====== Java Plumbing ==

Step by step instructions of how to //build and run java code// as a normal application, as a java web start application and as an applet.

===== Deploy code both as Applet and Application ==

FIXME Replace with newer code and add file names!

It is [[javatut>deployment/webstart/developing.html|advisable]] to separate core functionality from the final deployment mechanism:

==== Appliction specific Code ==

<code java>
import javax.swing.*;

public class MyApplication extends JFrame {

    private void createAndShowGUI() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setTitle("My App Title");
        JPanel panel= new MyContent();  /* get app-specific content  */
        getContentPane().add(panel);    /* and put it into app frame */
        pack();
        setVisible(true);
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                MyApplication frame = new MyApplication();
                frame.createAndShowGUI();
            }
        });
    }
}
</code>

FIXME The usage of ''SwingUtilities.invokeLater'' is [[javatut>uiswing/start/compile.html|used]] by Sun as well.

==== Applet specific Code ==

<code java>
import javax.swing.*;

public class MyApplet extends JApplet {
    public void init() {
        try {
            SwingUtilities.invokeAndWait(new Runnable() {
                public void run() {
                    JPanel panel= new MyContent();/* create app-specific */
                    add(panel);     /* content and put it into app frame */
                }
            });
        } catch (Exception e) {
            System.err.println("createGUI didn't complete successfully");
        }
    }
}
</code>

==== Shared Code ==

<code java>
import javax.swing.*;

public class MyContent extends JPanel {
    private JLabel myLabel;

    MyContent() {
        myLabel= new JLabel("¡Hola Mundo!");
        add(myLabel);
    }
}
</code>

===== Separate code from generated classes ==

Structure:
  .
  |-- build
  |   `-- classes
  |       |-- PjpApplication.class
  |       `-- PropsPanel.class
  `-- src
      `-- pjp
          |-- PjpApplication.java
          `-- PropsPanel.java

The compile command is: (The destination path must exist!)
  javac -sourcepath src/pjp -d build/classes src/pjp/PjpApplication.java

The run command is:
  java -cp build/classes PjpApplication

===== Working with Packages ==

Structure:
  .
  |-- build
  |   `-- classes
  |       `-- pjp
  |           |-- PjpApplication.class
  |           `-- PropsPanel.class
  `-- src
      `-- pjp
          |-- PjpApplication.java
          `-- PropsPanel.java

Include ''package pjp;'' at the beginning of both source files.

<note important>The package statement must be the first line in the source file!</note>

The compile command is: (Note that the dir ''pjp'' in ''build/classes'' ist generated automatically)
  javac -sourcepath src -d build/classes/ src/pjp/PjpApplication.java

The run command is:
  java -cp build/classes pjp.PjpApplication

<note tip>Rule of thumb: The sourcepath, destinationpath and classpath statements end where the package statement starts</note>

[[javatut>/java/package/|More on packages]]

===== Create and use a Jar file ==

Create a dir for jar files: ''mkfile build/jar''

Add a manifest file, e.g. ''application.manifest'' and specify the main class as entry point:

  Main-Class: pjp.PjpApplication

Structure:
  .
  |-- application.manifest
  |-- build
  |   |-- classes
  |   `-- jar
  `-- src
      `-- pjp
          |-- PjpApplication.java
          `-- PropsPanel.java

Compile the sources like above and then create the jar file:
  jar cfm build/jar/pjpApplication.jar application.manifest -C build/classes .
''-C build/classes .'' means: Cd to build/classes and archive all files there. (Just type ''jar'' to get jar help)

The run command is:
  java -jar build/jar/pjpApplication.jar

===== Use Apache Ant for building ==

<code xml>
<project name="Pjp" default="maintarget">
    <property name="src.dir"     value="src"/>
    <property name="build.dir"   value="build"/>
    <property name="classes.dir" value="${build.dir}/classes"/>
    <property name="jar.dir"     value="${build.dir}/jar"/>
    <property name="application" value="${ant.project.name}Application"/>

    <target name="clean">
        <delete dir="${build.dir}"/>
    </target>

    <target name="compile">
        <mkdir dir="${classes.dir}"/>
        <javac srcdir="${src.dir}" destdir="${classes.dir}"/>
    </target>

    <target name="jar" depends="compile">
        <mkdir dir="${jar.dir}"/>
        <jar destfile="${jar.dir}/${application}.jar" basedir="${classes.dir}">
            <manifest>
                <attribute name="Main-Class" value="pjp.${application}"/>
            </manifest>
        </jar>
    </target>

    <target name="run" depends="jar">
        <java jar="${jar.dir}/${application}.jar" fork="true"/>
    </target>

    <target name="maintarget" depends="clean,run"/>
</project>
</code>

See also Tutorial: [[http://ant.apache.org/manual/tutorial-HelloWorldWithAnt.html|Hello World with Ant]]

===== Use Java Web Start ==

Project Structure:
  .
  |-- build.xml
  |-- jws.html
  |-- pjp-jws.jnlp
  `-- src
      `-- pjp
          |-- PjpApplet.java
          |-- PjpApplication.java
          `-- PropsPanel.java

pjp-jws.jnlp:
<code xml>
<?xml version="1.0" encoding="UTF-8"?>
<jnlp spec="1.0+"
    codebase="http://etb-111.kaeser-net.de/~becki/test/printJavaProps"
    href="pjp-jws.jnlp">
    <information>
        <title>Info Title</title>
        <vendor>Info Vendor</vendor>
    </information>
    <resources>
        <j2se version="1.6+" href="http://java.sun.com/products/autodl/j2se"/>
        <jar href="build/jar/PjpApplication.jar" main="true" />
    </resources>
    <application-desc
         name="application-desc name"
         main-class="pjp.PjpApplication"
         width="500"
         height="200">
     </application-desc>
     <update check="background"/>
</jnlp>
<xml>

jws.html contains:
<code html>
<a href="pjp-jws.jnlp">Launch Webstart Application</a>
</code>

FIXME

===== Create an Applet ==

Create ''applet.manifest'':
  Main-Class: pjp.PjpApplet

FIXME add Ant task

<code html>
<applet code="pjp.PjpApplet" archive="build/jar/pjpApplet.jar" width="500" height="200"></applet>
</code>

Note that there are [[javatut>deployment/applet/deployingApplet.html|more sophisticated ways]] to deploy an applet!

===== Using external Libs ==

FIXME http://ant.apache.org/manual/tutorial-HelloWorldWithAnt.html#ext-libs
FIXME http://ant.apache.org/manual/dirtasks.html (Manual -> Ant Tasks -> Core Tasks -> Concepts and Types -> Directory-based Tasks - How very easy to find!!)

===== Use Unit Tests ==

FIXME