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@201: class VMLazy extends ByteCodeToJavaScript {
jaroslav@277:     private final Object loader;
jaroslav@214:     
jaroslav@277:     private VMLazy(Object loader, Appendable out) {
jaroslav@170:         super(out);
jaroslav@277:         this.loader = loader;
jaroslav@170:     }
jaroslav@170:     
jaroslav@277:     static void init() {
jaroslav@277:     }
jaroslav@277:     
jaroslav@277:     @JavaScriptBody(args={"res", "args" }, body = "return args[0](res.toString());")
jaroslav@277:     private static native byte[] read(String res, Object[] args);
jaroslav@277:     
jaroslav@277:     static Object load(Object loader, String name, Object[] arguments) 
jaroslav@277:     throws IOException, ClassNotFoundException {
jaroslav@277:         String res = name.replace('.', '/') + ".class";
jaroslav@277:         byte[] arr = read(res, arguments);
jaroslav@277:         if (arr == null) {
jaroslav@277:             throw new ClassNotFoundException(name);
jaroslav@277:         }
jaroslav@277:         String code = toJavaScript(loader, arr);
jaroslav@277:         return applyCode(loader, name, code);
jaroslav@277:     }
jaroslav@277:     
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@277:         "  throw 'Cannot compile ' + ex + ' 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@277:     private static String toJavaScript(Object loader, byte[] is) throws IOException {
jaroslav@170:         StringBuilder sb = new StringBuilder();
jaroslav@277:         sb.append("var loader = arguments[0];\n");
jaroslav@277:         sb.append("var vm = loader.vm;\n");
jaroslav@277:         new VMLazy(loader, sb).compile(new ByteArrayInputStream(is));
jaroslav@170:         return sb.toString().toString();
jaroslav@170:     }
jaroslav@170: 
jaroslav@214:     @JavaScriptBody(args = { "self", "n" }, 
jaroslav@214:         body=
jaroslav@248:           "var cls = n.replace__Ljava_lang_String_2CC(n,'/','_').toString();"
jaroslav@277:         + "var loader = self.fld_loader;"
jaroslav@277:         + "var vm = loader.vm;"
jaroslav@277:         + "if (vm[cls]) return false;"
jaroslav@277:         + "vm[cls] = function() {"
jaroslav@277:         + "  return loader.loadClass(n,cls);"
jaroslav@214:         + "};"
jaroslav@214:         + "return true;"
jaroslav@214:     )
jaroslav@170:     @Override
jaroslav@170:     protected boolean requireReference(String internalClassName) {
jaroslav@214:         throw new UnsupportedOperationException();
jaroslav@170:     }
jaroslav@170: 
jaroslav@170:     @Override
jaroslav@170:     protected void requireScript(String resourcePath) {
jaroslav@170:     }
jaroslav@213: 
jaroslav@213:     @Override
jaroslav@277:     String assignClass(String className) {
jaroslav@277:         return "vm[arguments[1]]=";
jaroslav@277:     }
jaroslav@277: 
jaroslav@277:     @Override
jaroslav@277:     String accessClass(String classOperation) {
jaroslav@277:         return "vm." + classOperation;
jaroslav@213:     }
jaroslav@170: }