package com.googlecode.gwt.test.internal.resources;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javassist.CtClass;
import javassist.NotFoundException;
import com.google.gwt.resources.client.ClientBundle;
import com.google.gwt.resources.client.ClientBundle.Source;
import com.google.gwt.resources.ext.DefaultExtensions;
import com.googlecode.gwt.test.exceptions.GwtTestResourcesException;
import com.googlecode.gwt.test.internal.GwtClassPool;
class ClientBundleProxyFactory {
private static class ClientBundleMethodsRegistry {
private final CtClass ctClass;
private final Map<Method, List<URL>> resourceURLMap = new HashMap<Method, List<URL>>();
public ClientBundleMethodsRegistry(Class<? extends ClientBundle> clazz) {
ctClass = GwtClassPool.getCtClass(clazz);
}
public List<URL> getResourceURL(Method method) throws Exception {
List<URL> resourceURLs = resourceURLMap.get(method);
if (resourceURLs == null) {
resourceURLs = computeResourceURLs(method);
resourceURLMap.put(method, resourceURLs);
}
return resourceURLs;
}
private List<URL> computeResourceURLs(Method method) throws NotFoundException,
URISyntaxException {
List<ResourceFileEntry> filesSimpleNames = new ArrayList<ResourceFileEntry>();
boolean computeExtensions = false;
Source source = method.getAnnotation(Source.class);
if (source != null) {
for (String value : source.value()) {
filesSimpleNames.add(new ResourceFileEntry(value, method));
}
}
if (filesSimpleNames.isEmpty()) {
// no @Source annotation detected
filesSimpleNames.add(new ResourceFileEntry(method.getName(), method));
computeExtensions = true;
}
List<URL> existingFiles = new ArrayList<URL>();
for (ResourceFileEntry resourceEntry : filesSimpleNames) {
String resourceName = resourceEntry.resourceName;
Class<?> declaringClass = resourceEntry.resourceMethod.getDeclaringClass();
String baseDir = declaringClass.getPackage().getName().replaceAll("\\.", "/") + "/";
String resourceNameWithPackage = resourceName.startsWith(baseDir) ? resourceName
: baseDir + resourceName;
if (computeExtensions) {
String[] extensions = getResourceDefaultExtensions(method);
for (String extension : extensions) {
// try to find the file directly in the classpath
String possibleFile = resourceName + extension;
URL url = this.getClass().getClassLoader().getResource(possibleFile);
if (url != null) {
existingFiles.add(url);
} else {
// try to find the file relative to the ClientBundle
// subinterface's package
String possibleFileWithPackage = resourceNameWithPackage + extension;
URL urlWithPackage = this.getClass().getClassLoader().getResource(
possibleFileWithPackage);
if (urlWithPackage != null) {
existingFiles.add(urlWithPackage);
}
}
}
} else {
URL url = this.getClass().getClassLoader().getResource(resourceName);
if (url != null) {
existingFiles.add(url);
} else {
// try to find the file relative to the ClientBundle
// subinterface's package
URL urlWithPackage = this.getClass().getClassLoader().getResource(
resourceNameWithPackage);
if (urlWithPackage != null) {
existingFiles.add(urlWithPackage);
}
}
}
}
if (existingFiles.isEmpty()) {
throw new GwtTestResourcesException("No resource file found for method '"
+ ctClass.getName() + "." + method.getName() + "()'");
}
return existingFiles;
}
private String[] getResourceDefaultExtensions(Method method) {
DefaultExtensions annotation = method.getReturnType().getAnnotation(
DefaultExtensions.class);
if (annotation == null) {
throw new GwtTestResourcesException(
method.getReturnType().getSimpleName()
+ " does not define a default extension for resource file. You should use a correct @"
+ Source.class.getSimpleName() + " annotation on "
+ method.getDeclaringClass().getSimpleName() + "." + method.getName()
+ "() method");
} else {
return annotation.value();
}
}
}
private static class ResourceFileEntry {
private final Method resourceMethod;
private final String resourceName;
public ResourceFileEntry(String resourceName, Method resourceMethod) {
this.resourceName = resourceName;
this.resourceMethod = resourceMethod;
}
}
private static Map<String, ClientBundleProxyFactory> factoryMap = new HashMap<String, ClientBundleProxyFactory>();
public static <T extends ClientBundle> ClientBundleProxyFactory getFactory(Class<T> clazz) {
ClientBundleProxyFactory factory = factoryMap.get(clazz.getName());
if (factory == null) {
factory = new ClientBundleProxyFactory(clazz);
factoryMap.put(clazz.getName(), factory);
}
return factory;
}
private final ClientBundleMethodsRegistry methodRegistry;
private final Class<? extends ClientBundle> proxiedClass;
private ClientBundleProxyFactory(Class<? extends ClientBundle> proxiedClass) {
this.proxiedClass = proxiedClass;
methodRegistry = new ClientBundleMethodsRegistry(proxiedClass);
}
@SuppressWarnings("unchecked")
public <T extends ClientBundle> T createProxy() {
InvocationHandler ih = new InvocationHandler() {
private final Map<Method, Object> cache = new HashMap<Method, Object>();
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
Object result = cache.get(method);
if (result == null) {
// create a ResourcePrototypeProxyBuilder with the good args
Class<?> resourcePrototypeClass = method.getReturnType();
String name = method.getName();
List<URL> resourceURL = methodRegistry.getResourceURL(method);
ResourcePrototypeProxyBuilder builder = ResourcePrototypeProxyBuilder.createBuilder(
resourcePrototypeClass, proxiedClass).name(name).resourceURLs(resourceURL);
result = builder.build();
cache.put(method, result);
}
return result;
}
};
return (T) Proxy.newProxyInstance(proxiedClass.getClassLoader(),
new Class<?>[]{proxiedClass}, ih);
}
}