bGwtGson

A library that allows using GWT with Gson

Download

Download from here then add to your build path.

Setup

Step 1: Add Gson to your lib folder

Download Gson then add to you WEB-INF/lib folder.

Step 2: Module

Add this to your Module.gwt.xml:

<inherits name="com.sangnd.gwt.gson.GwtGson" />

Step 3: Web.xml

Add this to your web.xml:

<servlet>
	<servlet-name>GwtGsonService</servlet-name>
	<servlet-class>com.sangnd.gwt.gson.server.GwtGsonServiceImpl</servlet-class>
</servlet>
<servlet-mapping>
	<servlet-name>GwtGsonService</servlet-name>
	<url-pattern>/YourProjectPath/gwtGsonService</url-pattern>
</servlet-mapping>

Usage

Your object class must be implemented IsSerializable interface like this example.

Create GwtGsonServiceAsync instance:

GwtGsonServiceAsync gwtGsonService = GWT.create(GwtGsonService.class);

From object to Json string

Example:

gwtGsonService.toJson(new Car("Ferari", "Red", 11111), new AsyncCallback<String>() {

  				@Override
					public void onFailure(Throwable caught) {
					}

					@Override
					public void onSuccess(String result) {
						System.out.println("Result is: " + result);
					}
				});

Output:

Result is: {"name":"Ferari","color":"Red","value":11111}

From Json string to object

Assume that json is a String with value: {"name":"Ferari","color":"Red","value":11111}

Example:

gwtGsonService.fromJson(json, new Car(), new AsyncCallback<IsSerializable>() {

  @Override
  public void onFailure(Throwable caught) {
  }
  
  @Override
  public void onSuccess(IsSerializable result) {
  	if (result != null && result instanceof Car) {
  		Car u = (Car) result;
  		System.out.println("Car's name is: " + u.getName());
  		
  	} else {
  		System.out.println("null");
  	}
  	
  }
});

Output:

Car's name is: Ferari

As you see, we must send a "empty" instance of Car to send object type via RPC. If you know the more effective way to do this, send me a pull request.

Author

• heroandtn3

License

Copyright (c) 2013 heroandtn3.

Licensed under the GNU General Public License. See COPYING for details.