com.gwtplatform.dispatch.client.gin.AbstractDispatchAsyncModule Maven / Gradle / Ivy
/**
* Copyright 2011 ArcBees 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.gwtplatform.dispatch.client.gin;
import com.google.gwt.inject.client.AbstractGinModule;
import com.gwtplatform.dispatch.client.DefaultExceptionHandler;
import com.gwtplatform.dispatch.client.DefaultSecurityCookieAccessor;
import com.gwtplatform.dispatch.client.ExceptionHandler;
import com.gwtplatform.dispatch.client.actionhandler.ClientActionHandlerRegistry;
import com.gwtplatform.dispatch.client.actionhandler.DefaultClientActionHandlerRegistry;
import com.gwtplatform.dispatch.shared.SecurityCookieAccessor;
/**
* This gin module provides provides access to the {@link DispatchAsync}
* singleton, which is used to make remote procedure calls to the server. This
* module requires an {@link ExceptionHandler} and a
* {@link SecurityCookieAccessor}. By default, these will be bound to
* {@link DefaultExceptionHandler} and {@link DefaultSecurityCookieAccessor}
* respectively.
*
* If you want to prevent XSRF attack (you use secured
* {@link com.gwtplatform.dispatch.shared.Action}s) the default
* {@link EmptySecurityCookieAccessor} could leave your application vulnerable
* to XSRF attacks. For more details see this document. For more security use {@link DispatchAsyncSecureModule}.
*
* If you don't need XSRF protection, you can use directly this module with your
* {@link com.google.gwt.inject.client.Ginjector}, i.e.:
*
*
* {@literal @}GinModules( { {@link AbstractDispatchAsyncModule}.class, ... }
*
* For customization, skip the previous step and install the module in one of
* your {@link #configure()} methods:
*
*
* install(new DispatchAsyncModule.Builder().exceptionHandler(
* MyExceptionHandler.class).sessionAccessor(
* MySecurityCookieAccessor.class).build());
*
* You can pass {@code null} as any of the two parameter to fallback to the
* default.
*
* @author David Peterson
* @author Philippe Beaudoin
* @author Brendan Doherty
*/
public abstract class AbstractDispatchAsyncModule extends AbstractGinModule {
private static Boolean alreadyBound = false;
private static Class boundType;
protected final Class exceptionHandlerType;
protected final Class sessionAccessorType;
protected final Class clientActionHandlerRegistryType;
/**
* /**
* A {@link AbstractDispatchAsyncModule} builder.
*
* By default, this builder configures the {@link AbstractDispatchAsyncModule} to use
* {@link DefaultExceptionHandler}, {@link DefaultSecurityCookieAccessor}, and
* {@link DefaultClientActionHandlerRegistry}.
*
* @author Brendan Doherty
*/
public abstract static class Builder {
protected Class exceptionHandlerType = DefaultExceptionHandler.class;
protected Class sessionAccessorType = DefaultSecurityCookieAccessor.class;
protected Class clientActionHandlerRegistryType =
DefaultClientActionHandlerRegistry.class;
/**
* Constructs {@link AbstractDispatchAsyncModule} builder.
*/
public Builder() {
}
/**
* Specify an alternative exception handler.
*
* @param exceptionHandlerType The {@link ExceptionHandler} class.
* @return a {@link Builder} object.
*/
public Builder exceptionHandler(Class exceptionHandlerType) {
this.exceptionHandlerType = exceptionHandlerType;
return this;
}
/**
* Specify an alternate session accessor.
*
* @param sessionAccessorType The {@link SecurityCookieAccessor} class.
* @return a {@link Builder} object.
*/
public Builder sessionAccessor(Class sessionAccessorType) {
this.sessionAccessorType = sessionAccessorType;
return this;
}
/**
* Specify an alternate client action handler registry.
*
* @param clientActionHandlerRegistryType
* A {@link ClientActionHandlerRegistry} class.
* @return a {@link Builder} object.
*/
public Builder clientActionHandlerRegistry(
Class clientActionHandlerRegistryType) {
this.clientActionHandlerRegistryType = clientActionHandlerRegistryType;
return this;
}
/**
* Build the {@link AbstractDispatchAsyncModule}.
*
* @return The built {@link AbstractDispatchAsyncModule}.
*/
public abstract AbstractDispatchAsyncModule build();
}
protected AbstractDispatchAsyncModule(Builder builder) {
this.exceptionHandlerType = builder.exceptionHandlerType;
this.sessionAccessorType = builder.sessionAccessorType;
this.clientActionHandlerRegistryType = builder.clientActionHandlerRegistryType;
}
@Override
protected void configure() {
if (alreadyBound) {
if (!boundType.equals(getClass())) {
throw new RuntimeException("You are trying to use more than one DispatchAsync implementation. " +
boundType.getName() + " was already installed.");
}
} else {
alreadyBound = true;
boundType = getClass();
bind(ExceptionHandler.class).to(exceptionHandlerType);
bind(SecurityCookieAccessor.class).to(sessionAccessorType);
bind(ClientActionHandlerRegistry.class).to(clientActionHandlerRegistryType).asEagerSingleton();
}
}
}