1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/vm/src/main/java/org/apidesign/vm4brwsr/VMLazy.java	Fri Dec 07 06:29:54 2012 +0100
     1.3 @@ -0,0 +1,100 @@
     1.4 +/**
     1.5 + * Back 2 Browser Bytecode Translator
     1.6 + * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
     1.7 + *
     1.8 + * This program is free software: you can redistribute it and/or modify
     1.9 + * it under the terms of the GNU General Public License as published by
    1.10 + * the Free Software Foundation, version 2 of the License.
    1.11 + *
    1.12 + * This program is distributed in the hope that it will be useful,
    1.13 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.14 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.15 + * GNU General Public License for more details.
    1.16 + *
    1.17 + * You should have received a copy of the GNU General Public License
    1.18 + * along with this program. Look for COPYING file in the top folder.
    1.19 + * If not, see http://opensource.org/licenses/GPL-2.0.
    1.20 + */
    1.21 +package org.apidesign.vm4brwsr;
    1.22 +
    1.23 +import java.io.ByteArrayInputStream;
    1.24 +import java.io.IOException;
    1.25 +import org.apidesign.bck2brwsr.core.JavaScriptBody;
    1.26 +
    1.27 +/**
    1.28 + *
    1.29 + * @author Jaroslav Tulach <jtulach@netbeans.org>
    1.30 + */
    1.31 +class VMLazy extends ByteCodeToJavaScript {
    1.32 +    private final Object loader;
    1.33 +    
    1.34 +    private VMLazy(Object loader, Appendable out) {
    1.35 +        super(out);
    1.36 +        this.loader = loader;
    1.37 +    }
    1.38 +    
    1.39 +    static void init() {
    1.40 +    }
    1.41 +    
    1.42 +    @JavaScriptBody(args={"res", "args" }, body = "return args[0](res.toString());")
    1.43 +    private static native byte[] read(String res, Object[] args);
    1.44 +    
    1.45 +    static Object load(Object loader, String name, Object[] arguments) 
    1.46 +    throws IOException, ClassNotFoundException {
    1.47 +        String res = name.replace('.', '/') + ".class";
    1.48 +        byte[] arr = read(res, arguments);
    1.49 +        if (arr == null) {
    1.50 +            throw new ClassNotFoundException(name);
    1.51 +        }
    1.52 +        String code = toJavaScript(loader, arr);
    1.53 +        return applyCode(loader, name, code);
    1.54 +    }
    1.55 +    
    1.56 +    @JavaScriptBody(args = {"loader", "name", "script" }, body =
    1.57 +        "try {\n" +
    1.58 +        "  new Function(script)(loader, name);\n" +
    1.59 +        "} catch (ex) {\n" +
    1.60 +        "  throw 'Cannot compile ' + ex + ' script:\\\\n' + script;\n" +
    1.61 +        "}\n" +
    1.62 +        "return vm[name](false);\n"
    1.63 +    )
    1.64 +    private static native Object applyCode(Object loader, String name, String script);
    1.65 +    
    1.66 +    private static String toJavaScript(Object loader, byte[] is) throws IOException {
    1.67 +        StringBuilder sb = new StringBuilder();
    1.68 +        sb.append("var loader = arguments[0];\n");
    1.69 +        sb.append("var vm = loader.vm;\n");
    1.70 +        new VMLazy(loader, sb).compile(new ByteArrayInputStream(is));
    1.71 +        return sb.toString().toString();
    1.72 +    }
    1.73 +
    1.74 +    @JavaScriptBody(args = { "self", "n" }, 
    1.75 +        body=
    1.76 +          "var cls = n.replace__Ljava_lang_String_2CC(n,'/','_').toString();"
    1.77 +        + "var loader = self.fld_loader;"
    1.78 +        + "var vm = loader.vm;"
    1.79 +        + "if (vm[cls]) return false;"
    1.80 +        + "vm[cls] = function() {"
    1.81 +        + "  return loader.loadClass(n,cls);"
    1.82 +        + "};"
    1.83 +        + "return true;"
    1.84 +    )
    1.85 +    @Override
    1.86 +    protected boolean requireReference(String internalClassName) {
    1.87 +        throw new UnsupportedOperationException();
    1.88 +    }
    1.89 +
    1.90 +    @Override
    1.91 +    protected void requireScript(String resourcePath) {
    1.92 +    }
    1.93 +
    1.94 +    @Override
    1.95 +    String assignClass(String className) {
    1.96 +        return "vm[arguments[1]]=";
    1.97 +    }
    1.98 +
    1.99 +    @Override
   1.100 +    String accessClass(String classOperation) {
   1.101 +        return "vm." + classOperation;
   1.102 +    }
   1.103 +}