org.directwebremoting.guice.package-info Maven / Gradle / Ivy
Show all versions of dwr Show documentation
/**
*
* This package provides support for
* Guice
* dependency injection in DWR-based web applications.
* This documentation assumes you already understand Guice concepts.
*
*
* To use this support minimally,
*
* - install a concrete extension of
* {@link org.directwebremoting.guice.DwrGuiceServletContextListener}
* as a {@code
} in your web application's configuration
* file ({@code web.xml}),
* - install {@link org.directwebremoting.guice.DwrGuiceServlet} for all
* requests to {@code /dwr/*}.
*
* For example:
*
*
* <listener>
* <listener-class>org.myorg.myproj.MyServletContextListener</listener-class>
* </listener>
*
* <servlet>
* <servlet-name>dwr-invoker</servlet-name>
* <servlet-class>org.directwebremoting.guice.DwrGuiceServlet</servlet-class>
* </servlet>
*
* <servlet-mapping>
* <servlet-name>dwr-invoker</servlet-name>
* <url-pattern>/dwr/*</url-pattern>
* </servlet-mapping>
*
*
* {@link org.directwebremoting.guice.DwrGuiceServletContextListener DwrGuiceServletContextListener}
* is also an abstract Guice module; it extends
* {@link org.directwebremoting.guice.AbstractDwrModule AbstractDwrModule},
* which in turn extends Guice's {@link com.google.inject.AbstractModule}.
* Your listener class must define
* {@link org.directwebremoting.guice.AbstractDwrModule#configure configure};
* this is where you do your Guice binding.
* You can also put binding code in a separate class or classes with
* {@link com.google.inject.AbstractModule#install AbstractModule.install}.
*
*
* Use {@link org.directwebremoting.guice.GuiceCreator GuiceCreator}
* when annotating classes with {@code RemoteProxy}. When you use a
* {@code GuiceCreator} to create your remoted objects, it gets an
* instance from a Guice injector using your bindings.
*
*
* For bind-time control over how JavaScript names map to Java targets, use the
* {@link org.directwebremoting.guice.AbstractDwrModule#bindRemoted(Class) bindRemoted}
* or
* {@link org.directwebremoting.guice.AbstractDwrModule#bindRemotedAs(String,Class) bindRemotedAs}
* methods. The target of the script can be an abstract class or interface
* bound in the normal Guice way to a concrete class, instance, or provider.
* In that case only the methods defined on the abstract class or
* interface are accessible, even if the implementing class has other public
* methods. You can supply different bindings for different script names, including
* using the same interface with different implementations for different script names,
* or different interfaces for different script names mapping to the same implementation
* type (assuming it implements both interfaces).
*
*
* You can bind a type or type pattern string to a custom converter with
* {@link org.directwebremoting.guice.AbstractDwrModule#bindConversion(Class) bindConversion},
* and you can put Ajax filters on scripts with
* {@link org.directwebremoting.guice.AbstractDwrModule#bindFilter(String) bindFilter}.
* Note, however, that you can achieve the same effect (and more flexibly) using Guice's
* {@code bindInterceptors} method.
*
*
* You can install your own DWR configurator using
* {@code bind(Configurator.class).toInstance(yourConfigurator)},
* which then overrides any {@code dwr.xml} configuration.
* You'll probably want to use a
* {@link org.directwebremoting.fluent.FluentConfigurator FluentConfigurator}
* for this purpose.
*
*
* You can still configure DWR's settings normally via {@code }
* directives in {@code web.xml}, but usually there is no need to. Most DWR
* settings can be set with
* {@link org.directwebremoting.guice.AbstractDwrModule#bindParameter(ParamName) bindParameter}.
* The {@link org.directwebremoting.guice.ParamName ParamName}
* enum type lists the available parameters.
*
*
* To be able to use the DWR scopes for all your injected objects, not just
* DWR-remoted objects, your binding code should call
* {@link org.directwebremoting.guice.AbstractDwrModule#bindDwrScopes() bindDwrScopes}
* at some point.
*
*
* For creating your own scopes where the instance injected depends on some
* run-time value, create a concrete extension of
* {@link org.directwebremoting.guice.AbstractContextScope AbstractContextScope}.
*
*
* This example illustrates two ways to define remoted objects,
* calling {@code bindRemotedAs} and annotating with {@code @RemoteProxy};
* two ways to define conversions, using {@code bindConversion}
* and using a custom configurator; how to register annotated classes
* at bind-time; how to bind a script name to an {@code AjaxFilter}; and
* how to set a DWR parameter (debug, in this case) at bind-time.
* It does not use an {@code } directive, and it doesn't have
* a {@code dwr.xml}.
*
*
* public final class MyServletContextListener extends DwrGuiceServletContextListener
* {
* protected void configure()
* {
* bindRemotedAs("Hello", HelloService.class)
* .to(HelloServiceImpl.class)
* .in(DwrScopes.APPLICATION);
*
* bindFilter("Hello")
* .to(TraceFilter.class);
*
* bind(MessageService.class)
* .to(MessageServiceImpl.class)
* .in(DwrScopes.SCRIPT);
*
* bindAnnotatedClasses(
* DomainService.class, // @RemoteProxy(creator=GuiceCreator.class)/@RemoteMethod
* HelloRecordImpl.class // @DataTransferObject/@RemoteProperty
* );
*
* // When converting HelloRecord, use existing converter for HelloRecordImpl.
* bindConversion(HelloRecord.class, HelloRecordImpl.class);
*
* bindConversion(DateTime.class)
* .toInstance(DateTimeConverter.get("yyyy-MM-dd hh:mm a"));
*
* bind(Configurator.class).toInstance(new FluentConfigurator()
* {
* public void configure() {
* String localTime = "localTime";
* withConverterType(localTime, DateTimeConverter.class.getName());
* withConverter(localTime, LocalTime.class.getName())
* .addParam("format", "yyyy-MM-dd");
* }
* });
*
* bindParameter(DEBUG).to(true);
*
* bindDwrScopes();
* }
* }
*
*
* Note that because application scope is larger than script session scope,
* {@code HelloServiceImpl} has an injected constructor (not shown here)
* that takes a {@code Provider} rather than a plain
* {@code MessageService}.
*
*
* There are four classes with names that start with "Internal". These classes
* have to be public with a parameterless constructor so the non-Guicy DWR
* machinery can create them. They are not meant to be used directly.
*
*
* The classes that handle DWR scopes are modeled on the classes in the
* {@code com.google.inject.servlet} package, but are independent of them.
* You do not need to install the Guice {@code ServletModule} and
* {@code GuiceFilter} to use the DWR scopes, but if you do, you have to be
* careful to install the DWR scopes without creating conflicting bindings
* for request, response, and session. Calling
* {@link org.directwebremoting.guice.AbstractDwrModule#bindDwrScopes(boolean) bindDwrScopes(false)}
* accomplishes this.
*
* @author Tim Peierls [tim at peierls dot net]
*/
package org.directwebremoting.guice;