jjg@441: /*
jjg@1753:  * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
jjg@441:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jjg@441:  *
jjg@441:  * This code is free software; you can redistribute it and/or modify it
jjg@441:  * under the terms of the GNU General Public License version 2 only, as
ohair@554:  * published by the Free Software Foundation.  Oracle designates this
jjg@441:  * particular file as subject to the "Classpath" exception as provided
ohair@554:  * by Oracle in the LICENSE file that accompanied this code.
jjg@441:  *
jjg@441:  * This code is distributed in the hope that it will be useful, but WITHOUT
jjg@441:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jjg@441:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jjg@441:  * version 2 for more details (a copy is included in the LICENSE file that
jjg@441:  * accompanied this code).
jjg@441:  *
jjg@441:  * You should have received a copy of the GNU General Public License version
jjg@441:  * 2 along with this work; if not, write to the Free Software Foundation,
jjg@441:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jjg@441:  *
ohair@554:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@554:  * or visit www.oracle.com if you need additional information or have any
ohair@554:  * questions.
jjg@441:  */
jjg@468: 
ohrstrom@1224: package genstubs;
ohrstrom@1224: 
jjg@441: import java.io.*;
jjg@441: import java.util.*;
jjg@441: import javax.tools.JavaFileObject;
jjg@441: import javax.tools.StandardJavaFileManager;
jjg@441: import javax.tools.StandardLocation;
jjg@441: 
jjg@441: import com.sun.source.tree.CompilationUnitTree;
jjg@441: import com.sun.source.util.JavacTask;
jjg@441: import com.sun.tools.javac.api.JavacTool;
jjg@441: import com.sun.tools.javac.code.Flags;
jjg@1379: import com.sun.tools.javac.code.TypeTag;
jjg@441: import com.sun.tools.javac.tree.JCTree;
jjg@1753: import com.sun.tools.javac.tree.JCTree.JCClassDecl;
jjg@441: import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;
jjg@468: import com.sun.tools.javac.tree.JCTree.JCFieldAccess;
jjg@468: import com.sun.tools.javac.tree.JCTree.JCIdent;
jjg@468: import com.sun.tools.javac.tree.JCTree.JCImport;
jjg@441: import com.sun.tools.javac.tree.JCTree.JCLiteral;
jjg@441: import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
jjg@441: import com.sun.tools.javac.tree.JCTree.JCModifiers;
jjg@441: import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
jjg@441: import com.sun.tools.javac.tree.Pretty;
jjg@468: import com.sun.tools.javac.tree.TreeMaker;
jjg@468: import com.sun.tools.javac.tree.TreeScanner;
jjg@441: import com.sun.tools.javac.tree.TreeTranslator;
jjg@468: import com.sun.tools.javac.util.Context;
jjg@468: import com.sun.tools.javac.util.ListBuffer;
jjg@468: import com.sun.tools.javac.util.Name;
jjg@468: import javax.tools.JavaFileManager;
jjg@441: 
jjg@441: /**
jjg@441:  * Generate stub source files by removing implementation details from input files.
jjg@441:  *
jjg@441:  * This is a special purpose stub generator, specific to the needs of generating
jjg@441:  * stub files for JDK 7 API that are needed to compile langtools files that depend
jjg@441:  * on that API. The stub generator works by removing as much of the API source code
jjg@441:  * as possible without affecting the public signature, in order to reduce the
jjg@441:  * transitive closure of the API being referenced. The resulting stubs can be
jjg@441:  * put on the langtools sourcepath with -implicit:none to compile the langtools
jjg@441:  * files that depend on the JDK 7 API.
jjg@441:  *
jjg@441:  * Usage:
jjg@441:  *  genstubs -s <outdir> -sourcepath <path> <classnames>
jjg@441:  *
jjg@441:  * The specified class names are looked up on the sourcepath, and corresponding
jjg@441:  * stubs are written to the source output directory.
jjg@441:  *
jjg@441:  * Classes are parsed into javac ASTs, then processed with a javac TreeTranslator
jjg@441:  * to remove implementation details, and written out in the source output directory.
jjg@441:  * Documentation comments and annotations are removed. Method bodies are removed
jjg@441:  * and methods are marked native. Private and package-private field definitions
jjg@441:  * have their initializers replace with 0, 0.0, false, null as appropriate.
jjg@441:  */
jjg@441: 
jjg@441: public class GenStubs {
jjg@441:     static class Fault extends Exception {
jjg@441:         private static final long serialVersionUID = 0;
jjg@441:         Fault(String message) {
jjg@441:             super(message);
jjg@441:         }
jjg@441:         Fault(String message, Throwable cause) {
jjg@441:             super(message);
jjg@441:             initCause(cause);
jjg@441:         }
jjg@441:     }
jjg@441: 
jjg@441:     public static void main(String[] args) {
jjg@441:         boolean ok = new GenStubs().run(args);
jjg@441:         if (!ok)
jjg@441:             System.exit(1);
jjg@441:     }
jjg@441: 
ohrstrom@1224:     public boolean run(String... args) {
jjg@441:         File outdir = null;
jjg@441:         String sourcepath = null;
jjg@441:         List<String> classes = new ArrayList<String>();
jjg@441:         for (ListIterator<String> iter = Arrays.asList(args).listIterator(); iter.hasNext(); ) {
jjg@441:             String arg = iter.next();
jjg@441:             if (arg.equals("-s") && iter.hasNext())
jjg@441:                 outdir = new File(iter.next());
jjg@441:             else if (arg.equals("-sourcepath") && iter.hasNext())
jjg@441:                 sourcepath = iter.next();
jjg@441:             else if (arg.startsWith("-"))
jjg@441:                 throw new IllegalArgumentException(arg);
jjg@441:             else {
jjg@441:                 classes.add(arg);
jjg@441:                 while (iter.hasNext())
jjg@441:                     classes.add(iter.next());
jjg@441:             }
jjg@441:         }
jjg@441: 
jjg@441:         return run(sourcepath, outdir, classes);
jjg@441:     }
jjg@441: 
ohrstrom@1224:     public boolean run(String sourcepath, File outdir, List<String> classes) {
jjg@441:         //System.err.println("run: sourcepath:" + sourcepath + " outdir:" + outdir + " classes:" + classes);
jjg@441:         if (sourcepath == null)
jjg@441:             throw new IllegalArgumentException("sourcepath not set");
jjg@441:         if (outdir == null)
jjg@441:             throw new IllegalArgumentException("source output dir not set");
jjg@441: 
jjg@441:         JavacTool tool = JavacTool.create();
jjg@441:         StandardJavaFileManager fm = tool.getStandardFileManager(null, null, null);
jjg@441: 
jjg@441:         try {
jjg@441:             fm.setLocation(StandardLocation.SOURCE_OUTPUT, Collections.singleton(outdir));
jjg@441:             fm.setLocation(StandardLocation.SOURCE_PATH, splitPath(sourcepath));
jjg@441:             List<JavaFileObject> files = new ArrayList<JavaFileObject>();
jjg@441:             for (String c: classes) {
jjg@441:                 JavaFileObject fo = fm.getJavaFileForInput(
jjg@441:                         StandardLocation.SOURCE_PATH, c, JavaFileObject.Kind.SOURCE);
jjg@441:                 if (fo == null)
jjg@441:                     error("class not found: " + c);
jjg@441:                 else
jjg@441:                     files.add(fo);
jjg@441:             }
jjg@441: 
jjg@441:             JavacTask t = tool.getTask(null, fm, null, null, null, files);
jjg@441:             Iterable<? extends CompilationUnitTree> trees = t.parse();
jjg@441:             for (CompilationUnitTree tree: trees) {
jjg@441:                 makeStub(fm, tree);
jjg@441:             }
jjg@441:         } catch (IOException e) {
jjg@441:             error("IO error " + e, e);
jjg@441:         }
jjg@441: 
jjg@441:         return (errors == 0);
jjg@441:     }
jjg@441: 
jjg@441:     void makeStub(StandardJavaFileManager fm, CompilationUnitTree tree) throws IOException {
jjg@441:         CompilationUnitTree tree2 = new StubMaker().translate(tree);
jjg@468:         CompilationUnitTree tree3 = new ImportCleaner(fm).removeRedundantImports(tree2);
jjg@441: 
jjg@441:         String className = fm.inferBinaryName(StandardLocation.SOURCE_PATH, tree.getSourceFile());
jjg@441:         JavaFileObject fo = fm.getJavaFileForOutput(StandardLocation.SOURCE_OUTPUT,
jjg@441:                 className, JavaFileObject.Kind.SOURCE, null);
jjg@441:         // System.err.println("Writing " + className + " to " + fo.getName());
jjg@441:         Writer out = fo.openWriter();
jjg@441:         try {
jjg@468:             new Pretty(out, true).printExpr((JCTree) tree3);
jjg@441:         } finally {
jjg@441:             out.close();
jjg@441:         }
jjg@441:     }
jjg@441: 
jjg@441:     List<File> splitPath(String path) {
jjg@441:         List<File> list = new ArrayList<File>();
jjg@441:         for (String p: path.split(File.pathSeparator)) {
jjg@441:             if (p.length() > 0)
jjg@441:                 list.add(new File(p));
jjg@441:         }
jjg@441:         return list;
jjg@441:     }
jjg@441: 
jjg@441:     void error(String message) {
jjg@441:         System.err.println(message);
jjg@441:         errors++;
jjg@441:     }
jjg@441: 
jjg@441:     void error(String message, Throwable cause) {
jjg@441:         error(message);
jjg@441:     }
jjg@441: 
jjg@441:     int errors;
jjg@441: 
jjg@441:     class StubMaker extends TreeTranslator {
jjg@441:         CompilationUnitTree translate(CompilationUnitTree tree) {
jjg@441:             return super.translate((JCCompilationUnit) tree);
jjg@441:         }
jjg@441: 
jjg@441:         /**
jjg@441:          * compilation units: remove javadoc comments
jjg@441:          * -- required, in order to remove @deprecated tags, since we
jjg@441:          * (separately) remove all annotations, including @Deprecated
jjg@441:          */
jjg@441:         public void visitTopLevel(JCCompilationUnit tree) {
jjg@441:             super.visitTopLevel(tree);
erikj@1286:             tree.docComments = null;
jjg@441:         }
jjg@441: 
jjg@441:         /**
jjg@441:          * methods: remove method bodies, make methods native
jjg@441:          */
jjg@441:         @Override
jjg@1753:         public void visitClassDef(JCClassDecl tree) {
jjg@1753:             long prevClassMods = currClassMods;
jjg@1753:             currClassMods = tree.mods.flags;
jjg@1753:             try {
jjg@1753:                 super.visitClassDef(tree);;
jjg@1753:             } finally {
jjg@1753:                 currClassMods = prevClassMods;
jjg@1753:             }
jjg@1753:         }
jjg@1753:         private long currClassMods = 0;
jjg@1753: 
jjg@1753:         /**
jjg@1753:          * methods: remove method bodies, make methods native
jjg@1753:          */
jjg@1753:         @Override
jjg@441:         public void visitMethodDef(JCMethodDecl tree) {
jjg@441:             tree.mods = translate(tree.mods);
jjg@441:             tree.restype = translate(tree.restype);
jjg@441:             tree.typarams = translateTypeParams(tree.typarams);
jjg@441:             tree.params = translateVarDefs(tree.params);
jjg@441:             tree.thrown = translate(tree.thrown);
jjg@1786:             if (tree.body != null) {
jjg@1753:                 if ((currClassMods & Flags.INTERFACE) != 0) {
jjg@1786:                     tree.mods.flags &= ~(Flags.DEFAULT | Flags.STATIC);
jjg@1753:                 } else {
jjg@1753:                     tree.mods.flags |= Flags.NATIVE;
jjg@1753:                 }
jjg@441:                 tree.body = null;
jjg@441:             }
jjg@441:             result = tree;
jjg@441:         }
jjg@441: 
jjg@441:         /**
jjg@441:          * modifiers: remove annotations
jjg@441:          */
jjg@441:         @Override
jjg@441:         public void visitModifiers(JCModifiers tree) {
jjg@441:             tree.annotations = com.sun.tools.javac.util.List.nil();
jjg@441:             result = tree;
jjg@441:         }
jjg@441: 
jjg@441:         /**
jjg@441:          * field definitions: replace initializers with 0, 0.0, false etc
jjg@441:          * when possible -- i.e. leave public, protected initializers alone
jjg@441:          */
jjg@441:         @Override
jjg@441:         public void visitVarDef(JCVariableDecl tree) {
jjg@441:             tree.mods = translate(tree.mods);
jjg@441:             tree.vartype = translate(tree.vartype);
jjg@441:             if (tree.init != null) {
jjg@441:                 if ((tree.mods.flags & (Flags.PUBLIC | Flags.PROTECTED)) != 0)
jjg@441:                     tree.init = translate(tree.init);
jjg@441:                 else {
jjg@441:                     String t = tree.vartype.toString();
jjg@441:                     if (t.equals("boolean"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.BOOLEAN, 0) { };
jjg@441:                     else if (t.equals("byte"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.BYTE, 0) { };
jjg@441:                     else if (t.equals("char"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.CHAR, 0) { };
jjg@441:                     else if (t.equals("double"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.DOUBLE, 0.d) { };
jjg@441:                     else if (t.equals("float"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.FLOAT, 0.f) { };
jjg@441:                     else if (t.equals("int"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.INT, 0) { };
jjg@441:                     else if (t.equals("long"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.LONG, 0) { };
jjg@441:                     else if (t.equals("short"))
jjg@1379:                         tree.init = new JCLiteral(TypeTag.SHORT, 0) { };
jjg@441:                     else
jjg@1379:                         tree.init = new JCLiteral(TypeTag.BOT, null) { };
jjg@441:                 }
jjg@441:             }
jjg@441:             result = tree;
jjg@441:         }
jjg@441:     }
jjg@441: 
jjg@468:     class ImportCleaner extends TreeScanner {
jjg@468:         private Set<Name> names = new HashSet<Name>();
jjg@468:         private TreeMaker m;
jjg@468: 
jjg@468:         ImportCleaner(JavaFileManager fm) {
jjg@468:             // ImportCleaner itself doesn't require a filemanager, but instantiating
jjg@468:             // a TreeMaker does, indirectly (via ClassReader, sigh)
jjg@468:             Context c = new Context();
jjg@468:             c.put(JavaFileManager.class, fm);
jjg@468:             m = TreeMaker.instance(c);
jjg@468:         }
jjg@468: 
jjg@468:         CompilationUnitTree removeRedundantImports(CompilationUnitTree t) {
jjg@468:             JCCompilationUnit tree = (JCCompilationUnit) t;
jjg@468:             tree.accept(this);
jjg@468:             ListBuffer<JCTree> defs = new ListBuffer<JCTree>();
jjg@468:             for (JCTree def: tree.defs) {
ohrstrom@1224:                 if (def.getTag() == JCTree.Tag.IMPORT) {
jjg@468:                     JCImport imp = (JCImport) def;
ohrstrom@1224:                     if (imp.qualid.getTag() == JCTree.Tag.SELECT) {
jjg@468:                         JCFieldAccess qualid = (JCFieldAccess) imp.qualid;
jjg@468:                         if (!qualid.name.toString().equals("*")
jjg@468:                                 && !names.contains(qualid.name)) {
jjg@468:                             continue;
jjg@468:                         }
jjg@468:                     }
jjg@468:                 }
jjg@468:                 defs.add(def);
jjg@468:             }
jjg@468:             return m.TopLevel(tree.packageAnnotations, tree.pid, defs.toList());
jjg@468:         }
jjg@468: 
jjg@468:         @Override
jjg@468:         public void visitImport(JCImport tree) { } // ignore names found in imports
jjg@468: 
jjg@468:         @Override
jjg@468:         public void visitIdent(JCIdent tree) {
jjg@468:             names.add(tree.name);
jjg@468:         }
jjg@468: 
jjg@468:         @Override
jjg@468:         public void visitSelect(JCFieldAccess tree) {
jjg@468:             super.visitSelect(tree);
jjg@468:             names.add(tree.name);
jjg@468:         }
jjg@468:     }
jjg@441: }