KOS Developer's Portal

Ref: Java Debugging Details

Introduction

This article shows how to set up your IDE so that you can debug (run, hit breakpoints, single step, examine variables) your KOS backend Java code.

While these specific instructions are for IntelliJ and Eclipse, you can follow these same general steps if you use another IDE.

Overview

KOS gives you the ability to debug your Java code. It works whether the target system is a simulator or actual hardware.

The primary component, the "KOS Debug JRE", sits between your IDE, your running KOS Studio, and the target system.

The following diagram illustrates the interactions that occur during the debug process:

Figure 1. Overview of Java debugging

The rest of this article explains how you set up and use the KOS Debug JRE.

IntelliJ

Follow these steps when using the IntelliJ IDE. The instructions are basically the same for Linux, Mac, and Windows.

1) Run/Debug Configurations

Open the "Run/Debug Configurations" dialog.

Figure 2. IntelliJ run/debug configuration

2) Alternative JRE

In the "Run" section, click to select an alternative JRE

Figure 3. Select alternative JRE

3) Select JRE

Navigate to and then select the special KOS debug JRE.

Location of JRE files

The KOS JRE files are stored at different locations, depending on the operating system.

MacOS   : $USER_HOME/Applications/kosStudio.app/Contents/MacOS/tools/kos-debug-jre
Windows : $INSTALL_DIR/kosStudio/release/tools/kos-debug-jre

Here’s the Windows JRE picker:

Figure 4. Directory of alternative JRE

Here’s the Mac JRE picker:

Figure 5. Mac JRE picker

4) Finish

After selecting the alternative JRE, the following appears.

Figure 6. Debug JRE configuration complete

Notice that the JRE has changed. Click OK to close this window.

Debug Instructions

Details about how to fill in the main class and command line arguments are covered in the How To Debug Code tutorial.

Eclipse

Follow these steps when using the Eclipse IDE. The instructions are basically the same for Linux, Mac, and Windows.

1) Debug Configurations

Open the "Debug Configurations" dialog and then click the "JRE" tab.

Figure 7. Eclipse run/debug configuration

2) Alternate JRE

Select "Alternate JRE" and then click the "Installed JREs…" button.

Figure 8. Select alternative JRE

3) Preferences

In the "Preferences" dialog, click the "Add…" button.

Figure 9. Installed JREs

4) Add JRE

In the "Add JRE" dialog, select "Standard VM" and click "Next".

Figure 10. Add new JRE

5) Pick JRE

Click "Directory" and then navigate to and select the KOS JRE directory.

Location of JRE files

The KOS JRE files are stored at different locations, depending on the operating system.

MacOS   : $USER_HOME/Applications/kosStudio.app/Contents/MacOS/tools/kos-debug-jre
Windows : $INSTALL_DIR/kosStudio/release/tools/kos-debug-jre

Here’s the Windows JRE picker:

Figure 11. Windows JRE picker

Here’s the Mac JRE picker:

Figure 12. Mac JRE selector

6) JRE Added

Click "Finish" and ensure that the primary JRE is still the "default".

Figure 13. Debug JRE is ready

7) Select KOS JRE

Click "Apply and Close" and ensure that the "kos-debug-jre" is selected as the alternate JRE.

Figure 14. Select special debug JRE

You can now click "Close" to save this configuration. Click "Debug" when ready to run the application.

Conclusion

In this article you learned how to configure your Java IDE to enable debugging.

Check out the How To Debug Code tutorial to find out how to actually debug your code.