Fix javac --incremental by using jmake for dependency analysis

third_party/jmake/src/org/pantsbuild/jmake/ClassPath.java

Index: third_party/jmake/src/org/pantsbuild/jmake/ClassPath.java
diff --git a/third_party/jmake/src/org/pantsbuild/jmake/ClassPath.java b/third_party/jmake/src/org/pantsbuild/jmake/ClassPath.java
new file mode 100644
index 0000000000000000000000000000000000000000..e6e1aebd86a31054fc802960991986414288ef01
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+++ b/third_party/jmake/src/org/pantsbuild/jmake/ClassPath.java
@@ -0,0 +1,448 @@
+/* Copyright (c) 2002-2008 Sun Microsystems, Inc. All rights reserved
+ *
+ * This program is distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+package org.pantsbuild.jmake;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Set;
+import java.util.StringTokenizer;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
+
+/**
+ * An instance of this class represents a class path, on which binary classes can be looked up.
+ * It also provides several static methods to create and utilize several specific class paths used
+ * throughout jmake.
+ *
+ * @author Misha Dmitriev
+ *  12 October 2004
+ */
+public class ClassPath {
+
+    private PathEntry[] paths;
+    private static ClassPath projectClassPath;   // Class path (currently it can contain only JARs) containing sourceless project classes.
+    // See also the comment to standardClassPath.
+    private static ClassPath standardClassPath;  // Class path that the user specifies via the -classpath option. A sum of the
+    // standardClassPath, the projectClassPath, and the virtualPath is passed to the compiler. Each of these
+    // class paths are also used to look up non-project superclasses/superinterfaces of
+    // project classes.
+    private static ClassPath bootClassPath,  extClassPath; // Class paths that by default are sun.boot.class.path and all JARs on
+    // java.ext.class.path, respectively. They are used to look up non-project
+    // superclasses/superinterfaces of project classes. Their values can be changed using
+    // setBootClassPath() and setExtDirs().
+    private static ClassPath virtualPath; // Class path that the user specifies via the -vpath option.
+    private static String compilerUserClassPath; // Class path to be passed to the compiler; equals to the sum of values of parameters of
+    // setClassPath() and setProjectClassPath() methods.
+    private static String standardClassPathStr,  projectClassPathStr,  bootClassPathStr,  extDirsStr,
+            virtualPathStr;
+    private static Map<String,ClassInfo> classCache;
+
+
+    static {
+        resetOnFinish();
+    }
+
+    /**
+     * Needed since some environments, e.g. NetBeans, can keep jmake classes in memory
+     * permanently. Thus unchanged class paths from previous, possibly unrelated invocations
+     * of jmake, may interfere with the current settings.
+     */
+    public static void resetOnFinish() {
+        projectClassPath = standardClassPath = bootClassPath = extClassPath = virtualPath =
+                null;
+        compilerUserClassPath = null;
+        standardClassPathStr = projectClassPathStr = bootClassPathStr =
+                extDirsStr = virtualPathStr = null;
+        classCache = new LinkedHashMap<String,ClassInfo>();
+    }
+
+    public static void setClassPath(String value) throws PublicExceptions.InvalidCmdOptionException {
+        standardClassPathStr = value;
+        standardClassPath = new ClassPath(value, false);
+    }
+
+    public static void setProjectClassPath(String value) throws PublicExceptions.InvalidCmdOptionException {
+        projectClassPathStr = value;
+        projectClassPath = new ClassPath(value, true);
+    }
+
+    public static void setBootClassPath(String value) throws PublicExceptions.InvalidCmdOptionException {
+        bootClassPathStr = value;
+        bootClassPath = new ClassPath(value, false);
+    }
+
+    public static void setExtDirs(String value) throws PublicExceptions.InvalidCmdOptionException {
+        extDirsStr = value;
+        // Extension class path needs special handling, since it consists of directories, which contain .jars
+        // So we need to find all these .jars in all these dirs and add them to extClassPathElementList
+        List<String> extClassPathElements = new ArrayList<String>();
+        for (StringTokenizer tok =
+                new StringTokenizer(value, File.pathSeparator); tok.hasMoreTokens();) {
+            File extDir = new File(tok.nextToken());
+            String[] extJars = extDir.list(new FilenameFilter() {
+
+                public boolean accept(File dir, String name) {
+                    name = name.toLowerCase(Locale.ENGLISH);
+                    return name.endsWith(".zip") || name.endsWith(".jar");
+                }
+            });
+            if (extJars == null) {
+                continue;
+            }
+            for (int i = 0; i < extJars.length; i++) {
+                extClassPathElements.add(extDir + File.separator + extJars[i]);
+            }
+        }
+        extClassPath = new ClassPath(extClassPathElements, false);
+    }
+
+    public static void setVirtualPath(String value) throws PublicExceptions.InvalidCmdOptionException {
+        if (value == null) {
+            throw new PublicExceptions.InvalidCmdOptionException("null argument");
+        }
+        StringTokenizer st = new StringTokenizer(value, File.pathSeparator);
+        while (st.hasMoreElements()) {
+            String dir = st.nextToken();
+            if ( ! (new File(dir)).isDirectory()) {
+                throw new PublicExceptions.InvalidCmdOptionException("Virtual path must contain only directories." +
+                        " Entry " + dir + " is not a directory.");
+            }
+        }
+        virtualPathStr = value;
+        virtualPath = new ClassPath(value, false);
+    }
+
+    public static void initializeAllClassPaths() {
+        // First set the compiler class path value
+        if (standardClassPathStr == null && projectClassPathStr == null) {
+            compilerUserClassPath = ".";
+        } else if (standardClassPathStr == null) {
+            compilerUserClassPath = projectClassPathStr;
+        } else if (projectClassPathStr == null) {
+            compilerUserClassPath = standardClassPathStr;
+        } else {
+            compilerUserClassPath =
+                    standardClassPathStr + File.pathSeparator + projectClassPathStr;
+        }
+
+        if (virtualPathStr != null) {
+            compilerUserClassPath += File.pathSeparator + virtualPathStr;
+        }
+
+        if (standardClassPathStr == null) {
+            try {
+                String tmp = ".";
+                if (virtualPathStr != null) {
+                    tmp += File.pathSeparator + virtualPathStr;
+                }
+                standardClassPath = new ClassPath(tmp, false);
+            } catch (PublicExceptions.InvalidCmdOptionException ex) { /* Should not happen */ }
+        }
+        if (projectClassPathStr == null) {
+            projectClassPath = new ClassPath();
+        }
+
+        // Create the core class path as a combination of sun.boot.class.path and java.ext.dirs contents
+        if (bootClassPathStr == null) {
+            try {
+                bootClassPath =
+                        new ClassPath(System.getProperty("sun.boot.class.path"), false);
+            } catch (PublicExceptions.InvalidCmdOptionException ex) { /* Shouldn't happen */ }
+        // bootClassPathStr should remain null, so that nothing that the user didn't specify is passed to the compiler
+        }
+
+        if (extDirsStr == null) {
+            try {
+                setExtDirs(System.getProperty("java.ext.dirs"));
+            } catch (PublicExceptions.InvalidCmdOptionException ex) { /* Shouldn't happen */ }
+            // extDirsStr should remain null, so that nothing that the user didn't specify is passed to the compiler
+            extDirsStr = null;
+        }
+    }
+
+    /** Never returns null - if classpath wasn't set explicitly, returns "." */
+    public static String getCompilerUserClassPath() {
+        return compilerUserClassPath;
+    }
+
+    /** Will return null if boot class path wasn't explicitly specified */
+    public static String getCompilerBootClassPath() {
+        return bootClassPathStr;
+    }
+
+    /** Will return null if extdirs weren't explicitly specified */
+    public static String getCompilerExtDirs() {
+        return extDirsStr;
+    }
+
+    /** Will return null if virtualPath wasn't explicitly specified */
+    public static String getVirtualPath() {
+        return virtualPathStr;
+    }
+
+    /**
+     * For the given class return the list of all of its superclasses (excluding Object), that can be loaded from
+     * projectClassPath or standardClassPath, plus the first superclass that can be loaded from coreClassPath.
+     * The latter is an optimization based on the assumption that core classes never change, or rather the programmer
+     * will recompile everything when they switch to a new JDK version. The optimization prevents us from wasting time
+     * repeatedly loading the same sets of core classes.
+     */
+    public static void getSuperclasses(String className,
+            Collection<String> res, PCDManager pcdm) {
+        int iterNo = 0;
+        while (!"java/lang/Object".equals(className)) {
+            ClassInfo ci = getClassInfoForName(className, pcdm);
+            if (ci == null) {
+                return;
+            }
+            if (iterNo++ > 0) {
+                res.add(ci.name);
+            }
+            className = ci.superName;
+        }
+    }
+
+    /**
+     * Add to the given set the names of all interfaces implemented by the given class, that can be loaded from
+     * projectClassPath or standardClassPath, plus the first interface on each branch that can be loaded from
+     * coreClassPath. It's the same optimization as in getSuperclasses().
+     */
+    public static void addAllImplementedInterfaceNames(String className,
+            Set<String> intfSet, PCDManager pcdm) {
+        if ("java/lang/Object".equals(className)) {
+            return;
+        }
+        ClassInfo ci = getClassInfoForName(className, pcdm);
+        if (ci == null) {
+            return;
+        }
+        String[] interfaces = ci.interfaces;
+        if (interfaces != null) {
+            for (int i = 0; i < interfaces.length; i++) {
+                intfSet.add(interfaces[i]);
+                addAllImplementedInterfaceNames(interfaces[i], intfSet, pcdm);
+            }
+        }
+
+        String superName = ci.superName;
+        if (superName != null) {
+            addAllImplementedInterfaceNames(superName, intfSet, pcdm);
+        }
+    }
+
+    public static String[] getProjectJars() {
+        if (projectClassPath == null || projectClassPath.isEmpty()) {
+            return null;
+        }
+        PathEntry paths[] = projectClassPath.paths;
+        String[] ret = new String[paths.length];
+        for (int i = 0; i < paths.length; i++) {
+            ret[i] = paths[i].toString();
+        }
+        return ret;
+    }
+
+    public static ClassInfo getClassInfoForName(String className, PCDManager pcdm) {
+        ClassInfo info = classCache.get(className);
+        if (info != null) {
+            return info;
+        }
+
+        byte buf[] = bootClassPath.getBytesForClass(className);
+        if (buf == null) {
+            buf = extClassPath.getBytesForClass(className);
+        }
+        if (buf == null) {
+            buf = standardClassPath.getBytesForClass(className);
+        }
+        if (buf == null) {
+            buf = projectClassPath.getBytesForClass(className);
+        }
+        if (buf == null) {
+            return null;
+        }
+
+        info = new ClassInfo(buf, pcdm, className);
+        classCache.put(className, info);
+        return info;
+    }
+
+    /** Returns the class loader that would load classes from the given class path. */
+    public static ClassLoader getClassLoaderForPath(String classPath) throws Exception {
+        boolean isWindows = System.getProperty("os.name").startsWith("Win");
+        ClassPath cp = new ClassPath(classPath, false);
+        PathEntry[] paths = cp.paths;
+        URL[] urls = new URL[paths.length];
+        for (int i = 0; i < paths.length; i++) {
+            String dirOrJar = paths[i].toString();
+            if (!(dirOrJar.startsWith("file://") || dirOrJar.startsWith("http://"))) {
+                // On Windows, if I have path specified as "file://c:\...", (i.e. with the drive name) URLClassLoader works
+                // unbelievably slow. However, if an additional slash is added, like : "file:///c:\...", the speed becomes
+                // normal. To me it looks like a bug, but, anyway, I am taking measure here.
+                if (isWindows && dirOrJar.charAt(1) == ':') {
+                    dirOrJar = "/" + dirOrJar;
+                }
+                dirOrJar = new File(dirOrJar).toURI().toString();
+            }
+            if (!(dirOrJar.endsWith(".jar") || dirOrJar.endsWith(".zip") || dirOrJar.endsWith(File.separator))) {
+                dirOrJar += File.separator; // So that URLClassLoader correctly handles it as a directory
+            }
+            urls[i] = new URL(dirOrJar);
+        }
+
+        return new URLClassLoader(urls);
+    //} catch (java.net.MalformedURLException e) {
+
+    //}
+    }
+
+
+    // ------------------------------------ Private implementation --------------------------------------------
+    private ClassPath() {
+        paths = new PathEntry[0];
+    }
+
+    private ClassPath(String classPath, boolean isJarOnly) throws PublicExceptions.InvalidCmdOptionException {
+        if (classPath == null) {
+            throw new PublicExceptions.InvalidCmdOptionException("null argument");
+        }
+        List<String> vec = new ArrayList<String>();
+
+        for (StringTokenizer tok =
+                new StringTokenizer(classPath, File.pathSeparator); tok.hasMoreTokens();) {
+            String path = tok.nextToken();
+            vec.add(path);
+        }
+        init(vec, isJarOnly);
+    }
+
+    private ClassPath(List<String> pathEntries, boolean isJarOnly) throws PublicExceptions.InvalidCmdOptionException {
+        init(pathEntries, isJarOnly);
+    }
+
+    private void init(List<String> pathEntries, boolean isJarOnly) throws PublicExceptions.InvalidCmdOptionException {
+        if (pathEntries == null) {
+            throw new PublicExceptions.InvalidCmdOptionException("null argument");
+        }
+        List<PathEntry> vec = new ArrayList<PathEntry>(pathEntries.size());
+        for (int i = 0; i < pathEntries.size(); i++) {
+            String path = pathEntries.get(i);
+            if (!path.equals("")) {
+                File file = new File(path);
+                try {
+                    if (file.exists() && file.canRead()) {
+                        if (file.isDirectory()) {
+                            if (isJarOnly) {
+                                throw new PublicExceptions.InvalidCmdOptionException("directories are not allowed on this class path: " + path);
+                            }
+                            vec.add(new Dir(file));
+                        } else {
+                            vec.add(new Zip(new ZipFile(file)));
+                        }
+                    } else if (isJarOnly) {
+                        throw new IOException("file does not exist");
+                    }
+                } catch (IOException e) {
+                    if (isJarOnly) {
+                        throw new PublicExceptions.InvalidCmdOptionException("error initializing class path component " + path + ": " + e.getMessage());
+                    }
+                }
+            }
+        }
+
+        paths = new PathEntry[vec.size()];
+        vec.toArray(paths);
+    }
+
+    private boolean isEmpty() {
+        return paths.length == 0;
+    }
+
+    private byte[] getBytesForClass(String className) {
+        String fileName = className + ".class";
+        for (int i = 0; i < paths.length; i++) {
+            byte buf[] = paths[i].getBytesForClassFile(fileName);
+            if (buf != null) {
+                return buf;
+            }
+        }
+        return null;
+    }
+
+    public String toString() {
+        if (paths == null) {
+            return "NULL";
+        }
+        StringBuilder res = new StringBuilder();
+        for (int i = 0; i < paths.length; i++) {
+            res.append(paths[i].toString());
+        }
+        return res.toString();
+    }
+
+
+    // ------------------------------------ Private helper classes --------------------------------------------
+    private static abstract class PathEntry {
+
+        abstract byte[] getBytesForClassFile(String fileName);
+
+        public abstract String toString();
+    }
+
+    private static class Dir extends PathEntry {
+
+        private String dir;
+
+        Dir(File f) throws IOException {
+            dir = f.getCanonicalPath();
+        }
+
+        byte[] getBytesForClassFile(String fileName) {
+            File file = new File(dir + File.separatorChar + fileName);
+            if (file.exists()) {
+                return Utils.readFileIntoBuffer(file);
+            } else {
+                return null;
+            }
+        }
+
+        public String toString() {
+            return dir;
+        }
+    }
+
+    private static class Zip extends PathEntry {
+
+        private ZipFile zip;
+
+        Zip(ZipFile z) {
+            zip = z;
+        }
+
+        byte[] getBytesForClassFile(String fileName) {
+            ZipEntry entry = zip.getEntry(fileName);
+            if (entry != null) {
+                return Utils.readZipEntryIntoBuffer(zip, entry);
+            } else {
+                return null;
+            }
+        }
+
+        public String toString() {
+            return zip.getName();
+        }
+    }
+}