Tutorial of Java2Script SWT and Simple RPC Application

In this article, I will show you a simple example using Java2Script Simple RPC (For "what is Java2Script Simple RPC? ", please read this post).

Step 1. Create a Java2Script Servlet Project

Here are instructions: File -> New -> Project ... -> Java2Script -> Java2Script Servlet Proejct -> Next -> Key in project name and select "Create separate folders for sources and class files" -> Next or Finish or Finish on next page

When finish this step, try to expand the project sources, you should get similar structures as below:

Later, I will explain more about every files.

Step 2. Create an SWT Application

Here are instructions: Select "src" source folder and create package named "org.java2script.demo.simplerpc", and create a class name "SimpleSWTRPC" in that package. The class' source is as following:

package org.java2script.demo.simplerpc;

import net.sf.j2s.ajax.SimpleRPCSWTRequest;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

public class SimpleSWTRPC extends Shell {

private Text responseText;
private Text requestText;
private Label statusLabel;
/**
* Launch the application
* @param args
*/
public static void main(String args[]) {
try {
Display display = Display.getDefault();
SimpleSWTRPC shell = new SimpleSWTRPC(display, SWT.SHELL_TRIM);
shell.open();
shell.layout();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
} catch (Exception e) {
e.printStackTrace();
}
}

/**
* Create the shell
* @param display
* @param style
*/
public SimpleSWTRPC(Display display, int style) {
super(display, style);
createContents();
setLayout(new FillLayout());
}

/**
* Create contents of the window
*/
protected void createContents() {
setText("Hello SWT & Simple RPC");
setSize(371, 300);

final Composite composite = new Composite(this, SWT.NONE);
composite.setLayout(new GridLayout());

final Label requestLabel = new Label(composite, SWT.NONE);
final GridData gd_requestLabel = new GridData(SWT.FILL, SWT.CENTER, true, false);
requestLabel.setLayoutData(gd_requestLabel);
requestLabel.setText("Request:");

requestText = new Text(composite, SWT.MULTI | SWT.BORDER);
final GridData gd_requestText = new GridData(SWT.FILL, SWT.FILL, true, true);
gd_requestText.heightHint = 80;
gd_requestText.minimumHeight = 80;
requestText.setLayoutData(gd_requestText);

final Button sendButton = new Button(composite, SWT.NONE);
sendButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
statusLabel.setText("Sending request ...");
String text = requestText.getText();
text = "[Server echo]:" + text;
responseText.setText(text);
statusLabel.setText("Server responded.");
}
});
final GridData gd_sendButton = new GridData(SWT.RIGHT, SWT.CENTER, false, false);
sendButton.setLayoutData(gd_sendButton);
sendButton.setText("Send Simple RPC Request");

final Label reponseLabel = new Label(composite, SWT.NONE);
reponseLabel.setText("Reponse:");

responseText = new Text(composite, SWT.MULTI | SWT.READ_ONLY | SWT.BORDER);
final GridData gd_responseText = new GridData(SWT.FILL, SWT.FILL, true, true);
gd_responseText.heightHint = 80;
responseText.setLayoutData(gd_responseText);

statusLabel = new Label(composite, SWT.BORDER);
final GridData gd_statusLabel = new GridData(SWT.FILL, SWT.CENTER, true, false);
statusLabel.setLayoutData(gd_statusLabel);
statusLabel.setText("...");
//
}

@Override
protected void checkSubclass() {
// Disable the check that prevents subclassing of SWT components
}

}

I used Instantiations' WindowBuilder Pro (also known as SWT Designer) to generate the above codes. I only wrote a few lines as:

sendButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
statusLabel.setText("Sending request ...");
String text = requestText.getText();
text = "[Server echo]:" + text;
responseText.setText(text);
statusLabel.setText("Server responded.");
}
});

Step 3. Run as Java Application and Java2Script.

Use context menu to "Run as" -> Java Application, and "Run as" -> Java2Script Application. You should get things work.

Step 4. Add Simple RPC into Example

Now it is time to move

text = "[Server echo]:" + text;

to the server side.

First, create a new EchoRunnable class extending net.sf.j2s.ajax.SimpleRPCRunnable as follow:

package org.java2script.demo.simplerpc;

import net.sf.j2s.ajax.SimpleRPCRunnable;

public class EchoRPCRunnable extends SimpleRPCRunnable {

public String text;

public void ajaxRun() {
text = "[Server echo]:" + text;
}

}

Then modify button's event handler as follow:

sendButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
statusLabel.setText("Sending request ...");
SimpleRPCSWTRequest.swtRequest(new EchoRPCRunnable() {

public void ajaxIn() {
text = requestText.getText();;
}

public void ajaxOut() {
responseText.setText(text);
statusLabel.setText("Server responded.");
}

public void ajaxFail() {
statusLabel.setText("Request failed.");
}

});
}
});

Re-test the application in native Java SWT application mode. It should work as expected.

Step 5.? Deploy Java2Script Simple RPC Application

Open WEB-INF/web.xml and add org.java2script.demo.simplerpc.EchoRunnable to simple.rpc.runnables list. Here is the web.xml:

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
<display-name>Java2Script</display-name>
<description>Java2Script application</description>
<servlet>
<servlet-name>simplerpc</servlet-name>
<servlet-class>net.sf.j2s.ajax.SimpleRPCHttpServlet</servlet-class>
<init-param>
<param-name>simple.rpc.runnables</param-name>
<!--
Qualified names of inherited net.sf.j2s.ajax.SimpleRPCRunnable
classes, seperated by ";".
-->
<param-value>
org.java2script.demo.simplerpc.EchoRPCRunnable
</param-value>
</init-param>
<init-param>
<param-name>simple.rpc.xss.support</param-name>
<param-value>true</param-value>
</init-param>
<!--
<init-param>
<param-name>simple.rpc.post.limit</param-name>
<param-value>16777216</param-value>
</init-param>
<init-param>
<param-name>simple.rpc.xss.max.parts</param-name>
<param-value>8</param-value>
</init-param>
<init-param>
<param-name>simple.rpc.xss.max.latency</param-name>
<param-value>6000</param-value>
</init-param>
-->
</servlet>
<servlet-mapping>
<servlet-name>simplerpc</servlet-name>
<url-pattern>/simplerpc</url-pattern>
</servlet-mapping>
</web-app>

Select build.xml file, right click to bring up context-menu and "Run as" -> Ant Build, and then select the project and right click and select "Refresh" to refresh the project files, you will see a "org.java2script.demo.simplerpc.war" file. Now try to deploy this war file to a Java servlet container, such as Tomcat server.

If your Tomcat? server is installed in localhost, try url:

http://localhost:8080/manager/html

to deploy the above mentioned war file.

But you haven't finish deployment yet, because you still need to deploy Java2Script's core *.js library files to the server.

Add the following to build.xml:

<target name="pack.plugins.j2slib.war">
<delete file="${basedir}/../plugins.war" quiet="true"/>
<zip destfile="${basedir}/../plugins.war">
<fileset dir="${basedir}/../../../plugins/">
<include name="net.sf.j2s.lib_1.0.0/**"/>
<exclude name="net.sf.j2s.lib_1.0.0/library.jar"/>
<exclude name="net.sf.j2s.lib_1.0.0/plugin.xml"/>
<exclude name="net.sf.j2s.lib_1.0.0/META-INF/**"/>
</fileset>
</zip>
</target>

And "Run as" -> "Ant Build ...", select "pack.plugins.j2slib.war" in the "Targets" tab and "Run". Then refresh the project, and deploy the "plugins.war" to Tomcat server.

And after all things deployed, please visit:

http://localhost:8080/org.java2script.demo.simplerpc/org.java2script.demo.simplerpc.SimpleSWTRPC.html

Here is the online demo of this Simple RPC example.

(To be continued)