/*
* Copyright 2010 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.web.bindery.requestfactory.server;
import com.google.web.bindery.autobean.vm.impl.TypeUtils;
import com.google.web.bindery.requestfactory.shared.BaseProxy;
import com.google.web.bindery.requestfactory.shared.ProxyFor;
import com.google.web.bindery.requestfactory.shared.ProxyForName;
import com.google.web.bindery.requestfactory.shared.RequestContext;
import com.google.web.bindery.requestfactory.shared.RequestFactory;
import com.google.web.bindery.requestfactory.shared.Service;
import com.google.web.bindery.requestfactory.shared.ServiceName;
import com.google.web.bindery.requestfactory.vm.impl.Deobfuscator;
import com.google.web.bindery.requestfactory.vm.impl.OperationKey;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
/**
* Implements all of the resolution methods in ServiceLayer.
*/
final class ResolverServiceLayer extends ServiceLayerDecorator {
private static Deobfuscator deobfuscator;
private static synchronized void updateDeobfuscator(Class<? extends RequestFactory> clazz,
ClassLoader resolveClassesWith) {
Deobfuscator.Builder builder = Deobfuscator.Builder.load(clazz, resolveClassesWith);
if (deobfuscator != null) {
builder.merge(deobfuscator);
}
deobfuscator = builder.build();
}
@Override
public ClassLoader getDomainClassLoader() {
return Thread.currentThread().getContextClassLoader();
}
@Override
public Class<? extends BaseProxy> resolveClass(String typeToken) {
String deobfuscated = deobfuscator.getTypeFromToken(typeToken);
if (deobfuscated == null) {
die(null, "No type for token %s", typeToken);
}
return forName(deobfuscated).asSubclass(BaseProxy.class);
}
@Override
public <T> Class<? extends T> resolveClientType(Class<?> domainClass, Class<T> clientClass,
boolean required) {
if (List.class.isAssignableFrom(domainClass)) {
return List.class.asSubclass(clientClass);
}
if (Set.class.isAssignableFrom(domainClass)) {
return Set.class.asSubclass(clientClass);
}
if (TypeUtils.isValueType(domainClass)) {
return domainClass.asSubclass(clientClass);
}
Class<?> toSearch = domainClass;
while (toSearch != null) {
List<String> clientTypes = deobfuscator.getClientProxies(toSearch.getName());
if (clientTypes != null) {
for (String clientType : clientTypes) {
Class<?> proxy = forName(clientType);
if (clientClass.isAssignableFrom(proxy)) {
return proxy.asSubclass(clientClass);
}
}
}
toSearch = toSearch.getSuperclass();
}
if (required) {
die(null, "The domain type %s cannot be sent to the client", domainClass.getCanonicalName());
}
return null;
}
@Override
public Class<?> resolveDomainClass(Class<?> clazz) {
if (List.class.equals(clazz)) {
return List.class;
} else if (Set.class.equals(clazz)) {
return Set.class;
} else if (BaseProxy.class.isAssignableFrom(clazz)) {
ProxyFor pf = clazz.getAnnotation(ProxyFor.class);
if (pf != null) {
return pf.value();
}
ProxyForName pfn = clazz.getAnnotation(ProxyForName.class);
if (pfn != null) {
Class<?> toReturn = forName(pfn.value());
return toReturn;
}
}
return die(null, "Could not resolve a domain type for client type %s", clazz.getCanonicalName());
}
@Override
public Method resolveDomainMethod(String operation) {
/*
* The validator has already determined the mapping from the RequsetContext
* method to a domain method signature. We'll reuse this calculation instead
* of iterating over all methods.
*/
String domainDescriptor = deobfuscator.getDomainMethodDescriptor(operation);
if (domainDescriptor == null) {
return die(null, "No domain method descriptor is mapped to operation %s", operation);
}
Class<?>[] domainArgs = getArgumentTypes(domainDescriptor);
Class<? extends RequestContext> requestContext = getTop().resolveRequestContext(operation);
Class<?> serviceImplementation = getTop().resolveServiceClass(requestContext);
// Request<FooProxy> someMethod(int a, double b, FooProxy c);
Method requestContextMethod = getTop().resolveRequestContextMethod(operation);
Throwable ex;
try {
return serviceImplementation.getMethod(requestContextMethod.getName(), domainArgs);
} catch (SecurityException e) {
ex = e;
} catch (NoSuchMethodException e) {
ex = e;
}
return die(ex,
"Could not find method in implementation %s matching descriptor %s for operation %s",
serviceImplementation.getCanonicalName(), domainDescriptor, operation);
}
@Override
public Class<? extends RequestContext> resolveRequestContext(String operation) {
String requestContextClass = deobfuscator.getRequestContext(operation);
if (requestContextClass == null) {
die(null, "No RequestContext for operation %s", operation);
}
return forName(requestContextClass).asSubclass(RequestContext.class);
}
@Override
public Method resolveRequestContextMethod(String operation) {
Class<?> searchIn = getTop().resolveRequestContext(operation);
String methodName = deobfuscator.getRequestContextMethodName(operation);
String descriptor = deobfuscator.getRequestContextMethodDescriptor(operation);
Class<?>[] params = getArgumentTypes(descriptor);
try {
return searchIn.getMethod(methodName, params);
} catch (NoSuchMethodException ex) {
return report("Could not locate %s operation %s", RequestContext.class.getSimpleName(),
operation);
}
}
@Override
public Class<? extends RequestFactory> resolveRequestFactory(String binaryName) {
Class<? extends RequestFactory> toReturn = forName(binaryName).asSubclass(RequestFactory.class);
updateDeobfuscator(toReturn, getTop().getDomainClassLoader());
return toReturn;
}
@Override
public Class<?> resolveServiceClass(Class<? extends RequestContext> requestContextClass) {
Class<?> searchIn = null;
Service s = requestContextClass.getAnnotation(Service.class);
if (s != null) {
searchIn = s.value();
}
ServiceName sn = requestContextClass.getAnnotation(ServiceName.class);
if (sn != null) {
searchIn = forName(sn.value());
}
if (searchIn == null) {
die(null, "The %s type %s did not specify a service type", RequestContext.class
.getSimpleName(), requestContextClass.getCanonicalName());
}
return searchIn;
}
@Override
public String resolveTypeToken(Class<? extends BaseProxy> clazz) {
return OperationKey.hash(clazz.getName());
}
/**
* Call {@link Class#forName(String)} and report any errors through
* {@link #die()}.
*/
private Class<?> forName(String name) {
try {
return Class.forName(name, false, getTop().getDomainClassLoader());
} catch (ClassNotFoundException e) {
return die(e, "Could not locate class %s", name);
}
}
private Class<?>[] getArgumentTypes(String descriptor) {
assert descriptor.charAt(0) == '(';
ArrayList<Class<?>> params = new ArrayList<Class<?>>();
loop:
for (int i = 1; i < descriptor.length(); i++) {
switch (descriptor.charAt(i)) {
case 'Z':
params.add(boolean.class);
break;
case 'B':
params.add(byte.class);
break;
case 'C':
params.add(char.class);
break;
case 'D':
params.add(double.class);
break;
case 'F':
params.add(float.class);
break;
case 'I':
params.add(int.class);
break;
case 'J':
params.add(long.class);
break;
case 'S':
params.add(short.class);
break;
case 'V':
params.add(void.class);
break;
case 'L':
int end = descriptor.indexOf(';', i);
params.add(forName(descriptor.substring(i + 1, end).replace('/', '.')));
i = end;
break;
case '[':
return die(null, "Unsupported Type (array) used in operation descriptor: %s", descriptor);
case ')':
break loop;
default:
// Error in this switch statement
return die(null, "Invalid operation descriptor: %s", descriptor);
}
}
return params.toArray(new Class<?>[params.size()]);
}
}