); } /** * Get the bridge interface. */ public static BridgeInterface getInterface() { return (BridgeInterface)getStuff().get(KEY_BRIDGE); } private synchronized static Map getStuff() { Map m; if (stuff != null) { m = (Map)stuff.get(); } else { m = null; } if (m == null) { m = createStuff(); stuff = new SoftReference(m); } return m; } private static Map createStuff() { err.log("AntBridge.createStuff - loading Ant installation..."); Map m = new HashMap(); try { List/**/ mainClassPath = createMainClassPath(); err.log("mainClassPath=" + mainClassPath); m.put(KEY_MAIN_CLASS_PATH, classPathToString(mainClassPath)); ClassLoader main = createMainClassLoader(mainClassPath); m.put(KEY_MAIN_CLASS_LOADER, main); ClassLoader bridgeLoader = createBridgeClassLoader(main); m.put(KEY_BRIDGE_CLASS_LOADER, bridgeLoader); // Ensures that the loader is functional, and that it is at least 1.5.x // so that our classes can link against it successfully, and that // we are really loading Ant from the right place: Class ihClazz = Class.forName("org.apache.tools.ant.input.InputHandler", false, bridgeLoader); // NOI18N ClassLoader loaderUsedForAnt = ihClazz.getClassLoader(); if (loaderUsedForAnt != main) { throw new IllegalStateException("Wrong class loader is finding Ant: " + loaderUsedForAnt); // NOI18N } Class ihClazz2 = Class.forName("org.apache.tools.ant.input.InputHandler", false, main); // NOI18N if (ihClazz2 != ihClazz) { throw new IllegalStateException("Main and bridge class loaders do not agree on version of Ant: " + ihClazz2.getClassLoader()); // NOI18N } try { Class alClazz = Class.forName("org.apache.tools.ant.taskdefs.Antlib", false, bridgeLoader); // NOI18N if (alClazz.getClassLoader() != main) { throw new IllegalStateException("Bridge loader is loading stuff from elsewhere: " + alClazz.getClassLoader()); // NOI18N } Class alClazz2 = Class.forName("org.apache.tools.ant.taskdefs.Antlib", false, main); // NOI18N if (alClazz2 != alClazz) { throw new IllegalStateException("Main and bridge class loaders do not agree on version of Ant: " + alClazz2.getClassLoader()); // NOI18N } } catch (ClassNotFoundException cnfe) { // Fine, it was added in Ant 1.6. } Class impl = bridgeLoader.loadClass("org.apache.tools.ant.module.bridge.impl.BridgeImpl"); // NOI18N if (impl.getClassLoader() != bridgeLoader) { throw new IllegalStateException("Wrong class loader is finding bridge impl: " + impl.getClassLoader()); // NOI18N } m.put(KEY_BRIDGE, (BridgeInterface)impl.newInstance()); Map cDCLs = createCustomDefClassLoaders(main); m.put(KEY_CUSTOM_DEF_CLASS_LOADERS, cDCLs); m.put(KEY_CUSTOM_DEFS, createCustomDefs(cDCLs)); } catch (Exception e) { fallback(m, e); } catch (LinkageError e) { fallback(m, e); } return m; } private static void fallback(Map m, Throwable e) { m.clear(); ClassLoader dummy = ClassLoader.getSystemClassLoader(); m.put(KEY_MAIN_CLASS_LOADER, dummy); m.put(KEY_BRIDGE_CLASS_LOADER, dummy); m.put(KEY_BRIDGE, new DummyBridgeImpl(e)); Map defs = new HashMap(); defs.put("task", new HashMap()); // NOI18N defs.put("type", new HashMap()); // NOI18N m.put(KEY_CUSTOM_DEFS, defs); m.put(KEY_CUSTOM_DEF_CLASS_LOADERS, Collections.EMPTY_MAP); } private static final class JarFilter implements FilenameFilter { JarFilter() {} public boolean accept(File dir, String name) { return name.toLowerCase(Locale.US).endsWith(".jar"); // NOI18N } } private static String classPathToString(List/**/ cp) { StringBuffer b = new StringBuffer(); Iterator it = cp.iterator(); while (it.hasNext()) { b.append(((File) it.next()).getAbsolutePath()); if (it.hasNext()) { b.append(File.pathSeparator); } } return b.toString(); } private static String originalJavaClassPath = System.getProperty("java.class.path"); // NOI18N /** * Get the equivalent of java.class.path for the main Ant loader. * Includes everything in the main class loader, * plus the regular system class path (for tools.jar etc.). */ public static String getMainClassPath() { return (String) getStuff().get(KEY_MAIN_CLASS_PATH) + File.pathSeparatorChar + originalJavaClassPath; } private static List/**/ createMainClassPath() throws Exception { // Use LinkedHashSet to automatically suppress duplicates. Collection/**/ cp = new LinkedHashSet(); File libdir = new File(AntSettings.getDefault().getAntHomeWithDefault(), "lib"); // NOI18N if (!libdir.isDirectory()) throw new IOException("No such Ant library dir: " + libdir); // NOI18N err.log("Creating main class loader from " + libdir); File[] libs = libdir.listFiles(new JarFilter()); if (libs == null) throw new IOException("Listing: " + libdir); // NOI18N for (int i = 0; i < libs.length; i++) { cp.add(libs[i]); } NbClassPath extra = AntSettings.getDefault().getExtraClasspath(); String extrapath = extra.getClassPath(); if (extrapath.startsWith("\"") && extrapath.endsWith("\"")) { // NOI18N // *@%!* NbClassPath.getClassPath semantics. extrapath = extrapath.substring(1, extrapath.length() - 1); } StringTokenizer tok = new StringTokenizer(extrapath, File.pathSeparator); while (tok.hasMoreTokens()) { cp.add(new File(tok.nextToken())); } extra = AntSettings.getDefault().getAutomaticExtraClasspath(); extrapath = extra.getClassPath(); if (extrapath.startsWith("\"") && extrapath.endsWith("\"")) { // NOI18N extrapath = extrapath.substring(1, extrapath.length() - 1); } tok = new StringTokenizer(extrapath, File.pathSeparator); while (tok.hasMoreTokens()) { cp.add(new File(tok.nextToken())); } // XXX note that systemClassLoader will include boot.jar, and perhaps anything else // in lib/ext/*.jar, like rmi-ext.jar. Would be nicer to exclude everything NB-specific. // However the simplest way - to use the parent loader (JRE ext loader) - does not work // well because Ant assumes that tools.jar is in its classpath (for etc.). // Manually readding the JDK JARs would be possible, but then they would not be shared // with the versions used inside NB, which may cause inefficiencies or more memory usage. // On the other hand, if ant.jar is in ${java.class.path} (e.g. from a unit test), we // have to explicitly mask it out. What a mess... return new ArrayList(cp); } private static ClassLoader createMainClassLoader(List/**/ mainClassPath) throws Exception { URL[] cp = new URL[mainClassPath.size()]; Iterator it = mainClassPath.iterator(); int i = 0; while (it.hasNext()) { cp[i++] = ((File) it.next()).toURI().toURL(); } ClassLoader parent = ClassLoader.getSystemClassLoader(); if (err.isLoggable(ErrorManager.INFORMATIONAL)) { List/**/ parentURLs; if (parent instanceof URLClassLoader) { parentURLs = Arrays.asList(((URLClassLoader) parent).getURLs()); } else { parentURLs = null; } err.log("AntBridge.createMainClassLoader: cp=" + Arrays.asList(cp) + " parent.urls=" + parentURLs); } return new MaskedClassLoader(cp, parent); } private static ClassLoader createBridgeClassLoader(ClassLoader main) throws Exception { File bridgeJar = InstalledFileLocator.getDefault().locate("ant/nblib/bridge.jar", "org.apache.tools.ant.module", false); // NOI18N if (bridgeJar == null) { throw new IllegalStateException("no ant/nblib/bridge.jar found"); // NOI18N } return createAuxClassLoader(bridgeJar, main, AntBridge.class.getClassLoader()); } private static ClassLoader createAuxClassLoader(File lib, ClassLoader main, ClassLoader moduleLoader) throws IOException { return new AuxClassLoader(moduleLoader, main, lib.toURI().toURL()); } /** * Get a map from enabled module code name bases to class loaders containing * JARs from ant/nblib/*.jar. */ private static Map/**/ createCustomDefClassLoaders(ClassLoader main) throws IOException { Map/**/ m = new HashMap(); ModuleInfo[] modules = miscListener.getEnabledModules(); InstalledFileLocator ifl = InstalledFileLocator.getDefault(); for (int i = 0; i < modules.length; i++) { String cnb = modules[i].getCodeNameBase(); String cnbDashes = cnb.replace('.', '-'); File lib = ifl.locate("ant/nblib/" + cnbDashes + ".jar", cnb, false); // NOI18N if (lib == null) { continue; } ClassLoader l = createAuxClassLoader(lib, main, modules[i].getClassLoader()); m.put(cnb, l); } return m; } private static Map/*>*/ createCustomDefs(Map cDCLs) throws IOException { Map m = new HashMap(); Map tasks = new HashMap(); Map types = new HashMap(); // XXX #36776: should eventually support s here m.put("task", tasks); // NOI18N m.put("type", types); // NOI18N Iterator it = cDCLs.entrySet().iterator(); while (it.hasNext()) { Map.Entry entry = (Map.Entry)it.next(); String cnb = (String)entry.getKey(); ClassLoader l = (ClassLoader)entry.getValue(); String resource = cnb.replace('.', '/') + "/antlib.xml"; // NOI18N URL antlib = l.getResource(resource); if (antlib == null) { throw new IOException("Could not find " + resource + " in ant/nblib/" + cnb.replace('.', '-') + ".jar"); // NOI18N } Document doc; try { doc = XMLUtil.parse(new InputSource(antlib.toExternalForm()), false, true, /*XXX needed?*/null, null); } catch (SAXException e) { throw (IOException)new IOException(e.toString()).initCause(e); } Element docEl = doc.getDocumentElement(); if (!docEl.getLocalName().equals("antlib")) { // NOI18N throw new IOException("Bad root element for " + antlib + ": " + docEl); // NOI18N } NodeList nl = docEl.getChildNodes(); Properties newTaskDefs = new Properties(); Properties newTypeDefs = new Properties(); for (int i = 0; i < nl.getLength(); i++) { Node n = nl.item(i); if (n.getNodeType() != Node.ELEMENT_NODE) { continue; } Element def = (Element)n; boolean type; if (def.getNodeName().equals("taskdef")) { // NOI18N type = false; } else if (def.getNodeName().equals("typedef")) { // NOI18N type = true; } else { err.log(ErrorManager.WARNING, "Warning: unrecognized definition " + def + " in " + antlib); continue; } String name = def.getAttribute("name"); // NOI18N if (name == null) { // Not a hard error since there might be e.g. here // which we do not parse but which is permitted in antlib by Ant. err.log(ErrorManager.WARNING, "Warning: skipping definition " + def + " with no 'name' in " + antlib); continue; } String classname = def.getAttribute("classname"); // NOI18N if (classname == null) { // But this is a hard error. throw new IOException("No 'classname' attr on def of " + name + " in " + antlib); // NOI18N } // XXX would be good to handle at least onerror attr too (type ? newTypeDefs : newTaskDefs).setProperty(name, classname); } loadDefs(newTaskDefs, tasks, l); loadDefs(newTypeDefs, types, l); } return m; } private static void loadDefs(Properties p, Map defs, ClassLoader l) throws IOException { // Similar to IntrospectedInfo.load, after having parsed the properties. Iterator it = p.entrySet().iterator(); while (it.hasNext()) { Map.Entry entry = (Map.Entry)it.next(); String name = (String)entry.getKey(); String clazzname = (String)entry.getValue(); try { Class clazz = l.loadClass(clazzname); defs.put(name, clazz); } catch (ClassNotFoundException cnfe) { // This is not normal. If the class is mentioned, it should be there. IOException ioe = new IOException("Could not load class " + clazzname + ": " + cnfe); // NOI18N err.annotate(ioe, cnfe); throw ioe; } catch (NoClassDefFoundError ncdfe) { // Normal for e.g. tasks dumped there by disabled modules. // Cf. #36702 for possible better solution. err.log("AntBridge.loadDefs: skipping " + clazzname + ": " + ncdfe); } catch (LinkageError e) { // Not normal; if it is there it ought to be resolvable etc. IOException ioe = new IOException("Could not load class " + clazzname + ": " + e); // NOI18N err.annotate(ioe, e); throw ioe; } } } static class AllPermissionURLClassLoader extends URLClassLoader { private static PermissionCollection allPermission; private static synchronized PermissionCollection getAllPermissions() { if (allPermission == null) { allPermission = new Permissions(); allPermission.add(new AllPermission()); } return allPermission; } public AllPermissionURLClassLoader(URL[] urls, ClassLoader parent) { super(urls, parent); } protected final PermissionCollection getPermissions(CodeSource cs) { return getAllPermissions(); } public String toString() { return super.toString() + "[parent=" + getParent() + ",urls=" + Arrays.asList((Object[])getURLs()) + "]"; } public URL getResource(String name) { URL u = super.getResource(name); if (err.isLoggable(ErrorManager.INFORMATIONAL)) { err.log("APURLCL.gR: " + name + " -> " + u + " [" + this + "]"); } return u; } public Enumeration/**/ findResources(String name) throws IOException { try { Enumeration/**/ us = super.findResources(name); if (err.isLoggable(ErrorManager.INFORMATIONAL)) { // Make a copy so it can be logged: List/**/ resources = Collections.list(us); us = Collections.enumeration(resources); err.log("APURLCL.fRs: " + name + " -> " + resources + " [" + this + "]"); } return us; } catch (IOException e) { if (err.isLoggable(ErrorManager.INFORMATIONAL)) { err.notify(ErrorManager.INFORMATIONAL, e); } throw e; } } /* public Class loadClass(String name) throws ClassNotFoundException { try { Class c = super.loadClass(name); java.security.CodeSource s = c.getProtectionDomain().getCodeSource(); System.err.println("ACL.lC: " + name + " from " + (s != null ? s.getLocation() : null) + " [" + this + "]"); return c; } catch (ClassNotFoundException e) { System.err.println("ACL.lC: CNFE on " + name + " [" + this + "]"); throw e; } } */ } private static boolean masked(String clazz) { return clazz.startsWith("org.apache.tools.") || clazz.startsWith("org.netbeans."); // NOI18N } /** * Special class loader that refuses to load Ant or NetBeans classes from its parent. * Necessary in order to be able to load the intended Ant distro from a unit test. */ private static final class MaskedClassLoader extends AllPermissionURLClassLoader { public MaskedClassLoader(URL[] urls, ClassLoader parent) { super(urls, parent); } protected synchronized Class loadClass(String name, boolean resolve) throws ClassNotFoundException { if (masked(name)) { Class c = findLoadedClass(name); // Careful with that parent loader Eugene! if (c == null) { c = findClass(name); } if (resolve) { resolveClass(c); } return c; } else { return super.loadClass(name, resolve); } } } // I/O redirection impl. Keyed by thread group (each Ant process has its own TG). // Various Ant tasks (e.g. ) need the system // I/O streams to be redirected to the demux streams of the project so they can // be handled properly. Ideally nothing would try to read directly from stdin // or print directly to stdout/stderr but in fact some tasks do. // Could also pass a custom InputOutput to ExecutionEngine, perhaps, but this // seems a lot simpler and probably has the same effect. private static int delegating = 0; private static InputStream origIn; private static PrintStream origOut, origErr; private static Map/**/ delegateIns = new HashMap(); private static Map/**/ delegateOuts = new HashMap(); private static Map/**/ delegateErrs = new HashMap(); /** map, not set, so can be reentrant */ private static List/**/ suspendedDelegationTasks = new ArrayList(); /** * Handle I/O scoping for overlapping project runs. * You must call {@link #restoreSystemInOutErr} in a finally block. * @param in new temporary input stream for this thread group * @param out new temporary output stream for this thread group * @param err new temporary error stream for this thread group * @see "#36396" */ public static synchronized void pushSystemInOutErr(InputStream in, PrintStream out, PrintStream err) { if (delegating++ == 0) { origIn = System.in; origOut = System.out; origErr = System.err; System.setIn(new MultiplexInputStream()); System.setOut(new MultiplexPrintStream(false)); System.setErr(new MultiplexPrintStream(true)); } ThreadGroup tg = Thread.currentThread().getThreadGroup(); delegateIns.put(tg, in); delegateOuts.put(tg, out); delegateErrs.put(tg, err); } /** * Restore original I/O streams after a call to {@link #pushSystemInOutErr}. */ public static synchronized void restoreSystemInOutErr() { assert delegating > 0; if (--delegating == 0) { System.setIn(origIn); System.setOut(origOut); System.setErr(origErr); origIn = null; origOut = null; origErr = null; } ThreadGroup tg = Thread.currentThread().getThreadGroup(); delegateIns.remove(tg); delegateOuts.remove(tg); delegateErrs.remove(tg); } /** * Temporarily suspend delegation of system I/O streams for the current thread. * Useful when running callbacks to IDE code that might try to print to stderr etc. * Must be matched in a finally block by {@link #resumeDelegation}. * Safe to call when not actually delegating; in that case does nothing. * Safe to call in reentrant but not overlapping fashion. */ public static synchronized void suspendDelegation() { Thread t = Thread.currentThread(); //assert delegateOuts.containsKey(t.getThreadGroup()) : "Not currently delegating in " + t; assert !suspendedDelegationTasks.contains(t) : "Already suspended delegation in " + t; suspendedDelegationTasks.add(t); } /** * Resume delegation of system I/O streams for the current thread group * after a call to {@link #suspendDelegation}. */ public static synchronized void resumeDelegation() { Thread t = Thread.currentThread(); //assert delegateOuts.containsKey(t.getThreadGroup()) : "Not currently delegating in " + t; assert suspendedDelegationTasks.contains(t) : "Have not suspended delegation in " + t; suspendedDelegationTasks.remove(t); } private static final class MultiplexInputStream extends InputStream { public MultiplexInputStream() {} private InputStream delegate() { Thread t = Thread.currentThread(); ThreadGroup tg = t.getThreadGroup(); while (tg != null && !delegateIns.containsKey(tg)) { tg = tg.getParent(); } InputStream is = (InputStream)delegateIns.get(tg); if (is != null && !suspendedDelegationTasks.contains(t)) { return is; } else if (delegating > 0) { assert origIn != null; return origIn; } else { // Probably should not happen? But not sure. return System.in; } } public int read() throws IOException { return delegate().read(); } public int read(byte[] b) throws IOException { return delegate().read(b); } public int read(byte[] b, int off, int len) throws IOException { return delegate().read(b, off, len); } public int available() throws IOException { return delegate().available(); } public boolean markSupported() { return delegate().markSupported(); } public void mark(int readlimit) { delegate().mark(readlimit); } public void close() throws IOException { delegate().close(); } public long skip(long n) throws IOException { return delegate().skip(n); } public void reset() throws IOException { delegate().reset(); } } private static final class MultiplexPrintStream extends PrintStream { private final boolean err; public MultiplexPrintStream(boolean err) { this(new NullOutputStream(), err); } private MultiplexPrintStream(NullOutputStream nos, boolean err) { super(nos); nos.throwException = true; this.err = err; } private PrintStream delegate() { Thread t = Thread.currentThread(); ThreadGroup tg = t.getThreadGroup(); Map/**/ delegates = err ? delegateErrs : delegateOuts; while (tg != null && !delegates.containsKey(tg)) { tg = tg.getParent(); } PrintStream ps = (PrintStream)delegates.get(tg); if (ps != null && !suspendedDelegationTasks.contains(t)) { return ps; } else if (delegating > 0) { PrintStream orig = err ? origErr : origOut; assert orig != null; return orig; } else { // Probably should not happen? But not sure. return err ? System.err : System.out; } } public boolean checkError() { return delegate().checkError(); } public void close() { delegate().close(); } public void flush() { delegate().flush(); } public void print(long l) { delegate().print(l); } public void print(char[] s) { delegate().print(s); } public void print(int i) { delegate().print(i); } public void print(boolean b) { delegate().print(b); } public void print(char c) { delegate().print(c); } public void print(float f) { delegate().print(f); } public void print(double d) { delegate().print(d); } public void print(Object obj) { delegate().print(obj); } public void print(String s) { delegate().print(s); } public void println(double x) { delegate().println(x); } public void println(Object x) { delegate().println(x); } public void println(float x) { delegate().println(x); } public void println(int x) { delegate().println(x); } public void println(char x) { delegate().println(x); } public void println(boolean x) { delegate().println(x); } public void println(String x) { delegate().println(x); } public void println(char[] x) { delegate().println(x); } public void println() { delegate().println(); } public void println(long x) { delegate().println(x); } public void write(int b) { delegate().write(b); } public void write(byte[] b) throws IOException { delegate().write(b); } public void write(byte[] b, int off, int len) { delegate().write(b, off, len); } // XXX printf/format with varargs cannot be overridden here (JDK 1.5 specific) // nor can append(char,CharSequence) // probably does not matter however... } // Faking the system property java.class.path for the benefit of a few tasks // that expect it to be equal to the Ant class loader path. private static int fakingJavaClassPath = 0; /** * Fake the system property java.class.path temporarily. * Must be followed by {@link unfakeJavaClassPath} in a finally block. * Reentrant. */ public static synchronized void fakeJavaClassPath() { if (fakingJavaClassPath++ == 0) { String cp = getMainClassPath(); err.log("Faking java.class.path=" + cp); System.setProperty("java.class.path", cp); // NOI18N } } /** * Reverse the effect of {@link fakeJavaClassPath}. */ public static synchronized void unfakeJavaClassPath() { if (--fakingJavaClassPath == 0) { err.log("Restoring java.class.path=" + originalJavaClassPath); System.setProperty("java.class.path", originalJavaClassPath); // NOI18N } } }

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