/*
* Copyright 2006-2008 Web Cohesion
*
* 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 org.codehaus.enunciate.modules.gwt;
import com.google.gwt.user.server.rpc.RemoteServiceServlet;
import org.codehaus.enunciate.service.DefaultSecurityExceptionChecker;
import org.codehaus.enunciate.service.SecurityExceptionChecker;
import org.codehaus.enunciate.webapp.ComponentPostProcessor;
import javax.jws.WebMethod;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.util.HashMap;
/**
* Base implementation for a GWT endpoint.
*
* @author Ryan Heaton
*/
public abstract class GWTEndpointImpl extends RemoteServiceServlet {
private final HashMap<String, Method> operationNames2Methods = new HashMap<String, Method>();
protected Object serviceBean;
private SecurityExceptionChecker securityChecker = new DefaultSecurityExceptionChecker();
protected GWTEndpointImpl(Object serviceBean) {
this.serviceBean = serviceBean;
for (Method method : getServiceInterface().getMethods()) {
String operationName = method.getName();
WebMethod webMethodInfo = method.getAnnotation(WebMethod.class);
if ((webMethodInfo != null) && (!"".equals(webMethodInfo.operationName()))) {
operationName = webMethodInfo.operationName();
}
this.operationNames2Methods.put(operationName, method);
}
}
@Override
public void init(ServletConfig servletConfig) throws ServletException {
super.init(servletConfig);
ServletContext servletContext = servletConfig.getServletContext();
ComponentPostProcessor postProcessor = (ComponentPostProcessor) servletContext.getAttribute(ComponentPostProcessor.class.getName());
if (postProcessor != null) {
postProcessor.postProcess(this);
}
}
protected final Object invokeOperation(String operationName, Object... params) throws Exception {
Method method = this.operationNames2Methods.get(operationName);
if (method == null) {
throw new NoSuchMethodError("No such method: " + operationName);
}
GWTMappingContext mappingContext = new GWTMappingContext();
Type[] paramTypes = method.getGenericParameterTypes();
if (paramTypes.length != params.length) {
throw new IllegalArgumentException(String.format("Wrong number of parameters for operation '%s'. Expected %s, got %s.", operationName, paramTypes.length, params.length));
}
Object[] mappedParams = new Object[paramTypes.length];
for (int i = 0; i < paramTypes.length; i++) {
GWTMapper paramMapper = GWTMapperIntrospector.getGWTMapperForGWTObject(params[i]);
if (paramMapper == null) {
paramMapper = GWTMapperIntrospector.getGWTMapper(paramTypes[i]);
}
mappedParams[i] = paramMapper.toJAXB(params[i], mappingContext);
}
Object returnValue;
try {
returnValue = method.invoke(serviceBean, mappedParams);
}
catch (InvocationTargetException e) {
Throwable targetException = e.getTargetException();
for (int i = 0; i < method.getExceptionTypes().length; i++) {
Class exceptionType = method.getExceptionTypes()[i];
if (exceptionType.isInstance(targetException)) {
throw (Exception) GWTMapperIntrospector.getGWTMapper(targetException.getClass(), exceptionType, null, null).toGWT(targetException, mappingContext);
}
}
if (targetException instanceof Error) {
throw (Error) targetException;
}
else {
throw (Exception) targetException;
}
}
if (method.getReturnType() != Void.TYPE) {
returnValue = returnValue != null ? GWTMapperIntrospector.getGWTMapper(returnValue.getClass(), method.getGenericReturnType(), null, null).toGWT(returnValue, mappingContext) : null;
}
return returnValue;
}
@Override
protected void doUnexpectedFailure(Throwable throwable) {
if (securityChecker.isAuthenticationFailed(throwable)) {
writeErrorResponse(HttpServletResponse.SC_UNAUTHORIZED, throwable);
} else if (securityChecker.isAccessDenied(throwable)) {
writeErrorResponse(HttpServletResponse.SC_FORBIDDEN, throwable);
} else {
super.doUnexpectedFailure(throwable);
}
}
private void writeErrorResponse(int statusCode, Throwable throwable) {
HttpServletResponse response = getThreadLocalResponse();
response.setContentType("text/plain");
response.setStatus(statusCode);
try {
response.getOutputStream().write(String.valueOf(throwable.getMessage()).getBytes("UTF-8"));
} catch (IOException e) {
getServletContext().log("Failed to write error message", e);
}
}
/**
* Set the security exception checker.
*
* @param securityChecker The security exception checker.
*/
public void setSecurityChecker(SecurityExceptionChecker securityChecker) {
this.securityChecker = securityChecker;
}
/**
* The service interface.
*
* @return The service interface.
*/
protected abstract Class getServiceInterface();
}