2 Installing and Running Applications on the Raspberry Pi Board

Using the Java Runtime on the Raspberry Pi

There are several ways to use the Oracle Java ME Embedded platform on the Raspberry Pi board.

1. Directly run commands using an LXTerminal command-line shell interface or logging in using the ssh protocol.

2. Manually start a Developer Agent program on the desktop host and run commands using the Application Management System (AMS).

3. Run NetBeans IDE 8.0.

Running IMlets on Raspberry Pi Using the Command Shell

If you want to run IMlets directly on the Raspberry Pi board without a Developer Agent program, then you can use the commands shown in Table 2-1.

The following is a typical example of using the commands to install, list, run, and remove an Oracle Java ME Embedded application on the Raspberry Pi board. Note that the runSuite.sh shell command must be preceded by the sudo request to ensure that the command can run with superuser privileges and access all the peripherals on the board. Note also that either all commands must be preceded by the sudo request or none of them. Most commands can be terminated with the Ctrl-C key combination if they become unresponsive.

First, install the application using the installMidlet.sh command, specifying its location on the local file system.

pi@raspberrypi ~/bin $ sudo ./installMidlet.sh /home/pi/EmbeddedTestProject.jar
Java is starting. Press Ctrl+C to exit
The suite was successfully installed, ID: 2

After an IMlet is installed, note its ID: in this case, it is 2. Next, verify it using the listMidlets.sh command.

pi@raspberrypi ~/bin $ sudo ./listMidlets.sh 
Java is starting. Press Ctrl-C to exit
Suite: 2
  Name: EmbeddedTestProject
  Version: 1.0
  Vendor: Vendor
  MIDlets:
    MIDlet: GPIODemo

You can run any installed IMlet using the sudo runSuite.sh command. This command runs the IMlet that was just installed, passing any logging information to the standard output of this command. Note that you can press the Ctrl-C key to exit from this command, which will terminate the application.

pi@raspberrypi ~/bin $ sudo ./runSuite.sh 2 
Java is starting. Press Ctrl-C to exit
Starting - GPIODemo

You can use the removeMidlet.sh command to remove any installed IMlet.

pi@raspberrypi ~/bin $ sudo ./removeMidlet.sh 2
Java is starting. Press Ctrl-C to exit
Suite removed
pi@raspberrypi ~/bin $ 

You can verify the results by using the listMidlets.sh command.

pi@raspberrypi ~/bin $ sudo ./listMidlets.sh 
Java is starting. Press Ctrl-C to exit
No suites installed

Starting the Developer Agent Program on the Desktop

If you want to use the Developer Agent program, then extract files from the copy of the Oracle Java ME Embedded ZIP archive on the Windows desktop and delete the /appdb and the /bin directories. The Developer Agent program is a JAR file inside the util directory of the Oracle Java ME Embedded distribution, and is named proxy.jar. You can start the Developer Agent program on the desktop host computer either in a server or a client mode. After the Developer Agent program starts, use the AMS CLI.

Running IMlets on Raspberry Pi Using the AMS CLI

The next step is to make a raw connection to the AMS CLI. Note, however, you must first run the Developer Agent program on the desktop host and the Java runtime - on the Raspberry Pi board as described in Starting the Developer Agent Program on the Desktop unless the Developer Agent was started automatically by Java ME SDK.

At this point, you can start a PuTTY executable file on your desktop computer. Use this to create raw socket connections to the IP address of the host running the Developer Agent, and port 65002. For example, a connection to localhost and the port 65002 is shown in Figure 2-1.

Figure 2-1 Using PuTTY to Connect to the Command-Line Interface

Description of "Figure 2-1 Using PuTTY to Connect to the Command-Line Interface"

The window from port 65002 provides a CLI as shown in Figure 2-2.

Figure 2-2 Command-Line Interface to Raspberry Pi

Description of "Figure 2-2 Command-Line Interface to Raspberry Pi"

You can use the command-line interface to run the AMS commands shown in Table 2-2.

Here is a typical example of using the AMS to install, list, run, and remove an Oracle Java ME Embedded application on the board:

oracle>> ams-install file:///C:/some/directory/hello.jar hostdownload
<<ams-install,start install,file:///C:/some/directory/hello.jar
<<ams-install,install status: stage DONE, 0%
<<ams-install,install status: stage DONE, 100%
<<ams-install,OK,Install success

oracle>> ams-install http://www.example.com/netdemo.jar
<<ams-install,start install,http://www.example.com/netdemo.jar
<<ams-install,install status: stage DONE, 0%
<<ams-install,install status: stage DONE, 100%
<<ams-install,OK,Install success

oracle>> ams-install http://www.example.com/notthere.jar
<<ams-install,start install,http://www.example.com/notthere.jar
<<ams-install,FAIL,errorCode=103 (OTHER_ERROR)

Note that the final installation example failed with an error code and matching description.

Similarly, install an additional IMlet: rs232dem. After an IMlet is installed, verify it using the ams-list command. Each IMlet has been assigned a number by the AMS for convenience.

oracle>> ams-list
<<ams-list,0.hello|Oracle,STOPPED
<<ams-list,1.netdemo|Oracle,STOPPED
<<ams-list,2.rs232dem|Oracle,RUNNING
<<ams-list,OK,3 suites are installed

You can use the ams-remove command to remove any installed IMlet.

oracle>> ams-remove 0
<<ams-remove,OK,hello removed

The results can again be verified with the ams-list command.

oracle>> ams-list
<<ams-list,1.netdemo|Oracle,STOPPED
<<ams-list,2.rs232dem|Oracle,RUNNING
<<ams-list,OK,2 suites are installed

Finally, start the IMlet using the ams-run command. The application can be terminated with the ams-stop command.

oracle>> ams-run 1
<<ams-run,OK,started

oracle>> ams-list
<<ams-list,1.netdemo|Oracle,RUNNING
<<ams-list,2.rs232dem|Oracle,RUNNING
<<ams-list,OK,2 suites are installed

You can use the properties commands summarized in Table 2-3 and file system commands summarized in Table 2-4.

The CLI supports working with multiple devices. You can use the device commands summarized in Table 2-5.

You can use the keystore commands summarized in Table 2-6.

Using NetBeans with the Raspberry Pi Board

Running and debugging IMlet projects on the Raspberry Pi board using the NetBeans IDE 8.0 requires the following software:

• NetBeans IDE 8.0 with Java ME 8 support

• Oracle Java ME SDK 8.0

• Oracle Java ME SDK 8.0 plugins

For complete instructions about installing Oracle Java ME SDK 8.0, the NetBeans IDE 8.0, and Oracle Java ME SDK 8.0 plug-ins for NetBeans, see Oracle Java ME SDK Developer's Guide.

Adding the Raspberry Pi Board to the Device Connection Manager

Follow these steps to add the Raspberry Pi board to the Device Connections Manager in Oracle Java ME SDK 8.0:

1. Ensure that the sudo. /usertest.sh script in the /bin directory is running on the Raspberry Pi board.

2. Ensure that the Developer Agent program does not run on the desktop computer.

3. Start the Oracle Java ME SDK 8.0 Device Connections Manager (located at <SDK Installation Folder>/bin/device-manager.exe) and click its icon in the taskbar. A Device Connections Manager window is shown in Figure 2-3.

   Figure 2-3 Device Connections Manager Window

   
   Description of "Figure 2-3 Device Connections Manager Window"
   
   

4. Click the Add button, ensure that the IP Address or Host Name list contains the correct IP address of the Raspberry Pi board, and click OK.

5. After the Raspberry Pi board is registered, its IP address is listed on the Device Connections Manager list and its status is Connected as shown in Figure 2-4.

   Figure 2-4 Device Connections Manager Window with Raspberry Pi Connected

   
   Description of "Figure 2-4 Device Connections Manager Window with Raspberry Pi Connected"
   
   

Assigning the Raspberry Pi Board to Your Project

There are two ways to assign the Raspberry Pi board to your project:

• Using an existing NetBeans Project with an IMlet you want to run or debug.

• Creating a new NetBeans project.

After you assign the board to your project, clicking Run Project in the NetBeans IDE 8.0 runs your IMlets on the board instead of on the emulator.

package me8embeddedapplication1;
 
import jdk.dio.DeviceManager;
import jdk.dio.UnavailableDeviceException;
import jdk.dio.gpio.GPIOPin;
import java.io.IOException;import java.util.logging.Level;import java.util.logging.Logger;
import javax.microedition.midlet.*;
 
 
public class ME8EmbeddedApplication1 extends MIDlet {
 
    @Override
    public void startApp() {
        
        try {
            GPIOPin pin = (GPIOPin)DeviceManager.open(2);
            boolean b = pin.getValue();
        } catch (UnavailableDeviceException ex) {
        } catch (IOException ex) {
            Logger.getLogger(ME8EmbeddedApplication1.class.getName()).log(
Level.SEVERE, null, ex);
        }
        
    }
    
    public void pauseApp() {
    }
    
    public void destroyApp(boolean unconditional) {
    }
}

Debugging an IMlet on the Raspberry Pi Board

Follow these steps to debug an IMlet using NetBeans:

1. Open your IMlet class on the NetBeans editor.

2. Click once directly on the line number where you want to set a breakpoint. The line number is replaced by a red square and the line is highlighted in red.

3. Select Debug then Debug Project or use the Debug button on the toolbar.

The debugger connects to the debug agent on the board and the program stops at your breakpoint.

Accessing Peripherals

Applications that require access to Device I/O APIs must request appropriate permissions in JAD files. For more information about using the Device I/O APIs, see the Device I/O API 1.0 specification at:

http://docs.oracle.com/javame/8.0/api/dio/api/index.html