# HG changeset patch
# User Jaroslav Tulach <jaroslav.tulach@apidesign.org>
# Date 1346036910 -7200
# Node ID 71aab30ab2b784581c116e5a6ca24ddc986c377a

Initial version of the Bytecode to JavaScript translator

diff -r 000000000000 -r 71aab30ab2b7 pom.xml
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pom.xml	Mon Aug 27 05:08:30 2012 +0200
@@ -0,0 +1,86 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>org.apidesign</groupId>
+  <artifactId>java4browser</artifactId>
+  <version>0.1-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <name>java4browser</name>
+  <url>http://java4browser.apidesign.org</url>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <author.name>Jaroslav Tulach</author.name>
+    <author.email>jaroslav.tulach@apidesign.org</author.email>
+  </properties>
+  
+  <repositories>
+      <repository>
+          <id>netbeans</id>
+          <name>NetBeans</name>
+          <url>http://bits.netbeans.org/maven2/</url>
+      </repository>
+  </repositories>
+  <pluginRepositories>
+    <pluginRepository>
+        <id>mc-release</id>
+        <name>Local Maven repository of releases</name>
+        <url>http://mc-repo.googlecode.com/svn/maven2/releases</url>
+        <snapshots>
+            <enabled>false</enabled>
+        </snapshots>
+        <releases>
+            <enabled>true</enabled>
+        </releases>
+    </pluginRepository>
+  </pluginRepositories>
+  <scm>
+      <connection>scm:hg:http://source.apidesign.org/hg/quoridor</connection>
+      <url>http://source.apidesign.org/hg/quoridor</url>
+  </scm>
+  <licenses>
+    <license>
+        <name>GPL-2.0</name>
+        <url>http://opensource.org/licenses/GPL-2.0</url>
+        <distribution>repo</distribution>
+    </license>
+  </licenses>
+  <organization>
+      <name>API Design</name>
+      <url>http://apidesign.org</url>
+  </organization>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>com.mycila.maven-license-plugin</groupId>
+                <artifactId>maven-license-plugin</artifactId>
+                <version>1.9.0</version>
+                <configuration>
+                    <header>src/header.txt</header>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+  <dependencies>
+    <dependency>
+      <groupId>org.testng</groupId>
+      <artifactId>testng</artifactId>
+      <version>6.7</version>
+      <scope>test</scope>
+      <exclusions>
+        <exclusion>
+          <artifactId>junit</artifactId>
+          <groupId>junit</groupId>
+        </exclusion>
+      </exclusions>
+    </dependency>
+    <dependency>
+      <groupId>org.netbeans.api</groupId>
+      <artifactId>org-netbeans-modules-classfile</artifactId>
+      <version>RELEASE72</version>
+      <type>jar</type>
+    </dependency>
+  </dependencies>
+</project>
diff -r 000000000000 -r 71aab30ab2b7 src/header.txt
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/header.txt	Mon Aug 27 05:08:30 2012 +0200
@@ -0,0 +1,15 @@
+Java 4 Browser Bytecode Translator
+Copyright (C) 2012-${year} Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, version 2 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. Look for COPYING file in the top folder.
+If not, see http://opensource.org/licenses/GPL-2.0.
diff -r 000000000000 -r 71aab30ab2b7 src/main/java/org/apidesign/java4browser/ByteCodeToJavaScript.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/org/apidesign/java4browser/ByteCodeToJavaScript.java	Mon Aug 27 05:08:30 2012 +0200
@@ -0,0 +1,121 @@
+/*
+Java 4 Browser Bytecode Translator
+Copyright (C) 2012-2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, version 2 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. Look for COPYING file in the top folder.
+If not, see http://opensource.org/licenses/GPL-2.0.
+*/
+package org.apidesign.java4browser;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+import org.netbeans.modules.classfile.ByteCodes;
+import org.netbeans.modules.classfile.ClassFile;
+import org.netbeans.modules.classfile.Code;
+import org.netbeans.modules.classfile.Method;
+import org.netbeans.modules.classfile.Parameter;
+
+/** Translator of the code inside class files to JavaScript.
+ *
+ * @author Jaroslav Tulach <jtulach@netbeans.org>
+ */
+public final class ByteCodeToJavaScript {
+    private final ClassFile jc;
+    private final Appendable out;
+
+    private ByteCodeToJavaScript(ClassFile jc, Appendable out) {
+        this.jc = jc;
+        this.out = out;
+    }
+    
+    /** Converts a given class file to a JavaScript version.
+     * @param fileName the name of the file we are reading
+     * @param classFile input stream with code of the .class file
+     * @param out a {@link StringBuilder} or similar to generate the output to
+     * @throws IOException if something goes wrong during read or write or translating
+     */
+    public static void compile(String fileName, InputStream classFile, Appendable out) throws IOException {
+        ClassFile jc = new ClassFile(classFile, true);
+        ByteCodeToJavaScript compiler = new ByteCodeToJavaScript(jc, out);
+        for (Method m : jc.getMethods()) {
+            if (m.isStatic()) {
+                compiler.generateStaticMethod(m);
+            }
+        }
+    }
+    private void generateStaticMethod(Method m) throws IOException {
+        out.append("function ").append(
+            jc.getName().getExternalName().replace('.', '_')
+        ).append('_').append(
+            m.getName()
+        );
+        out.append(m.getReturnType());
+        List<Parameter> args = m.getParameters();
+        for (Parameter t : args) {
+            out.append(t.getDescriptor());
+        }
+        out.append('(');
+        String space = "";
+        for (int i = 0; i < args.size(); i++) {
+            out.append(space);
+            out.append("arg").append(String.valueOf(i));
+            space = ",";
+        }
+        out.append(") {").append("\n  var ");
+        final Code code = m.getCode();
+        int len = code.getMaxLocals();
+        space = "";
+        for (int i = 0; i < len; i++) {
+            out.append(space);
+            out.append("var").append(String.valueOf(i));
+            space = ",";
+        }
+        out.append(";\n  var stack = new Array(");
+        out.append(Integer.toString(code.getMaxStack()));
+        out.append(");\n");
+        produceCode(code.getByteCodes());
+        out.append(";\nreturn 1;");
+        out.append("}");
+    }
+
+    private void produceCode(byte[] byteCodes) throws IOException {
+        for (int i = 0; i < byteCodes.length; i++) {
+            int prev = i;
+            out.append("  ");
+            final int c = (byteCodes[i] + 256) % 256;
+            switch (c) {
+                case ByteCodes.bc_aload_0:
+                case ByteCodes.bc_iload_0:
+                    out.append("stack.push(arg0);");
+                    break;
+                case ByteCodes.bc_aload_1:
+                case ByteCodes.bc_iload_1:
+                    out.append("stack.push(arg1);");
+                    break;
+                case ByteCodes.bc_iadd:
+                    out.append("stack.push(stack.pop() + stack.pop());");
+                    break;
+                case ByteCodes.bc_ireturn:
+                    out.append("return stack.pop();");
+            }
+            out.append("/*");
+            for (int j = prev; j <= i; j++) {
+                out.append(" ");
+                final int cc = (byteCodes[j] + 256) % 256;
+                out.append(Integer.toString(cc));
+            }
+            out.append("*/\n");
+        }
+    }
+}
diff -r 000000000000 -r 71aab30ab2b7 src/test/java/org/apidesign/java4browser/StaticMethod.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/test/java/org/apidesign/java4browser/StaticMethod.java	Mon Aug 27 05:08:30 2012 +0200
@@ -0,0 +1,28 @@
+/*
+Java 4 Browser Bytecode Translator
+Copyright (C) 2012-2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, version 2 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. Look for COPYING file in the top folder.
+If not, see http://opensource.org/licenses/GPL-2.0.
+*/
+package org.apidesign.java4browser;
+
+/**
+ *
+ * @author Jaroslav Tulach <jtulach@netbeans.org>
+ */
+public class StaticMethod {
+    public static int sum(int x, int y) {
+        return x + y;
+    }
+}
diff -r 000000000000 -r 71aab30ab2b7 src/test/java/org/apidesign/java4browser/StaticMethodTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/test/java/org/apidesign/java4browser/StaticMethodTest.java	Mon Aug 27 05:08:30 2012 +0200
@@ -0,0 +1,57 @@
+/*
+Java 4 Browser Bytecode Translator
+Copyright (C) 2012-2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, version 2 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. Look for COPYING file in the top folder.
+If not, see http://opensource.org/licenses/GPL-2.0.
+*/
+package org.apidesign.java4browser;
+
+import java.io.IOException;
+import java.io.InputStream;
+import javax.script.Invocable;
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+import javax.script.ScriptException;
+import static org.testng.Assert.*;
+import org.testng.annotations.Test;
+
+/** Checks the basic behavior of the translator.
+ *
+ * @author Jaroslav Tulach <jtulach@netbeans.org>
+ */
+public class StaticMethodTest {
+    @Test public void threePlusFour() throws Exception {
+        Invocable i = compileClass("StaticMethod.class");
+        
+        Object ret = i.invokeFunction("org_apidesign_java4browser_StaticMethod_sumIII", 3, 4);
+        assertEquals(ret, Double.valueOf(7), "Should be seven");
+    }
+
+    static Invocable compileClass(String name) throws ScriptException, IOException {
+        InputStream is = StaticMethodTest.class.getResourceAsStream(name);
+        assertNotNull(is, "Class file found");
+        StringBuilder sb = new StringBuilder();
+        ByteCodeToJavaScript.compile(name, is, sb);
+        ScriptEngineManager sem = new ScriptEngineManager();
+        ScriptEngine js = sem.getEngineByExtension("js");
+        try {
+            Object res = js.eval(sb.toString());
+            assertTrue(js instanceof Invocable, "It is invocable object: " + res);
+            return (Invocable)js;
+        } catch (ScriptException ex) {
+            fail("Could not compile:\n" + sb, ex);
+            return null;
+        }
+    }
+}