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/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.javascript;
import org.mozilla.classfile.*;
import java.lang.reflect.*;
import java.io.*;
import java.security.*;
import java.util.*;
public final class JavaAdapter implements IdFunctionCall
{
/**
* Provides a key with which to distinguish previously generated
* adapter classes stored in a hash table.
*/
static class JavaAdapterSignature
{
Class superClass;
Class[] interfaces;
ObjToIntMap names;
JavaAdapterSignature(Class superClass, Class[] interfaces,
ObjToIntMap names)
{
this.superClass = superClass;
this.interfaces = interfaces;
this.names = names;
}
@Override
public boolean equals(Object obj)
{
if (!(obj instanceof JavaAdapterSignature))
return false;
JavaAdapterSignature sig = (JavaAdapterSignature) obj;
if (superClass != sig.superClass)
return false;
if (interfaces != sig.interfaces) {
if (interfaces.length != sig.interfaces.length)
return false;
for (int i=0; i < interfaces.length; i++)
if (interfaces[i] != sig.interfaces[i])
return false;
}
if (names.size() != sig.names.size())
return false;
ObjToIntMap.Iterator iter = new ObjToIntMap.Iterator(names);
for (iter.start(); !iter.done(); iter.next()) {
String name = (String)iter.getKey();
int arity = iter.getValue();
if (arity != sig.names.get(name, arity + 1))
return false;
}
return true;
}
@Override
public int hashCode()
{
return (superClass.hashCode() + Arrays.hashCode(interfaces)) ^ names.size();
}
}
public static void init(Context cx, Scriptable scope, boolean sealed)
{
JavaAdapter obj = new JavaAdapter();
IdFunctionObject ctor = new IdFunctionObject(obj, FTAG, Id_JavaAdapter,
"JavaAdapter", 1, scope);
ctor.markAsConstructor(null);
if (sealed) {
ctor.sealObject();
}
ctor.exportAsScopeProperty();
}
public Object execIdCall(IdFunctionObject f, Context cx, Scriptable scope,
Scriptable thisObj, Object[] args)
{
if (f.hasTag(FTAG)) {
if (f.methodId() == Id_JavaAdapter) {
return js_createAdapter(cx, scope, args);
}
}
throw f.unknown();
}
public static Object convertResult(Object result, Class c)
{
if (result == Undefined.instance &&
(c != ScriptRuntime.ObjectClass &&
c != ScriptRuntime.StringClass))
{
// Avoid an error for an undefined value; return null instead.
return null;
}
return Context.jsToJava(result, c);
}
public static Scriptable createAdapterWrapper(Scriptable obj, Object adapter)
{
Scriptable scope = ScriptableObject.getTopLevelScope(obj);
NativeJavaObject res = new NativeJavaObject(scope, adapter, null, true);
res.setPrototype(obj);
return res;
}
public static Object getAdapterSelf(Class adapterClass, Object adapter)
throws NoSuchFieldException, IllegalAccessException
{
Field self = adapterClass.getDeclaredField("self");
return self.get(adapter);
}
static Object js_createAdapter(Context cx, Scriptable scope, Object[] args)
{
int N = args.length;
if (N == 0) {
throw ScriptRuntime.typeError0("msg.adapter.zero.args");
}
// Expected arguments:
// Any number of NativeJavaClass objects representing the super-class
// and/or interfaces to implement, followed by one NativeObject providing
// the implementation, followed by any number of arguments to pass on
// to the (super-class) constructor.
int classCount;
for (classCount = 0; classCount < N - 1; classCount++) {
Object arg = args[classCount];
// We explicitly test for NativeObject here since checking for
// instanceof ScriptableObject or !(instanceof NativeJavaClass)
// would fail for a Java class that isn't found in the class path
// as NativeJavaPackage extends ScriptableObject.
if (arg instanceof NativeObject) {
break;
}
if (!(arg instanceof NativeJavaClass)) {
throw ScriptRuntime.typeError2("msg.not.java.class.arg",
String.valueOf(classCount),
ScriptRuntime.toString(arg));
}
}
Class superClass = null;
Class[] intfs = new Class[classCount];
int interfaceCount = 0;
for (int i = 0; i < classCount; ++i) {
Class c = ((NativeJavaClass) args[i]).getClassObject();
if (!c.isInterface()) {
if (superClass != null) {
throw ScriptRuntime.typeError2("msg.only.one.super",
superClass.getName(), c.getName());
}
superClass = c;
} else {
intfs[interfaceCount++] = c;
}
}
if (superClass == null) {
superClass = ScriptRuntime.ObjectClass;
}
Class[] interfaces = new Class[interfaceCount];
System.arraycopy(intfs, 0, interfaces, 0, interfaceCount);
// next argument is implementation, must be scriptable
Scriptable obj = ScriptableObject.ensureScriptable(args[classCount]);
Class adapterClass = getAdapterClass(scope, superClass, interfaces, obj);
Object adapter;
int argsCount = N - classCount - 1;
try {
if (argsCount > 0) {
// Arguments contain parameters for super-class constructor.
// We use the generic Java method lookup logic to find and
// invoke the right constructor.
Object[] ctorArgs = new Object[argsCount + 2];
ctorArgs[0] = obj;
ctorArgs[1] = cx.getFactory();
System.arraycopy(args, classCount + 1, ctorArgs, 2, argsCount);
// TODO: cache class wrapper?
NativeJavaClass classWrapper = new NativeJavaClass(scope,
adapterClass, true);
NativeJavaMethod ctors = classWrapper.members.ctors;
int index = ctors.findCachedFunction(cx, ctorArgs);
if (index < 0) {
String sig = NativeJavaMethod.scriptSignature(args);
throw Context.reportRuntimeError2(
"msg.no.java.ctor", adapterClass.getName(), sig);
}
// Found the constructor, so try invoking it.
adapter = NativeJavaClass.constructInternal(ctorArgs, ctors.methods[index]);
} else {
Class[] ctorParms = {
ScriptRuntime.ScriptableClass,
ScriptRuntime.ContextFactoryClass
};
Object[] ctorArgs = { obj, cx.getFactory() };
adapter = adapterClass.getConstructor(ctorParms).newInstance(ctorArgs);
}
Object self = getAdapterSelf(adapterClass, adapter);
// Return unwrapped JavaAdapter if it implements Scriptable
if (self instanceof Wrapper) {
Object unwrapped = ((Wrapper) self).unwrap();
if (unwrapped instanceof Scriptable) {
if (unwrapped instanceof ScriptableObject) {
ScriptRuntime.setObjectProtoAndParent(
(ScriptableObject)unwrapped, scope);
}
return unwrapped;
}
}
return self;
} catch (Exception ex) {
throw Context.throwAsScriptRuntimeEx(ex);
}
}
// Needed by NativeJavaObject serializer
public static void writeAdapterObject(Object javaObject,
ObjectOutputStream out)
throws IOException
{
Class cl = javaObject.getClass();
out.writeObject(cl.getSuperclass().getName());
Class[] interfaces = cl.getInterfaces();
String[] interfaceNames = new String[interfaces.length];
for (int i=0; i < interfaces.length; i++)
interfaceNames[i] = interfaces[i].getName();
out.writeObject(interfaceNames);
try {
Object delegee = cl.getField("delegee").get(javaObject);
out.writeObject(delegee);
return;
} catch (IllegalAccessException e) {
} catch (NoSuchFieldException e) {
}
throw new IOException();
}
// Needed by NativeJavaObject de-serializer
public static Object readAdapterObject(Scriptable self,
ObjectInputStream in)
throws IOException, ClassNotFoundException
{
ContextFactory factory;
Context cx = Context.getCurrentContext();
if (cx != null) {
factory = cx.getFactory();
} else {
factory = null;
}
Class superClass = Class.forName((String)in.readObject());
String[] interfaceNames = (String[])in.readObject();
Class[] interfaces = new Class[interfaceNames.length];
for (int i=0; i < interfaceNames.length; i++)
interfaces[i] = Class.forName(interfaceNames[i]);
Scriptable delegee = (Scriptable)in.readObject();
Class adapterClass = getAdapterClass(self, superClass, interfaces,
delegee);
Class[] ctorParms = {
ScriptRuntime.ContextFactoryClass,
ScriptRuntime.ScriptableClass,
ScriptRuntime.ScriptableClass
};
Object[] ctorArgs = { factory, delegee, self };
try {
return adapterClass.getConstructor(ctorParms).newInstance(ctorArgs);
} catch(InstantiationException e) {
} catch(IllegalAccessException e) {
} catch(InvocationTargetException e) {
} catch(NoSuchMethodException e) {
}
throw new ClassNotFoundException("adapter");
}
private static ObjToIntMap getObjectFunctionNames(Scriptable obj)
{
Object[] ids = ScriptableObject.getPropertyIds(obj);
ObjToIntMap map = new ObjToIntMap(ids.length);
for (int i = 0; i != ids.length; ++i) {
if (!(ids[i] instanceof String))
continue;
String id = (String) ids[i];
Object value = ScriptableObject.getProperty(obj, id);
if (value instanceof Function) {
Function f = (Function)value;
int length = ScriptRuntime.toInt32(
ScriptableObject.getProperty(f, "length"));
if (length < 0) {
length = 0;
}
map.put(id, length);
}
}
return map;
}
private static Class getAdapterClass(Scriptable scope, Class superClass,
Class[] interfaces, Scriptable obj)
{
ClassCache cache = ClassCache.get(scope);
Map> generated
= cache.getInterfaceAdapterCacheMap();
ObjToIntMap names = getObjectFunctionNames(obj);
JavaAdapterSignature sig;
sig = new JavaAdapterSignature(superClass, interfaces, names);
Class adapterClass = generated.get(sig);
if (adapterClass == null) {
String adapterName = "adapter" + cache.newClassSerialNumber();
byte[] code = createAdapterCode(names, adapterName,
superClass, interfaces, null);
adapterClass = loadAdapterClass(adapterName, code);
if (cache.isCachingEnabled()) {
generated.put(sig, adapterClass);
}
}
return adapterClass;
}
public static byte[] createAdapterCode(ObjToIntMap functionNames,
String adapterName,
Class superClass,
Class[] interfaces,
String scriptClassName)
{
ClassFileWriter cfw = new ClassFileWriter(adapterName,
superClass.getName(),
"");
cfw.addField("factory", "Lorg/mozilla/javascript/ContextFactory;",
(short) (ClassFileWriter.ACC_PUBLIC |
ClassFileWriter.ACC_FINAL));
cfw.addField("delegee", "Lorg/mozilla/javascript/Scriptable;",
(short) (ClassFileWriter.ACC_PUBLIC |
ClassFileWriter.ACC_FINAL));
cfw.addField("self", "Lorg/mozilla/javascript/Scriptable;",
(short) (ClassFileWriter.ACC_PUBLIC |
ClassFileWriter.ACC_FINAL));
int interfacesCount = interfaces == null ? 0 : interfaces.length;
for (int i=0; i < interfacesCount; i++) {
if (interfaces[i] != null)
cfw.addInterface(interfaces[i].getName());
}
String superName = superClass.getName().replace('.', '/');
Constructor[] ctors = superClass.getDeclaredConstructors();
for (Constructor ctor : ctors) {
int mod = ctor.getModifiers();
if (Modifier.isPublic(mod) || Modifier.isProtected(mod)) {
generateCtor(cfw, adapterName, superName, ctor);
}
}
generateSerialCtor(cfw, adapterName, superName);
if (scriptClassName != null) {
generateEmptyCtor(cfw, adapterName, superName, scriptClassName);
}
ObjToIntMap generatedOverrides = new ObjToIntMap();
ObjToIntMap generatedMethods = new ObjToIntMap();
// generate methods to satisfy all specified interfaces.
for (int i = 0; i < interfacesCount; i++) {
Method[] methods = interfaces[i].getMethods();
for (int j = 0; j < methods.length; j++) {
Method method = methods[j];
int mods = method.getModifiers();
if (Modifier.isStatic(mods) || Modifier.isFinal(mods)) {
continue;
}
String methodName = method.getName();
Class[] argTypes = method.getParameterTypes();
if (!functionNames.has(methodName)) {
try {
superClass.getMethod(methodName, argTypes);
// The class we're extending implements this method and
// the JavaScript object doesn't have an override. See
// bug 61226.
continue;
} catch (NoSuchMethodException e) {
// Not implemented by superclass; fall through
}
}
// make sure to generate only one instance of a particular
// method/signature.
String methodSignature = getMethodSignature(method, argTypes);
String methodKey = methodName + methodSignature;
if (! generatedOverrides.has(methodKey)) {
generateMethod(cfw, adapterName, methodName, argTypes,
method.getReturnType(), true);
generatedOverrides.put(methodKey, 0);
generatedMethods.put(methodName, 0);
}
}
}
// Now, go through the superclass's methods, checking for abstract
// methods or additional methods to override.
// generate any additional overrides that the object might contain.
Method[] methods = getOverridableMethods(superClass);
for (int j = 0; j < methods.length; j++) {
Method method = methods[j];
int mods = method.getModifiers();
// if a method is marked abstract, must implement it or the
// resulting class won't be instantiable. otherwise, if the object
// has a property of the same name, then an override is intended.
boolean isAbstractMethod = Modifier.isAbstract(mods);
String methodName = method.getName();
if (isAbstractMethod || functionNames.has(methodName)) {
// make sure to generate only one instance of a particular
// method/signature.
Class[] argTypes = method.getParameterTypes();
String methodSignature = getMethodSignature(method, argTypes);
String methodKey = methodName + methodSignature;
if (! generatedOverrides.has(methodKey)) {
generateMethod(cfw, adapterName, methodName, argTypes,
method.getReturnType(), true);
generatedOverrides.put(methodKey, 0);
generatedMethods.put(methodName, 0);
// if a method was overridden, generate a "super$method"
// which lets the delegate call the superclass' version.
if (!isAbstractMethod) {
generateSuper(cfw, adapterName, superName,
methodName, methodSignature,
argTypes, method.getReturnType());
}
}
}
}
// Generate Java methods for remaining properties that are not
// overrides.
ObjToIntMap.Iterator iter = new ObjToIntMap.Iterator(functionNames);
for (iter.start(); !iter.done(); iter.next()) {
String functionName = (String)iter.getKey();
if (generatedMethods.has(functionName))
continue;
int length = iter.getValue();
Class[] parms = new Class[length];
for (int k=0; k < length; k++)
parms[k] = ScriptRuntime.ObjectClass;
generateMethod(cfw, adapterName, functionName, parms,
ScriptRuntime.ObjectClass, false);
}
return cfw.toByteArray();
}
static Method[] getOverridableMethods(Class clazz)
{
ArrayList list = new ArrayList();
HashSet skip = new HashSet();
// Check superclasses before interfaces so we always choose
// implemented methods over abstract ones, even if a subclass
// re-implements an interface already implemented in a superclass
// (e.g. java.util.ArrayList)
for (Class c = clazz; c != null; c = c.getSuperclass()) {
appendOverridableMethods(c, list, skip);
}
for (Class c = clazz; c != null; c = c.getSuperclass()) {
for (Class intf: c.getInterfaces())
appendOverridableMethods(intf, list, skip);
}
return list.toArray(new Method[list.size()]);
}
private static void appendOverridableMethods(Class c,
ArrayList list, HashSet skip)
{
Method[] methods = c.getDeclaredMethods();
for (int i = 0; i < methods.length; i++) {
String methodKey = methods[i].getName() +
getMethodSignature(methods[i],
methods[i].getParameterTypes());
if (skip.contains(methodKey))
continue; // skip this method
int mods = methods[i].getModifiers();
if (Modifier.isStatic(mods))
continue;
if (Modifier.isFinal(mods)) {
// Make sure we don't add a final method to the list
// of overridable methods.
skip.add(methodKey);
continue;
}
if (Modifier.isPublic(mods) || Modifier.isProtected(mods)) {
list.add(methods[i]);
skip.add(methodKey);
}
}
}
static Class loadAdapterClass(String className, byte[] classBytes)
{
Object staticDomain;
Class domainClass = SecurityController.getStaticSecurityDomainClass();
if(domainClass == CodeSource.class || domainClass == ProtectionDomain.class) {
// use the calling script's security domain if available
ProtectionDomain protectionDomain = SecurityUtilities.getScriptProtectionDomain();
if (protectionDomain == null) {
protectionDomain = JavaAdapter.class.getProtectionDomain();
}
if(domainClass == CodeSource.class) {
staticDomain = protectionDomain == null ? null : protectionDomain.getCodeSource();
}
else {
staticDomain = protectionDomain;
}
}
else {
staticDomain = null;
}
GeneratedClassLoader loader = SecurityController.createLoader(null,
staticDomain);
Class result = loader.defineClass(className, classBytes);
loader.linkClass(result);
return result;
}
public static Function getFunction(Scriptable obj, String functionName)
{
Object x = ScriptableObject.getProperty(obj, functionName);
if (x == Scriptable.NOT_FOUND) {
// This method used to swallow the exception from calling
// an undefined method. People have come to depend on this
// somewhat dubious behavior. It allows people to avoid
// implementing listener methods that they don't care about,
// for instance.
return null;
}
if (!(x instanceof Function))
throw ScriptRuntime.notFunctionError(x, functionName);
return (Function)x;
}
/**
* Utility method which dynamically binds a Context to the current thread,
* if none already exists.
*/
public static Object callMethod(ContextFactory factory,
final Scriptable thisObj,
final Function f, final Object[] args,
final long argsToWrap)
{
if (f == null) {
// See comments in getFunction
return null;
}
if (factory == null) {
factory = ContextFactory.getGlobal();
}
final Scriptable scope = f.getParentScope();
if (argsToWrap == 0) {
return Context.call(factory, f, scope, thisObj, args);
}
Context cx = Context.getCurrentContext();
if (cx != null) {
return doCall(cx, scope, thisObj, f, args, argsToWrap);
} else {
return factory.call(new ContextAction() {
public Object run(Context cx)
{
return doCall(cx, scope, thisObj, f, args, argsToWrap);
}
});
}
}
private static Object doCall(Context cx, Scriptable scope,
Scriptable thisObj, Function f,
Object[] args, long argsToWrap)
{
// Wrap the rest of objects
for (int i = 0; i != args.length; ++i) {
if (0 != (argsToWrap & (1 << i))) {
Object arg = args[i];
if (!(arg instanceof Scriptable)) {
args[i] = cx.getWrapFactory().wrap(cx, scope, arg,
null);
}
}
}
return f.call(cx, scope, thisObj, args);
}
public static Scriptable runScript(final Script script)
{
return (Scriptable)ContextFactory.getGlobal().call(
new ContextAction() {
public Object run(Context cx)
{
ScriptableObject global = ScriptRuntime.getGlobal(cx);
script.exec(cx, global);
return global;
}
});
}
private static void generateCtor(ClassFileWriter cfw, String adapterName,
String superName, Constructor superCtor)
{
short locals = 3; // this + factory + delegee
Class[] parameters = superCtor.getParameterTypes();
// Note that we swapped arguments in app-facing constructors to avoid
// conflicting signatures with serial constructor defined below.
if (parameters.length == 0) {
cfw.startMethod("",
"(Lorg/mozilla/javascript/Scriptable;"
+"Lorg/mozilla/javascript/ContextFactory;)V",
ClassFileWriter.ACC_PUBLIC);
// Invoke base class constructor
cfw.add(ByteCode.ALOAD_0); // this
cfw.addInvoke(ByteCode.INVOKESPECIAL, superName, "", "()V");
} else {
StringBuilder sig = new StringBuilder(
"(Lorg/mozilla/javascript/Scriptable;"
+"Lorg/mozilla/javascript/ContextFactory;");
int marker = sig.length(); // lets us reuse buffer for super signature
for (Class c : parameters) {
appendTypeString(sig, c);
}
sig.append(")V");
cfw.startMethod("", sig.toString(), ClassFileWriter.ACC_PUBLIC);
// Invoke base class constructor
cfw.add(ByteCode.ALOAD_0); // this
short paramOffset = 3;
for (Class parameter : parameters) {
paramOffset += generatePushParam(cfw, paramOffset, parameter);
}
locals = paramOffset;
sig.delete(1, marker);
cfw.addInvoke(ByteCode.INVOKESPECIAL, superName, "", sig.toString());
}
// Save parameter in instance variable "delegee"
cfw.add(ByteCode.ALOAD_0); // this
cfw.add(ByteCode.ALOAD_1); // first arg: Scriptable delegee
cfw.add(ByteCode.PUTFIELD, adapterName, "delegee",
"Lorg/mozilla/javascript/Scriptable;");
// Save parameter in instance variable "factory"
cfw.add(ByteCode.ALOAD_0); // this
cfw.add(ByteCode.ALOAD_2); // second arg: ContextFactory instance
cfw.add(ByteCode.PUTFIELD, adapterName, "factory",
"Lorg/mozilla/javascript/ContextFactory;");
cfw.add(ByteCode.ALOAD_0); // this for the following PUTFIELD for self
// create a wrapper object to be used as "this" in method calls
cfw.add(ByteCode.ALOAD_1); // the Scriptable delegee
cfw.add(ByteCode.ALOAD_0); // this
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/JavaAdapter",
"createAdapterWrapper",
"(Lorg/mozilla/javascript/Scriptable;"
+"Ljava/lang/Object;"
+")Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.PUTFIELD, adapterName, "self",
"Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.RETURN);
cfw.stopMethod(locals);
}
private static void generateSerialCtor(ClassFileWriter cfw,
String adapterName,
String superName)
{
cfw.startMethod("",
"(Lorg/mozilla/javascript/ContextFactory;"
+"Lorg/mozilla/javascript/Scriptable;"
+"Lorg/mozilla/javascript/Scriptable;"
+")V",
ClassFileWriter.ACC_PUBLIC);
// Invoke base class constructor
cfw.add(ByteCode.ALOAD_0); // this
cfw.addInvoke(ByteCode.INVOKESPECIAL, superName, "", "()V");
// Save parameter in instance variable "factory"
cfw.add(ByteCode.ALOAD_0); // this
cfw.add(ByteCode.ALOAD_1); // first arg: ContextFactory instance
cfw.add(ByteCode.PUTFIELD, adapterName, "factory",
"Lorg/mozilla/javascript/ContextFactory;");
// Save parameter in instance variable "delegee"
cfw.add(ByteCode.ALOAD_0); // this
cfw.add(ByteCode.ALOAD_2); // second arg: Scriptable delegee
cfw.add(ByteCode.PUTFIELD, adapterName, "delegee",
"Lorg/mozilla/javascript/Scriptable;");
// save self
cfw.add(ByteCode.ALOAD_0); // this
cfw.add(ByteCode.ALOAD_3); // third arg: Scriptable self
cfw.add(ByteCode.PUTFIELD, adapterName, "self",
"Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.RETURN);
cfw.stopMethod((short)4); // 4: this + factory + delegee + self
}
private static void generateEmptyCtor(ClassFileWriter cfw,
String adapterName,
String superName,
String scriptClassName)
{
cfw.startMethod("", "()V", ClassFileWriter.ACC_PUBLIC);
// Invoke base class constructor
cfw.add(ByteCode.ALOAD_0); // this
cfw.addInvoke(ByteCode.INVOKESPECIAL, superName, "", "()V");
// Set factory to null to use current global when necessary
cfw.add(ByteCode.ALOAD_0);
cfw.add(ByteCode.ACONST_NULL);
cfw.add(ByteCode.PUTFIELD, adapterName, "factory",
"Lorg/mozilla/javascript/ContextFactory;");
// Load script class
cfw.add(ByteCode.NEW, scriptClassName);
cfw.add(ByteCode.DUP);
cfw.addInvoke(ByteCode.INVOKESPECIAL, scriptClassName, "", "()V");
// Run script and save resulting scope
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/JavaAdapter",
"runScript",
"(Lorg/mozilla/javascript/Script;"
+")Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.ASTORE_1);
// Save the Scriptable in instance variable "delegee"
cfw.add(ByteCode.ALOAD_0); // this
cfw.add(ByteCode.ALOAD_1); // the Scriptable
cfw.add(ByteCode.PUTFIELD, adapterName, "delegee",
"Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.ALOAD_0); // this for the following PUTFIELD for self
// create a wrapper object to be used as "this" in method calls
cfw.add(ByteCode.ALOAD_1); // the Scriptable
cfw.add(ByteCode.ALOAD_0); // this
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/JavaAdapter",
"createAdapterWrapper",
"(Lorg/mozilla/javascript/Scriptable;"
+"Ljava/lang/Object;"
+")Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.PUTFIELD, adapterName, "self",
"Lorg/mozilla/javascript/Scriptable;");
cfw.add(ByteCode.RETURN);
cfw.stopMethod((short)2); // this + delegee
}
/**
* Generates code to wrap Java arguments into Object[].
* Non-primitive Java types are left as-is pending conversion
* in the helper method. Leaves the array object on the top of the stack.
*/
static void generatePushWrappedArgs(ClassFileWriter cfw,
Class[] argTypes,
int arrayLength)
{
// push arguments
cfw.addPush(arrayLength);
cfw.add(ByteCode.ANEWARRAY, "java/lang/Object");
int paramOffset = 1;
for (int i = 0; i != argTypes.length; ++i) {
cfw.add(ByteCode.DUP); // duplicate array reference
cfw.addPush(i);
paramOffset += generateWrapArg(cfw, paramOffset, argTypes[i]);
cfw.add(ByteCode.AASTORE);
}
}
/**
* Generates code to wrap Java argument into Object.
* Non-primitive Java types are left unconverted pending conversion
* in the helper method. Leaves the wrapper object on the top of the stack.
*/
private static int generateWrapArg(ClassFileWriter cfw, int paramOffset,
Class argType)
{
int size = 1;
if (!argType.isPrimitive()) {
cfw.add(ByteCode.ALOAD, paramOffset);
} else if (argType == Boolean.TYPE) {
// wrap boolean values with java.lang.Boolean.
cfw.add(ByteCode.NEW, "java/lang/Boolean");
cfw.add(ByteCode.DUP);
cfw.add(ByteCode.ILOAD, paramOffset);
cfw.addInvoke(ByteCode.INVOKESPECIAL, "java/lang/Boolean",
"", "(Z)V");
} else if (argType == Character.TYPE) {
// Create a string of length 1 using the character parameter.
cfw.add(ByteCode.ILOAD, paramOffset);
cfw.addInvoke(ByteCode.INVOKESTATIC, "java/lang/String",
"valueOf", "(C)Ljava/lang/String;");
} else {
// convert all numeric values to java.lang.Double.
cfw.add(ByteCode.NEW, "java/lang/Double");
cfw.add(ByteCode.DUP);
String typeName = argType.getName();
switch (typeName.charAt(0)) {
case 'b':
case 's':
case 'i':
// load an int value, convert to double.
cfw.add(ByteCode.ILOAD, paramOffset);
cfw.add(ByteCode.I2D);
break;
case 'l':
// load a long, convert to double.
cfw.add(ByteCode.LLOAD, paramOffset);
cfw.add(ByteCode.L2D);
size = 2;
break;
case 'f':
// load a float, convert to double.
cfw.add(ByteCode.FLOAD, paramOffset);
cfw.add(ByteCode.F2D);
break;
case 'd':
cfw.add(ByteCode.DLOAD, paramOffset);
size = 2;
break;
}
cfw.addInvoke(ByteCode.INVOKESPECIAL, "java/lang/Double",
"", "(D)V");
}
return size;
}
/**
* Generates code to convert a wrapped value type to a primitive type.
* Handles unwrapping java.lang.Boolean, and java.lang.Number types.
* Generates the appropriate RETURN bytecode.
*/
static void generateReturnResult(ClassFileWriter cfw, Class retType,
boolean callConvertResult)
{
// wrap boolean values with java.lang.Boolean, convert all other
// primitive values to java.lang.Double.
if (retType == Void.TYPE) {
cfw.add(ByteCode.POP);
cfw.add(ByteCode.RETURN);
} else if (retType == Boolean.TYPE) {
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/Context",
"toBoolean", "(Ljava/lang/Object;)Z");
cfw.add(ByteCode.IRETURN);
} else if (retType == Character.TYPE) {
// characters are represented as strings in JavaScript.
// return the first character.
// first convert the value to a string if possible.
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/Context",
"toString",
"(Ljava/lang/Object;)Ljava/lang/String;");
cfw.add(ByteCode.ICONST_0);
cfw.addInvoke(ByteCode.INVOKEVIRTUAL, "java/lang/String",
"charAt", "(I)C");
cfw.add(ByteCode.IRETURN);
} else if (retType.isPrimitive()) {
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/Context",
"toNumber", "(Ljava/lang/Object;)D");
String typeName = retType.getName();
switch (typeName.charAt(0)) {
case 'b':
case 's':
case 'i':
cfw.add(ByteCode.D2I);
cfw.add(ByteCode.IRETURN);
break;
case 'l':
cfw.add(ByteCode.D2L);
cfw.add(ByteCode.LRETURN);
break;
case 'f':
cfw.add(ByteCode.D2F);
cfw.add(ByteCode.FRETURN);
break;
case 'd':
cfw.add(ByteCode.DRETURN);
break;
default:
throw new RuntimeException("Unexpected return type " +
retType.toString());
}
} else {
String retTypeStr = retType.getName();
if (callConvertResult) {
cfw.addLoadConstant(retTypeStr);
cfw.addInvoke(ByteCode.INVOKESTATIC,
"java/lang/Class",
"forName",
"(Ljava/lang/String;)Ljava/lang/Class;");
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/JavaAdapter",
"convertResult",
"(Ljava/lang/Object;"
+"Ljava/lang/Class;"
+")Ljava/lang/Object;");
}
// Now cast to return type
cfw.add(ByteCode.CHECKCAST, retTypeStr);
cfw.add(ByteCode.ARETURN);
}
}
private static void generateMethod(ClassFileWriter cfw, String genName,
String methodName, Class[] parms,
Class returnType, boolean convertResult)
{
StringBuilder sb = new StringBuilder();
int paramsEnd = appendMethodSignature(parms, returnType, sb);
String methodSignature = sb.toString();
cfw.startMethod(methodName, methodSignature,
ClassFileWriter.ACC_PUBLIC);
// Prepare stack to call method
// push factory
cfw.add(ByteCode.ALOAD_0);
cfw.add(ByteCode.GETFIELD, genName, "factory",
"Lorg/mozilla/javascript/ContextFactory;");
// push self
cfw.add(ByteCode.ALOAD_0);
cfw.add(ByteCode.GETFIELD, genName, "self",
"Lorg/mozilla/javascript/Scriptable;");
// push function
cfw.add(ByteCode.ALOAD_0);
cfw.add(ByteCode.GETFIELD, genName, "delegee",
"Lorg/mozilla/javascript/Scriptable;");
cfw.addPush(methodName);
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/JavaAdapter",
"getFunction",
"(Lorg/mozilla/javascript/Scriptable;"
+"Ljava/lang/String;"
+")Lorg/mozilla/javascript/Function;");
// push arguments
generatePushWrappedArgs(cfw, parms, parms.length);
// push bits to indicate which parameters should be wrapped
if (parms.length > 64) {
// If it will be an issue, then passing a static boolean array
// can be an option, but for now using simple bitmask
throw Context.reportRuntimeError0(
"JavaAdapter can not subclass methods with more then"
+" 64 arguments.");
}
long convertionMask = 0;
for (int i = 0; i != parms.length; ++i) {
if (!parms[i].isPrimitive()) {
convertionMask |= (1 << i);
}
}
cfw.addPush(convertionMask);
// go through utility method, which creates a Context to run the
// method in.
cfw.addInvoke(ByteCode.INVOKESTATIC,
"org/mozilla/javascript/JavaAdapter",
"callMethod",
"(Lorg/mozilla/javascript/ContextFactory;"
+"Lorg/mozilla/javascript/Scriptable;"
+"Lorg/mozilla/javascript/Function;"
+"[Ljava/lang/Object;"
+"J"
+")Ljava/lang/Object;");
generateReturnResult(cfw, returnType, convertResult);
cfw.stopMethod((short)paramsEnd);
}
/**
* Generates code to push typed parameters onto the operand stack
* prior to a direct Java method call.
*/
private static int generatePushParam(ClassFileWriter cfw, int paramOffset,
Class paramType)
{
if (!paramType.isPrimitive()) {
cfw.addALoad(paramOffset);
return 1;
}
String typeName = paramType.getName();
switch (typeName.charAt(0)) {
case 'z':
case 'b':
case 'c':
case 's':
case 'i':
// load an int value, convert to double.
cfw.addILoad(paramOffset);
return 1;
case 'l':
// load a long, convert to double.
cfw.addLLoad(paramOffset);
return 2;
case 'f':
// load a float, convert to double.
cfw.addFLoad(paramOffset);
return 1;
case 'd':
cfw.addDLoad(paramOffset);
return 2;
}
throw Kit.codeBug();
}
/**
* Generates code to return a Java type, after calling a Java method
* that returns the same type.
* Generates the appropriate RETURN bytecode.
*/
private static void generatePopResult(ClassFileWriter cfw,
Class retType)
{
if (retType.isPrimitive()) {
String typeName = retType.getName();
switch (typeName.charAt(0)) {
case 'b':
case 'c':
case 's':
case 'i':
case 'z':
cfw.add(ByteCode.IRETURN);
break;
case 'l':
cfw.add(ByteCode.LRETURN);
break;
case 'f':
cfw.add(ByteCode.FRETURN);
break;
case 'd':
cfw.add(ByteCode.DRETURN);
break;
}
} else {
cfw.add(ByteCode.ARETURN);
}
}
/**
* Generates a method called "super$methodName()" which can be called
* from JavaScript that is equivalent to calling "super.methodName()"
* from Java. Eventually, this may be supported directly in JavaScript.
*/
private static void generateSuper(ClassFileWriter cfw,
String genName, String superName,
String methodName, String methodSignature,
Class[] parms, Class returnType)
{
cfw.startMethod("super$" + methodName, methodSignature,
ClassFileWriter.ACC_PUBLIC);
// push "this"
cfw.add(ByteCode.ALOAD, 0);
// push the rest of the parameters.
int paramOffset = 1;
for (Class parm : parms) {
paramOffset += generatePushParam(cfw, paramOffset, parm);
}
// call the superclass implementation of the method.
cfw.addInvoke(ByteCode.INVOKESPECIAL,
superName,
methodName,
methodSignature);
// now, handle the return type appropriately.
Class retType = returnType;
if (!retType.equals(Void.TYPE)) {
generatePopResult(cfw, retType);
} else {
cfw.add(ByteCode.RETURN);
}
cfw.stopMethod((short)(paramOffset + 1));
}
/**
* Returns a fully qualified method name concatenated with its signature.
*/
private static String getMethodSignature(Method method, Class[] argTypes)
{
StringBuilder sb = new StringBuilder();
appendMethodSignature(argTypes, method.getReturnType(), sb);
return sb.toString();
}
static int appendMethodSignature(Class[] argTypes,
Class returnType,
StringBuilder sb)
{
sb.append('(');
int firstLocal = 1 + argTypes.length; // includes this.
for (Class type : argTypes) {
appendTypeString(sb, type);
if (type == Long.TYPE || type == Double.TYPE) {
// adjust for double slot
++firstLocal;
}
}
sb.append(')');
appendTypeString(sb, returnType);
return firstLocal;
}
private static StringBuilder appendTypeString(StringBuilder sb, Class type)
{
while (type.isArray()) {
sb.append('[');
type = type.getComponentType();
}
if (type.isPrimitive()) {
char typeLetter;
if (type == Boolean.TYPE) {
typeLetter = 'Z';
} else if (type == Long.TYPE) {
typeLetter = 'J';
} else {
String typeName = type.getName();
typeLetter = Character.toUpperCase(typeName.charAt(0));
}
sb.append(typeLetter);
} else {
sb.append('L');
sb.append(type.getName().replace('.', '/'));
sb.append(';');
}
return sb;
}
static int[] getArgsToConvert(Class[] argTypes)
{
int count = 0;
for (int i = 0; i != argTypes.length; ++i) {
if (!argTypes[i].isPrimitive())
++count;
}
if (count == 0)
return null;
int[] array = new int[count];
count = 0;
for (int i = 0; i != argTypes.length; ++i) {
if (!argTypes[i].isPrimitive())
array[count++] = i;
}
return array;
}
private static final Object FTAG = "JavaAdapter";
private static final int Id_JavaAdapter = 1;
}
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