2 * Back 2 Browser Bytecode Translator
3 * Copyright (C) 2012-2015 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, version 2 of the License.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. Look for COPYING file in the top folder.
16 * If not, see http://opensource.org/licenses/GPL-2.0.
18 package org.apidesign.vm4brwsr;
20 import java.io.IOException;
21 import java.io.InputStream;
22 import org.apidesign.bck2brwsr.core.JavaScriptBody;
23 import org.apidesign.vm4brwsr.Bck2Brwsr.Flow;
24 import org.apidesign.vm4brwsr.ByteCodeParser.ClassData;
25 import org.apidesign.vm4brwsr.ByteCodeParser.FieldData;
26 import org.apidesign.vm4brwsr.ByteCodeParser.MethodData;
28 /** Generator of JavaScript from bytecode of classes on classpath of the VM.
30 * @author Jaroslav Tulach <jtulach@netbeans.org>
32 abstract class VM extends ByteCodeToJavaScript {
33 protected final ClassDataCache classDataCache;
35 private final Bck2Brwsr.Resources resources;
36 private final ExportedSymbols exportedSymbols;
37 private final StringBuilder invokerMethods;
38 private final StringArray asBinary;
39 private final Flow.Analyzer flow;
43 Appendable out, Bck2Brwsr.Resources resources,
44 StringArray explicitlyExported, StringArray asBinary, Flow.Analyzer flow
47 this.resources = resources;
48 this.classDataCache = new ClassDataCache(resources);
49 this.exportedSymbols = new ExportedSymbols(resources, explicitlyExported);
50 this.invokerMethods = new StringBuilder();
51 this.asBinary = asBinary;
56 // uses VMLazy to load dynamic classes
57 boolean assertsOn = false;
58 assert assertsOn = true;
66 boolean debug(String msg) throws IOException {
70 static void compile(Appendable out,
72 ) throws IOException {
73 String[] both = config.classes().toArray();
75 final StringArray fixedNames = new StringArray();
76 fixedNames.add(Object.class.getName().replace('.', '/'));
77 fixedNames.add(Class.class.getName().replace('.', '/'));
78 fixedNames.add(ArithmeticException.class.getName().replace('.', '/'));
81 if (config.isExtension()) {
82 fixedNames.add(VM.class.getName().replace('.', '/'));
83 vm = new Extension(out,
84 config.getResources(), both, config.exported(),
85 config.allResources(), config.classpath(),
89 if (config.includeVM()) {
90 fixedNames.add(VM.class.getName().replace('.', '/'));
92 vm = new Standalone(out,
93 config.getResources(), config.exported(),
94 config.allResources(),
98 vm.doCompile(fixedNames.addAndNew(both));
101 private void doCompile(StringArray names) throws IOException {
104 "\n var invoker = {};");
106 append(invokerMethods);
108 for (String r : asBinary.toArray()) {
109 append("\n ").append(getExportsObject()).append("['registerResource']('");
110 append(r).append("', '");
111 InputStream is = this.resources.get(r);
112 byte[] arr = new byte[is.available()];
115 if (offset == arr.length) {
116 byte[] tmp = new byte[arr.length * 2];
117 System.arraycopy(arr, 0, tmp, 0, arr.length);
120 int len = is.read(arr, offset, arr.length - offset);
126 if (offset != arr.length) {
127 byte[] tmp = new byte[offset];
128 System.arraycopy(arr, 0, tmp, 0, offset);
139 @JavaScriptBody(args = { "arr" }, body = "return btoa(arr);")
140 private static String btoa(byte[] arr) {
141 return javax.xml.bind.DatatypeConverter.printBase64Binary(arr);
144 protected abstract void generatePrologue() throws IOException;
146 protected abstract void generateEpilogue() throws IOException;
148 protected abstract String getExportsObject();
150 protected abstract boolean isExternalClass(String className);
152 protected abstract void lazyReference(Appendable out, String n) throws IOException;
155 protected final void declaredClass(ClassData classData, String mangledName)
157 if (exportedSymbols.isExported(classData)) {
158 append("\n").append(getExportsObject()).append("['")
161 .append(accessClass(mangledName))
167 protected String generateClass(String className) throws IOException {
168 ClassData classData = classDataCache.getClassData(className);
169 if (classData == null) {
170 throw new IOException("Can't find class " + className);
172 return compile(classData);
176 protected void declaredField(FieldData fieldData,
178 String mangledName) throws IOException {
179 if (exportedSymbols.isExported(fieldData)) {
180 exportMember(destObject, mangledName);
185 protected void declaredMethod(MethodData methodData,
187 String mangledName) throws IOException {
188 if (isHierarchyExported(methodData)) {
189 exportMember(destObject, mangledName);
193 private void exportMember(String destObject, String memberName)
195 append("\n").append(destObject).append("['")
197 .append("'] = m;\n");
200 private void generateBody(StringArray names) throws IOException {
201 StringArray processed = new StringArray();
202 StringArray initCode = new StringArray();
203 StringArray skipClass = new StringArray();
204 for (String baseClass : names.toArray()) {
205 references.add(baseClass);
208 for (String n : references.toArray()) {
209 if (skipClass.contains(n)) {
212 if (processed.contains(n)) {
220 InputStream is = resources.get(name + ".class");
222 lazyReference(this, name);
227 String ic = generateClass(name);
229 initCode.add(ic == null ? "" : ic);
230 } catch (RuntimeException ex) {
231 throw new IOException("Error while compiling " + name + "\n", ex);
235 for (String resource : scripts.toArray()) {
236 while (resource.startsWith("/")) {
237 resource = resource.substring(1);
239 requireResourceImpl(resource);
240 asBinary.remove(resource);
242 scripts = new StringArray();
244 StringArray toInit = StringArray.asList(references.toArray());
247 for (String ic : toInit.toArray()) {
248 int indx = processed.indexOf(ic);
250 final String theCode = initCode.toArray()[indx];
251 if (!theCode.isEmpty()) {
252 append(theCode).append("\n");
254 initCode.toArray()[indx] = "";
260 final void requireResourceImpl(String resource) throws IOException {
261 InputStream emul = resources.get(resource);
263 throw new IOException("Can't find " + resource);
265 append("\n// resource from ").append(resource).append("\n");
266 readResource(emul, this);
270 private static void readResource(InputStream emul, Appendable out) throws IOException {
274 int ch = emul.read();
278 if (ch < 0 || ch > 255) {
279 throw new IOException("Invalid char in emulation " + ch);
281 out.append((char)ch);
288 static String toString(String name) throws IOException {
289 StringBuilder sb = new StringBuilder();
290 // compile(sb, name);
291 return sb.toString().toString();
294 private StringArray scripts = new StringArray();
295 private StringArray references = new StringArray();
298 protected boolean requireReference(String cn) {
299 return references.addIfMissing(cn);
303 protected void requireScript(String resourcePath) {
304 scripts.add(resourcePath);
308 String assignClass(String className) {
309 return "vm." + className + " = ";
313 String accessClass(String className) {
314 return "vm." + className;
318 protected String accessField(String object, String mangledName,
319 String[] fieldInfoName) throws IOException {
320 final FieldData field =
321 classDataCache.findField(fieldInfoName[0],
324 return accessNonVirtualMember(object, mangledName,
325 (field != null) ? field.cls : null);
329 protected String accessStaticMethod(
332 String[] fieldInfoName) throws IOException {
333 final MethodData method =
334 classDataCache.findMethod(fieldInfoName[0],
337 return accessNonVirtualMember(object, mangledName,
338 (method != null) ? method.cls : null);
342 protected String accessVirtualMethod(
345 String[] fieldInfoName,
347 ) throws IOException {
348 final ClassData referencedClass =
349 classDataCache.getClassData(fieldInfoName[0]);
350 final MethodData method =
351 classDataCache.findMethod(referencedClass,
356 && !isExternalClass(method.cls.getClassName())
357 && (((method.access & ByteCodeParser.ACC_FINAL) != 0)
358 || ((referencedClass.getAccessFlags()
359 & ByteCodeParser.ACC_FINAL) != 0)
360 || !isHierarchyExported(method))) {
361 return object + "." + mangledName + '(';
364 return accessThroughInvoker(object, mangledName, params);
367 private String accessThroughInvoker(String object, String mangledName, int params)
369 String def = "\n invoker." + mangledName + " = function(target";
370 if (invokerMethods.indexOf(def) == -1) {
371 invokerMethods.append(def);
372 for (int j = 0; j < params; j++) {
373 invokerMethods.append(", p").append(j);
375 invokerMethods.append(") {\n return target['").
376 append(mangledName).append("'](");
377 for (int j = 0; j < params; j++) {
379 invokerMethods.append(",");
381 invokerMethods.append("p").append(j);
383 invokerMethods.append(");\n };");
385 return "invoker." + mangledName + '(' + object + (params > 1 ? "," : "");
388 private boolean isHierarchyExported(final MethodData methodData)
390 if (exportedSymbols.isExported(methodData)) {
393 if ((methodData.access & (ByteCodeParser.ACC_PRIVATE
394 | ByteCodeParser.ACC_STATIC)) != 0) {
398 final ExportedMethodFinder exportedMethodFinder =
399 new ExportedMethodFinder(exportedSymbols);
401 classDataCache.findMethods(
403 methodData.getName(),
404 methodData.getInternalSig(),
405 exportedMethodFinder);
407 return (exportedMethodFinder.getFound() != null);
410 private String accessNonVirtualMember(String object,
412 ClassData declaringClass) {
413 if (declaringClass == null) {
414 return object + "['" + mangledName + "']";
416 final String className = declaringClass.getClassName();
418 "java/lang/Object".equals(className) ||
419 "java/lang/reflect/Array".equals(className) ||
420 isExternalClass(className)
422 return object + "['" + mangledName + "']";
424 return object + "." + mangledName;
428 protected Flow checkFlow(MethodData byteCodes) throws IOException {
432 Flow f = new Flow(byteCodes, this);
433 return flow.analyze(f) ? f : null;
436 private final class ExportedMethodFinder
437 implements ClassDataCache.TraversalCallback<MethodData> {
438 private final ExportedSymbols exportedSymbols;
439 private MethodData found;
441 public ExportedMethodFinder(final ExportedSymbols exportedSymbols) {
442 this.exportedSymbols = exportedSymbols;
446 public boolean traverse(final MethodData methodData) {
449 exportedSymbols.isExported(methodData) ||
450 isExternalClass(methodData.cls.getClassName())
455 } catch (final IOException e) {
461 public MethodData getFound() {
466 private static final class Standalone extends VM {
467 private Standalone(Appendable out,
468 Bck2Brwsr.Resources resources,
469 StringArray explicitlyExported, StringArray asBinary,
472 super(out, resources, explicitlyExported, asBinary, flow);
476 protected void generatePrologue() throws IOException {
477 append("(function VM(global) {var fillInVMSkeleton = function(vm) {");
481 protected void generateEpilogue() throws IOException {
485 + " var extensions = [];\n"
486 + " function replaceAll(s, target, replacement) {\n"
489 + " var indx = s.indexOf(target, pos);\n"
490 + " if (indx === -1) {\n"
493 + " pos = indx + replacement.length;\n"
494 + " s = s.substring(0, indx) + replacement + s.substring(indx + target.length);\n"
497 + " function mangleClass(name) {\n"
498 + " name = replaceAll(name, '_', '_1');\n"
499 + " name = replaceAll(name, '.', '_');\n"
502 + " var pending = [];\n"
503 + " var pendingClasses = [];\n"
504 + " function extensionLoaded(ev) {\n"
505 + " var at = pending.indexOf(ev.target);\n"
506 + " pending.splice(at, 1);\n"
507 + " if (pending.length === 0) {\n"
508 + " for (var i = 0; i < pendingClasses.length; i += 3) {\n"
509 + " invokeMethod(pendingClasses[i], pendingClasses[i + 1], pendingClasses[i + 2]);\n"
511 + " pendingClasses = [];\n"
514 + " function invokeMethod(vm, n, args) {\n"
515 + " var clazz = vm.loadClass(n);\n"
517 + " var seek = args[0];\n"
518 + " var prefix = seek.indexOf('__') == -1 ? seek + '__' : seek;\n"
519 + " args = Array.prototype.slice.call(args, 1);\n"
520 + " var found = '';\n"
521 + " for (var m in clazz) {\n"
522 + " if (m.indexOf(prefix) === 0) {\n"
523 + " return clazz[m].apply(null, args);\n"
525 + " found += m.toString() + '\\n'\n"
527 + " throw 'Cannot find ' + seek + ' in ' + n + ' found:\\n' + found;\n"
530 + " function extensionError(ev) {\n"
531 + " console.log('error loading ' + ev.target.src);\n"
532 + " extensionLoaded(ev);\n"
534 + " function loadExtension(url) {\n"
535 + " if (url.substring(url.length - 4) == '.jar')\n"
536 + " url = url.substring(0, url.length - 4) + '.js';\n"
537 + " var script = document.createElement('script');\n"
538 + " script.type = 'text/javascript';\n"
539 + " script.src = url;\n"
540 + " script.onload = extensionLoaded;\n"
541 + " script.onerror = extensionError;\n"
542 + " document.getElementsByTagName('head')[0].appendChild(script);\n"
543 + " pending.push(script);\n"
545 + " global.bck2brwsr = function() {\n"
546 + " var args = Array.prototype.slice.apply(arguments);\n"
547 + " var resources = {};\n"
548 + " function registerResource(n, a64) {\n"
549 + " var frm = atob || window.atob;\n"
550 + " var str = frm(a64);\n"
552 + " for (var i = 0; i < str.length; i++) {\n"
553 + " var ch = str.charCodeAt(i) & 0xff;\n"
554 + " if (ch > 127) ch -= 256;\n"
557 + " if (!resources[n]) resources[n] = [arr];\n"
558 + " else resources[n].push(arr);\n"
560 + " var vm = fillInVMSkeleton({ 'registerResource' : registerResource });\n"
561 + " function initVM() {\n"
562 + " var clsArray = vm['java_lang_reflect_Array'];\n"
563 + " if (clsArray) clsArray(false);\n"
565 + " for (var i = 0; i < extensions.length; ++i) {\n"
566 + " extensions[i](vm);\n"
568 + " vm['registerResource'] = null;\n"
569 + " var knownExtensions = extensions.length;\n"
570 + " var loader = {};\n"
571 + " var loadBytes = function(name, skip) {\n"
572 + " skip = typeof skip == 'number' ? skip : 0;\n"
573 + " var arr = resources[name];\n"
575 + " var arrSize = arr.length;\n"
576 + " if (skip < arrSize) return arr[skip];\n"
577 + " skip -= arrSize;\n"
579 + " var arrSize = 0;\n"
581 + " for (var i = 0; i < args.length; i++) {\n"
582 + " var at = args[i];\n"
583 + " if(!at) continue;\n"
585 + " if (typeof at === 'string' && at.substring(at.length - 3) === '.js') {\n"
586 + " loadExtension(at);\n"
587 + " args[i] = null;\n"
588 + " } else if (typeof at === 'function') ret = at(name, skip);\n"
590 + " var cp = vm['org_apidesign_vm4brwsr_ClassPath'];\n"
591 + " if (!cp) throw 'Core Java library not registered. Cannot load from ' + at;\n"
592 + " ret = cp(false).\n"
593 + " loadBytes___3BLjava_lang_String_2Ljava_lang_Object_2II(name, args, i, skip);\n"
595 + " if (ret) return ret;\n"
597 + " while (knownExtensions < extensions.length) {\n"
598 + " vm['registerResource'] = registerResource;\n"
599 + " extensions[knownExtensions++](vm);\n"
600 + " vm['registerResource'] = null;\n"
603 + " var arr = resources[name];\n"
604 + " return (arr && arr.length > arrSize) ? arr[arrSize] : null;\n"
606 + " var reload = function(name, arr, keep) {\n"
607 + " if (!arr) throw 'Cannot find ' + name;\n"
608 + " var lazy = vm['org_apidesign_vm4brwsr_VMLazy'];\n"
609 + " if (!lazy) throw 'No bck2brwsr VM module to compile ' + name;\n"
611 + " var attr = mangleClass(name);\n"
612 + " delete vm[attr];\n"
614 + " return lazy(false)\n"
615 + " ['load__Ljava_lang_Object_2Ljava_lang_Object_2Ljava_lang_String_2_3Ljava_lang_Object_2_3B']\n"
616 + " (vm, name, args, arr);\n"
618 + " var loadClass = function(name) {\n"
619 + " var attr = mangleClass(name);\n"
620 + " var fn = vm[attr];\n"
621 + " if (fn) return fn(false);\n"
623 + " var arr = loadBytes(replaceAll(name, '.', '/') + '.class');\n"
624 + " return reload(name, arr, true);\n"
625 + " } catch (err) {\n"
626 + " fn = vm[attr];\n"
627 + " if (fn) return fn(false);\n"
631 + " if (vm['loadClass']) {\n"
632 + " throw 'Cannot initialize the bck2brwsr VM twice!';\n"
634 + " vm['loadClass'] = loadClass;\n"
635 + " vm['_reload'] = reload;\n"
636 + " vm['loadBytes'] = loadBytes;\n"
638 + " loader.loadClass = function(name) {\n"
639 + " if (pending.length === 0) {\n"
641 + " var c = loadClass(name);\n"
642 + " c['invoke'] = function() {\n"
643 + " return invokeMethod(vm, name, arguments);\n"
646 + " } catch (err) {\n"
647 + " if (pending.length === 0) throw err;\n"
650 + " pendingClasses.push(vm);\n"
651 + " pendingClasses.push(name);\n"
652 + " pendingClasses.push(null);\n"
654 + " 'invoke' : function() {\n"
655 + " if (pending.length === 0) {\n"
656 + " invokeMethod(vm, name, arguments);\n"
659 + " pendingClasses.push(vm);\n"
660 + " pendingClasses.push(name);\n"
661 + " pendingClasses.push(arguments);\n"
665 + " return loader;\n"
668 " global.bck2brwsr.register = function(config, extension) {\n"
669 + " if (!config || config['magic'] !== 'kafíčko') {\n"
670 + " console.log('Will not register: ' + extension);\n"
673 + " extensions.push(extension);\n"
674 + " var cp = config['classpath'];\n"
675 + " if (cp) for (var i = 0; i < cp.length; i++) {\n"
676 + " loadExtension(cp[i]);\n"
684 protected String getExportsObject() {
689 protected boolean isExternalClass(String className) {
694 protected void lazyReference(Appendable out, String n) throws IOException {
695 String cls = n.replace('/', '_');
696 String dot = n.replace('/', '.');
698 out.append("\nvm.").append(cls).append(" = function() {");
699 out.append("\n var instance = arguments.length == 0 || arguments[0] === true;");
700 out.append("\n delete vm.").append(cls).append(";");
701 out.append("\n var c = vm.loadClass('").append(dot).append("');");
702 out.append("\n return vm.").append(cls).append("(instance);");
707 protected void requireResource(String resourcePath) throws IOException {
708 requireResourceImpl(resourcePath);
712 private static final class Extension extends VM {
713 private final StringArray extensionClasses;
714 private final StringArray classpath;
716 private Extension(Appendable out, Bck2Brwsr.Resources resources,
717 String[] extClassesArray, StringArray explicitlyExported,
718 StringArray asBinary, StringArray classpath, Flow.Analyzer flow
719 ) throws IOException {
720 super(out, resources, explicitlyExported, asBinary, flow);
721 this.extensionClasses = StringArray.asList(extClassesArray);
722 this.classpath = classpath;
726 protected void generatePrologue() throws IOException {
728 "bck2brwsr.register({\n"
729 + " 'magic' : 'kafíčko'"
731 if (classpath != null && classpath.toArray().length > 0) {
733 ",\n 'classpath' : [\n"
736 for (String s : classpath.toArray()) {
737 append(sep).append("'").append(s).append("'");
745 "\n}, function(exports) {\n"
746 + " var vm = {};\n");
747 append(" function link(n, assign) {\n"
748 + " return function() {\n"
749 + " var cls = n['replace__Ljava_lang_String_2CC']"
750 + "('/', '_').toString();\n"
751 + " var dot = n['replace__Ljava_lang_String_2CC']"
752 + "('/', '.').toString();\n"
753 + " exports.loadClass(dot);\n"
754 + " assign(exports[cls]);\n"
755 + " return exports[cls](arguments);\n"
762 protected void generateEpilogue() throws IOException {
764 if (exportedCount == 0) {
765 throw new IOException("Creating library without any exported symbols is useless!");
770 protected String generateClass(String className) throws IOException {
771 if (isExternalClass(className)) {
772 final String cls = className.replace('/', '_');
773 append("\n").append(assignClass(cls))
776 .append("', function(f) { ").append(assignClass(cls)).append(" f; });");
781 return super.generateClass(className);
785 protected String getExportsObject() {
790 protected boolean isExternalClass(String className) {
791 return !extensionClasses.contains(className);
795 protected void lazyReference(Appendable out, String n) throws IOException {
796 String cls = n.replace('/', '_');
798 out.append("\nvm.").append(cls).append(" = function() {");
799 out.append("\n var instance = arguments.length == 0 || arguments[0] === true;");
800 out.append("\n delete vm.").append(cls).append(";");
801 out.append("\n return link('").append(n).append("', function(f) { vm.");
802 out.append(cls).append(" = f;})(instance);");
807 protected void requireResource(String resourcePath) throws IOException {
808 requireResourceImpl(resourcePath);