IBM Support

How can I use the _JAVA_LAUNCHER_DEBUG environment variable to get debug information from the Java launcher?

Question & Answer


Question

How can I use the _JAVA_LAUNCHER_DEBUG environment variable to get debug information from the Java™ launcher?

Answer

When you run a Java program from the command line, you can pass additional options to the Java launcher program, which starts the Java virtual machine (VM). If you set the environment variable _JAVA_LAUNCHER_DEBUG=true before you run your application you can obtain some debug information from the launcher. 
On Unix systems, set this environment variable by running the following command in a terminal window:
export _JAVA_LAUNCHER_DEBUG=true
On Windows, you can use the System Properties Environment Variables dialog, or run the following command at a Windows command prompt: 
set _JAVA_LAUNCHER_DEBUG=true
Then, run your Java application to obtain debug output from the Java launcher. The following examples start your Java application with the shared classes cache enabled. 
On Unix systems:
~temp/jre/bin/java -Xshareclasses MyJavaClass
On Windows systems:
c:\temp\jre\bin\java.exe -Xshareclasses MyJavaClass
Although the format of the output might change from one Java version to another, the output typically shows how the Java launcher processes the initial options that it passes to the Java VM, and the location of the libraries that are used to launch the Java VM.

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSNVBF","label":"Runtimes for Java Technology"},"Component":"Java launcher","Platform":[{"code":"PF002","label":"AIX"},{"code":"PF016","label":"Linux"},{"code":"PF033","label":"Windows"},{"code":"PF035","label":"z\/OS"}],"Version":"All Versions","Edition":"","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
23 September 2019

UID

ibm11074394