jaroslav@170: /**
jaroslav@170:  * Back 2 Browser Bytecode Translator
jaroslav@170:  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
jaroslav@170:  *
jaroslav@170:  * This program is free software: you can redistribute it and/or modify
jaroslav@170:  * it under the terms of the GNU General Public License as published by
jaroslav@170:  * the Free Software Foundation, version 2 of the License.
jaroslav@170:  *
jaroslav@170:  * This program is distributed in the hope that it will be useful,
jaroslav@170:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
jaroslav@170:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
jaroslav@170:  * GNU General Public License for more details.
jaroslav@170:  *
jaroslav@170:  * You should have received a copy of the GNU General Public License
jaroslav@170:  * along with this program. Look for COPYING file in the top folder.
jaroslav@170:  * If not, see http://opensource.org/licenses/GPL-2.0.
jaroslav@170:  */
jaroslav@170: package org.apidesign.vm4brwsr;
jaroslav@170: 
jaroslav@170: import java.io.ByteArrayInputStream;
jaroslav@170: import java.io.IOException;
jaroslav@214: import org.apidesign.bck2brwsr.core.JavaScriptBody;
jaroslav@170: 
jaroslav@170: /**
jaroslav@170:  *
jaroslav@170:  * @author Jaroslav Tulach <jtulach@netbeans.org>
jaroslav@170:  */
jaroslav@278: final class VMLazy {
jaroslav@277:     private final Object loader;
jaroslav@278:     private final Object[] args;
jaroslav@214:     
jaroslav@278:     private VMLazy(Object loader, Object[] args) {
jaroslav@277:         this.loader = loader;
jaroslav@278:         this.args = args;
jaroslav@170:     }
jaroslav@170:     
jaroslav@277:     static void init() {
jaroslav@277:     }
jaroslav@277:     
jaroslav@278:     @JavaScriptBody(args={"l", "res", "args" }, body = ""
jaroslav@299:         + "\ntry {"
jaroslav@299:         + "\n  return args[0](res.toString());"
jaroslav@299:         + "\n} catch (x) {"
jaroslav@299:         + "\n  throw Object.getOwnPropertyNames(l.vm).toString() + x.toString();"
jaroslav@299:         + "\n}")
jaroslav@278:     private static native byte[] read(Object l, String res, Object[] args);
jaroslav@277:     
jaroslav@277:     static Object load(Object loader, String name, Object[] arguments) 
jaroslav@277:     throws IOException, ClassNotFoundException {
jaroslav@278:         return new VMLazy(loader, arguments).load(name);
jaroslav@278:     }
jaroslav@278:     
jaroslav@278:     private Object load(String name)
jaroslav@278:     throws IOException, ClassNotFoundException {
jaroslav@277:         String res = name.replace('.', '/') + ".class";
jaroslav@278:         byte[] arr = read(loader, res, args);
jaroslav@277:         if (arr == null) {
jaroslav@277:             throw new ClassNotFoundException(name);
jaroslav@277:         }
jaroslav@278: //        beingDefined(loader, name);
jaroslav@278:         StringBuilder out = new StringBuilder();
jaroslav@278:         out.append("var loader = arguments[0];\n");
jaroslav@278:         out.append("var vm = loader.vm;\n");
jaroslav@278:         new Gen(this, out).compile(new ByteArrayInputStream(arr));
jaroslav@278:         String code = out.toString().toString();
jaroslav@278:         String under = name.replace('.', '_');
jaroslav@278:         return applyCode(loader, under, code);
jaroslav@277:     }
jaroslav@278: 
jaroslav@278: /* possibly not needed:
jaroslav@278:     @JavaScriptBody(args = {"loader", "n" }, body =
jaroslav@278:         "var cls = n.replace__Ljava_lang_String_2CC(n, '.','_').toString();" +
jaroslav@278:         "loader.vm[cls] = true;\n"
jaroslav@278:     )
jaroslav@278:     private static native void beingDefined(Object loader, String name);
jaroslav@278: */
jaroslav@277:     
jaroslav@278: 
jaroslav@277:     @JavaScriptBody(args = {"loader", "name", "script" }, body =
jaroslav@277:         "try {\n" +
jaroslav@277:         "  new Function(script)(loader, name);\n" +
jaroslav@277:         "} catch (ex) {\n" +
jaroslav@301:         "  throw 'Cannot compile ' + ex + ' line: ' + ex.lineNumber + ' script:\\n' + script;\n" +
jaroslav@277:         "}\n" +
jaroslav@277:         "return vm[name](false);\n"
jaroslav@277:     )
jaroslav@277:     private static native Object applyCode(Object loader, String name, String script);
jaroslav@277:     
jaroslav@278:     
jaroslav@278:     private static final class Gen extends ByteCodeToJavaScript {
jaroslav@278:         private final VMLazy lazy;
jaroslav@170: 
jaroslav@278:         public Gen(VMLazy vm, Appendable out) {
jaroslav@278:             super(out);
jaroslav@278:             this.lazy = vm;
jaroslav@278:         }
jaroslav@278:         
jaroslav@278:         @JavaScriptBody(args = {"self", "n"},
jaroslav@278:         body =
jaroslav@278:         "var cls = n.replace__Ljava_lang_String_2CC(n, '/','_').toString();"
jaroslav@278:         + "\nvar dot = n.replace__Ljava_lang_String_2CC(n,'/','.').toString();"
jaroslav@278:         + "\nvar lazy = self.fld_lazy;"
jaroslav@278:         + "\nvar loader = lazy.fld_loader;"
jaroslav@278:         + "\nvar vm = loader.vm;"
jaroslav@278:         + "\nif (vm[cls]) return false;"
jaroslav@278:         + "\nvm[cls] = function() {"
jaroslav@278:         + "\n  return lazy.load__Ljava_lang_Object_2Ljava_lang_String_2(lazy, dot);"
jaroslav@278:         + "\n};"
jaroslav@278:         + "\nreturn true;")
jaroslav@278:         @Override
jaroslav@278:         protected boolean requireReference(String internalClassName) {
jaroslav@278:             throw new UnsupportedOperationException();
jaroslav@278:         }
jaroslav@170: 
jaroslav@278:         @Override
jaroslav@278:         protected void requireScript(String resourcePath) {
jaroslav@278:         }
jaroslav@213: 
jaroslav@278:         @Override
jaroslav@278:         String assignClass(String className) {
jaroslav@278:             return "vm[arguments[1]]=";
jaroslav@278:         }
jaroslav@277: 
jaroslav@278:         @Override
jaroslav@278:         String accessClass(String classOperation) {
jaroslav@278:             return "vm." + classOperation;
jaroslav@278:         }
jaroslav@213:     }
jaroslav@170: }