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Support Article

"Could not initialize class" error when checking in UI rules



User is getting an error when checking in section rules that contain small image icons.

Error Messages

Could not initialize class sun.awt.X11.xToolkit.
Stack Trace:
Caused by: java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11.XToolkit at java.lang.Class.forName0(Native Method) at java.lang.Class.forName( at java.awt.Toolkit$ at Method) at java.awt.Toolkit.getDefaultToolkit( at javax.swing.ImageIcon.<init>( at com.pegarules.generated.html_fragment.ra_stream_pzcontroliconreadonly_a671f1ee5073efce688dadb0dba60368

Root Cause

Misconfiguration in user’s JVM argument.


Configure below settings in JVM to resolve the issue:
Define JVM argument in setEnv script file as below.
set JAVA_OPTS=-Xms1024m -Xmx2048m -XX:PermSize=64m -XX:MaxPermSize=384m -Djava.awt.headless=true


Published June 12, 2015 - Updated October 8, 2020

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