Handle getLambdaAccessMethod(Handle implMethod) {
if (!implMethod.getOwner().equals(className)) {
return implMethod;
}
if (Flags.hasFlag(classAccess, ACC_INTERFACE)) {
// the method will be relocated to a companion class
return implMethod;
}
// TODO: do not generate an access method if the impl method is not private (probably not
// implementable with a single pass)
String name = "access$lambda$" + lambdaAccessToImplMethods.size();
String desc = getLambdaAccessMethodDesc(implMethod);
Handle accessMethod = new Handle(H_INVOKESTATIC, className, name, desc);
lambdaAccessToImplMethods.put(accessMethod, implMethod);
return accessMethod;
}
@Override
public void visitEnd() {
for (Map.Entry<Handle, Handle> entry : lambdaAccessToImplMethods.entrySet()) {
Handle accessMethod = entry.getKey();
Handle implMethod = entry.getValue();
Bytecode.generateDelegateMethod(cv, ACC_STATIC | ACC_SYNTHETIC, accessMethod, implMethod);
}
super.visitEnd();
}
/**
* Visit every class/interface this proxy should implement, and generate the appropriate bytecode
* for delegation if available.
*
* @param clazz an class for which to generate bytecode
*/
private void visitClass(final Class clazz) {
Method[] methods = clazz.getDeclaredMethods();
for (Method method : methods) {
Class<?>[] exceptionTypes = method.getExceptionTypes();
String[] exceptions = new String[exceptionTypes.length];
for (int i = 0; i < exceptions.length; i++) {
exceptions[i] = BytecodeHelper.getClassInternalName(exceptionTypes[i]);
}
// for each method defined in the class, generate the appropriate delegation bytecode
visitMethod(
method.getModifiers(),
method.getName(),
BytecodeHelper.getMethodDescriptor(method.getReturnType(), method.getParameterTypes()),
null,
exceptions);
}
Constructor[] constructors = clazz.getDeclaredConstructors();
for (Constructor method : constructors) {
Class<?>[] exceptionTypes = method.getExceptionTypes();
String[] exceptions = new String[exceptionTypes.length];
for (int i = 0; i < exceptions.length; i++) {
exceptions[i] = BytecodeHelper.getClassInternalName(exceptionTypes[i]);
}
// for each method defined in the class, generate the appropriate delegation bytecode
visitMethod(
method.getModifiers(),
"<init>",
BytecodeHelper.getMethodDescriptor(Void.TYPE, method.getParameterTypes()),
null,
exceptions);
}
for (Class intf : clazz.getInterfaces()) {
visitClass(intf);
}
Class superclass = clazz.getSuperclass();
if (superclass != null) visitClass(superclass);
// Ultimately, methods can be available in the closure map which are not defined by the
// superclass
// nor the interfaces
for (Map.Entry<String, Boolean> entry : delegatedClosures.entrySet()) {
Boolean visited = entry.getValue();
if (!visited) {
String name = entry.getKey();
if (!"*".equals(name)) {
// generate a new method
visitMethod(ACC_PUBLIC, name, "([Ljava/lang/Object;)Ljava/lang/Object;", null, null);
}
}
}
}
@Override
public MethodVisitor visitMethod(
final int access,
final String name,
final String desc,
final String signature,
final String[] exceptions) {
Object key = Arrays.asList(name, desc);
if (visitedMethods.contains(key)) return EMPTY_VISITOR;
if (Modifier.isPrivate(access)
|| Modifier.isNative(access)
|| ((access & ACC_SYNTHETIC) != 0)) {
// do not generate bytecode for private methods
return EMPTY_VISITOR;
}
int accessFlags = access;
visitedMethods.add(key);
if ((objectDelegateMethods.contains(name)
|| delegatedClosures.containsKey(name)
|| (!"<init>".equals(name) && hasWildcard))
&& !Modifier.isStatic(access)
&& !Modifier.isFinal(access)) {
if (!GROOVYOBJECT_METHOD_NAMESS.contains(name)) {
if (Modifier.isAbstract(access)) {
// prevents the proxy from being abstract
accessFlags -= ACC_ABSTRACT;
}
if (delegatedClosures.containsKey(name) || (!"<init>".equals(name) && hasWildcard)) {
delegatedClosures.put(name, Boolean.TRUE);
return makeDelegateToClosureCall(name, desc, signature, exceptions, accessFlags);
}
if (generateDelegateField && objectDelegateMethods.contains(name)) {
return makeDelegateCall(name, desc, signature, exceptions, accessFlags);
}
delegatedClosures.put(name, Boolean.TRUE);
return makeDelegateToClosureCall(name, desc, signature, exceptions, accessFlags);
}
} else if ("<init>".equals(name)
&& (Modifier.isPublic(access) || Modifier.isProtected(access))) {
return createConstructor(access, name, desc, signature, exceptions);
} else if (Modifier.isAbstract(access) && !GROOVYOBJECT_METHOD_NAMESS.contains(name)) {
accessFlags -= ACC_ABSTRACT;
MethodVisitor mv = super.visitMethod(accessFlags, name, desc, signature, exceptions);
mv.visitCode();
Type[] args = Type.getArgumentTypes(desc);
if (emptyBody) {
Type returnType = Type.getReturnType(desc);
if (returnType == Type.VOID_TYPE) {
mv.visitInsn(RETURN);
} else {
int loadIns = getLoadInsn(returnType);
switch (loadIns) {
case ILOAD:
mv.visitInsn(ICONST_0);
break;
case LLOAD:
mv.visitInsn(LCONST_0);
break;
case FLOAD:
mv.visitInsn(FCONST_0);
break;
case DLOAD:
mv.visitInsn(DCONST_0);
break;
default:
mv.visitInsn(ACONST_NULL);
}
mv.visitInsn(getReturnInsn(returnType));
mv.visitMaxs(2, registerLen(args) + 1);
}
} else {
// for compatibility with the legacy proxy generator, we should throw an
// UnsupportedOperationException
// instead of an AbtractMethodException
mv.visitTypeInsn(NEW, "java/lang/UnsupportedOperationException");
mv.visitInsn(DUP);
mv.visitMethodInsn(
INVOKESPECIAL, "java/lang/UnsupportedOperationException", "<init>", "()V");
mv.visitInsn(ATHROW);
mv.visitMaxs(2, registerLen(args) + 1);
}
mv.visitEnd();
}
return EMPTY_VISITOR;
}
/**
* Construct a proxy generator. This generator is used when we need to create a proxy object for a
* class or an interface given a map of closures.
*
* @param closureMap the delegates implementations
* @param superClass corresponding to the superclass class visitor
* @param interfaces extra interfaces the proxy should implement
* @param proxyLoader the class loader which should be used to load the generated proxy
* @param delegateClass if not null, generate a delegate field with the corresponding class
* @param emptyBody if set to true, the unimplemented abstract methods will receive an empty body
* instead of throwing an {@link UnsupportedOperationException}.
*/
public ProxyGeneratorAdapter(
final Map<Object, Object> closureMap,
final Class superClass,
final Class[] interfaces,
final ClassLoader proxyLoader,
final boolean emptyBody,
final Class delegateClass) {
super(new ClassWriter(0));
this.visitedMethods = new LinkedHashSet<Object>();
this.delegatedClosures =
closureMap.isEmpty() ? EMPTY_DELEGATECLOSURE_MAP : new HashMap<String, Boolean>();
boolean wildcard = false;
for (Map.Entry<Object, Object> entry : closureMap.entrySet()) {
String name = entry.getKey().toString();
if ("*".equals(name)) {
wildcard = true;
}
this.delegatedClosures.put(name, Boolean.FALSE);
}
this.hasWildcard = wildcard;
// if we have to delegate to another object, generate the appropriate delegate field
// and collect the name of the methods for which delegation is active
this.generateDelegateField = delegateClass != null;
this.objectDelegateMethods =
generateDelegateField
? createDelegateMethodList(delegateClass, interfaces)
: EMPTY_STRING_SET;
this.delegateClass = delegateClass;
// a proxy is supposed to be a concrete class, so it cannot extend an interface.
// If the provided superclass is an interface, then we replace the superclass with Object
// and add this interface to the list of implemented interfaces
boolean isSuperClassAnInterface = superClass.isInterface();
this.superClass = isSuperClassAnInterface ? Object.class : superClass;
// create the base list of classes which have possible methods to be overloaded
this.classList = new LinkedList<Class>();
this.classList.add(superClass);
if (generateDelegateField) {
classList.add(delegateClass);
}
if (interfaces != null) {
Collections.addAll(this.classList, interfaces);
}
this.proxyName = proxyName();
this.loader = proxyLoader != null ? new InnerLoader(proxyLoader) : findClassLoader(superClass);
this.emptyBody = emptyBody;
// generate bytecode
ClassWriter writer = (ClassWriter) cv;
ClassReader cr = createClassVisitor(Object.class);
cr.accept(this, 0);
byte[] b = writer.toByteArray();
// CheckClassAdapter.verify(new ClassReader(b), true, new PrintWriter(System.err));
cachedClass = loader.defineClass(proxyName.replace('/', '.'), b);
// cache no-arg constructor
Class[] args =
generateDelegateField ? new Class[] {Map.class, delegateClass} : new Class[] {Map.class};
Constructor constructor;
try {
constructor = cachedClass.getConstructor(args);
} catch (NoSuchMethodException e) {
constructor = null;
}
cachedNoArgConstructor = constructor;
}