jaroslav@106: /**
jaroslav@106:  * Back 2 Browser Bytecode Translator
jaroslav@106:  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
jaroslav@106:  *
jaroslav@106:  * This program is free software: you can redistribute it and/or modify
jaroslav@106:  * it under the terms of the GNU General Public License as published by
jaroslav@106:  * the Free Software Foundation, version 2 of the License.
jaroslav@106:  *
jaroslav@106:  * This program is distributed in the hope that it will be useful,
jaroslav@106:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
jaroslav@106:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
jaroslav@106:  * GNU General Public License for more details.
jaroslav@106:  *
jaroslav@106:  * You should have received a copy of the GNU General Public License
jaroslav@106:  * along with this program. Look for COPYING file in the top folder.
jaroslav@106:  * If not, see http://opensource.org/licenses/GPL-2.0.
jaroslav@106:  */
jaroslav@29: package org.apidesign.vm4brwsr;
jaroslav@29: 
jaroslav@29: import java.io.BufferedWriter;
jaroslav@29: import java.io.FileWriter;
jaroslav@29: import java.io.IOException;
jaroslav@29: import java.io.InputStream;
jaroslav@29: import java.io.Writer;
jaroslav@93: import java.net.URL;
jaroslav@29: import java.util.Arrays;
jaroslav@97: import java.util.Collections;
jaroslav@93: import java.util.Enumeration;
jaroslav@97: import java.util.HashMap;
jaroslav@97: import java.util.Iterator;
jaroslav@29: import java.util.LinkedList;
jaroslav@29: import java.util.List;
jaroslav@97: import java.util.Map;
jaroslav@29: 
jaroslav@29: /** Generator of JavaScript from bytecode of classes on classpath of the VM.
jaroslav@29:  *
jaroslav@29:  * @author Jaroslav Tulach <jtulach@netbeans.org>
jaroslav@29:  */
jaroslav@29: final class GenJS {
jaroslav@29:     private GenJS() {}
jaroslav@29:     
jaroslav@29:     public static void main(String... args) throws IOException {
jaroslav@29:         if (args.length < 2) {
jaroslav@29:             System.err.println("Usage: java -cp ... -jar ... <file_to_generate_js_code_to> java/lang/Class org/your/App ...");
jaroslav@29:             return;
jaroslav@29:         }
jaroslav@29:         
jaroslav@29:         Writer w = new BufferedWriter(new FileWriter(args[0]));
jaroslav@29:         List<String> classes = Arrays.asList(args).subList(1, args.length);
jaroslav@29:         compile(w, classes);
jaroslav@29:         w.close();
jaroslav@29:     }
jaroslav@29:     
jaroslav@29:     static void compile(Appendable out, String... names) throws IOException {
jaroslav@29:         compile(out, Arrays.asList(names));
jaroslav@29:     }
jaroslav@29:     static void compile(Appendable out, List<String> names) throws IOException {
jaroslav@97:         for (String baseClass : names) {
jaroslav@97:             Map<String,String> processed = new HashMap<String, String>();
jaroslav@97:             LinkedList<String> toProcess = new LinkedList<String>();
jaroslav@97:             toProcess.add(baseClass);
jaroslav@97:             for (;;) {
jaroslav@97:                 String name = null;
jaroslav@97:                 Iterator<String> it = toProcess.iterator();
jaroslav@97:                 while (it.hasNext() && name == null) {
jaroslav@97:                     String n = it.next();
jaroslav@97:                     if (processed.get(n) != null) {
jaroslav@97:                         continue;
jaroslav@97:                     }
jaroslav@97:                     name = n;
jaroslav@97:                 }
jaroslav@97:                 if (name == null) {
jaroslav@97:                     break;
jaroslav@97:                 }
jaroslav@97:                 if (name.startsWith("java/")
jaroslav@97:                     && !name.equals("java/lang/Object")
jaroslav@97:                     && !name.equals("java/lang/Class")
jaroslav@104:                     && !name.equals("java/lang/Math")
jaroslav@97:                     && !name.equals("java/lang/Number")
jaroslav@97:                     && !name.equals("java/lang/Integer")
jaroslav@104:                     && !name.equals("java/lang/Float")
jaroslav@104:                     && !name.equals("java/lang/Double")
jaroslav@97:                     && !name.equals("java/lang/Throwable")
jaroslav@97:                     && !name.equals("java/lang/Exception")
jaroslav@97:                     && !name.equals("java/lang/RuntimeException")
jaroslav@97:                     && !name.equals("java/lang/UnsupportedOperationException")
jaroslav@97:                     && !name.equals("java/lang/String")
jaroslav@97:                     && !name.equals("java/lang/String$CaseInsensitiveComparator")
jaroslav@97:                     && !name.equals("java/lang/StringBuilder")
jaroslav@97:                     && !name.equals("java/lang/AbstractStringBuilder")
jaroslav@97:                 ) {
jaroslav@97:                     processed.put(name, "");
jaroslav@97:                     continue;
jaroslav@97:                 }            
jaroslav@97:                 InputStream is = loadClass(name);
jaroslav@97:                 if (is == null) {
jaroslav@97:                     throw new IOException("Can't find class " + name); 
jaroslav@97:                 }
jaroslav@97:                 LinkedList<String> scripts = new LinkedList<String>();
jaroslav@97:                 try {
jaroslav@97:                     String initCode = ByteCodeToJavaScript.compile(is, out, toProcess, scripts);
jaroslav@97:                     processed.put(name, initCode == null ? "" : initCode);
jaroslav@97:                 } catch (RuntimeException ex) {
jaroslav@97:                     if (out instanceof CharSequence) {
jaroslav@97:                         CharSequence seq = (CharSequence)out;
jaroslav@97:                         int lastBlock = seq.length();
jaroslav@97:                         while (lastBlock-- >= 0) {
jaroslav@97:                             if (seq.charAt(lastBlock) == '{') {
jaroslav@97:                                 break;
jaroslav@97:                             }
jaroslav@29:                         }
jaroslav@97:                         throw new IOException("Error while compiling " + name + "\n" 
jaroslav@97:                             + seq.subSequence(lastBlock + 1, seq.length()), ex
jaroslav@97:                         );
jaroslav@97:                     } else {
jaroslav@97:                         throw new IOException("Error while compiling " + name + "\n" 
jaroslav@97:                             + out, ex
jaroslav@97:                         );
jaroslav@29:                     }
jaroslav@97:                 }
jaroslav@97:                 for (String resource : scripts) {
jaroslav@97:                     InputStream emul = GenJS.class.getResourceAsStream(resource);
jaroslav@97:                     if (emul == null) {
jaroslav@97:                         throw new IOException("Can't find " + resource);
jaroslav@97:                     }
jaroslav@97:                     readResource(emul, out);
jaroslav@29:                 }
jaroslav@29:             }
jaroslav@97:             
jaroslav@97:             Collections.reverse(toProcess);
jaroslav@97: 
jaroslav@97:             for (String clazz : toProcess) {
jaroslav@97:                 String initCode = processed.remove(clazz);
jaroslav@97:                 if (initCode != null) {
jaroslav@97:                     out.append(initCode).append("\n");
jaroslav@91:                 }
jaroslav@91:             }
jaroslav@29:         }
jaroslav@29:     }
jaroslav@90:     private static void readResource(InputStream emul, Appendable out) throws IOException {
jaroslav@90:         try {
jaroslav@90:             int state = 0;
jaroslav@90:             for (;;) {
jaroslav@90:                 int ch = emul.read();
jaroslav@90:                 if (ch == -1) {
jaroslav@90:                     break;
jaroslav@90:                 }
jaroslav@90:                 if (ch < 0 || ch > 255) {
jaroslav@90:                     throw new IOException("Invalid char in emulation " + ch);
jaroslav@90:                 }
jaroslav@90:                 switch (state) {
jaroslav@90:                     case 0: 
jaroslav@90:                         if (ch == '/') {
jaroslav@90:                             state = 1;
jaroslav@90:                         } else {
jaroslav@90:                             out.append((char)ch);
jaroslav@90:                         }
jaroslav@90:                         break;
jaroslav@90:                     case 1:
jaroslav@90:                         if (ch == '*') {
jaroslav@90:                             state = 2;
jaroslav@90:                         } else {
jaroslav@90:                             out.append('/').append((char)ch);
jaroslav@90:                             state = 0;
jaroslav@90:                         }
jaroslav@90:                         break;
jaroslav@90:                     case 2:
jaroslav@90:                         if (ch == '*') {
jaroslav@90:                             state = 3;
jaroslav@90:                         }
jaroslav@90:                         break;
jaroslav@90:                     case 3:
jaroslav@90:                         if (ch == '/') {
jaroslav@90:                             state = 0;
jaroslav@90:                         } else {
jaroslav@90:                             state = 2;
jaroslav@90:                         }
jaroslav@90:                         break;
jaroslav@90:                 }
jaroslav@90:             }
jaroslav@90:         } finally {
jaroslav@90:             emul.close();
jaroslav@90:         }
jaroslav@90:     }
jaroslav@93: 
jaroslav@93:     private static InputStream loadClass(String name) throws IOException {
jaroslav@93:         Enumeration<URL> en = ClassLoader.getSystemClassLoader().getResources(name + ".class");
jaroslav@93:         URL u = null;
jaroslav@93:         while (en.hasMoreElements()) {
jaroslav@93:             u = en.nextElement();
jaroslav@93:         }
jaroslav@93:         if (u == null) {
jaroslav@93:             throw new IOException("Can't find " + name);
jaroslav@93:         }
jaroslav@93:         return u.openStream();
jaroslav@93:     }
jaroslav@29:     
jaroslav@29: }