Cannot run Launch4j (illegal access)

Question

I would like to create an .exe file for my java desktop application. Hence, i saw that Launch4j was the best option.

When I ran. the file, i have the following error message.

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.thoughtworks.xstream.core.util.Fields (file:/usr/local/Cellar/launch4j/3.12/libexec/lib/xstream.jar) to field java.util.Properties.defaults
WARNING: Please consider reporting this to the maintainers of com.thoughtworks.xstream.core.util.Fields
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/java/swing/plaf/windows/WindowsLookAndFeel
    at java.base/java.lang.ClassLoader.defineClass1(Native Method)
    at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1017)
    at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:174)
    at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:800)
    at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:698)
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:621)
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579) 
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) 
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522) 
    at net.sf.launch4j.Main.main(Main.java:59) Caused by: java.lang.ClassNotFoundException: com.sun.java.swing.plaf.windows.WindowsLookAndFeel 
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)   
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)  ... 10 more

I am working under Mac OS Catalina, version 10.15.3. and my Java version environment: openjdk version "11.0.7" 2020-04-14 OpenJDK Runtime Environment AdoptOpenJDK (build 11.0.7+10) OpenJDK 64-Bit Server VM AdoptOpenJDK (build 11.0.7+10, mixed mode)

If you have any other program that could do the job, i'll be glad to know. In fact, i am looking for something equivalent to InnoSetup for both OS (Windows and Mac)

Thank you for the help

Answer 1

I had this same error and found your question looking for a solution.

I ended up getting launch4j running by downloading openJDK 9.0.4 from the archive at https://jdk.java.net/archive/.

Running the launch4j.jar manually with this java version worked as expected:

jdk-9.0.4.jdk/Contents/Home/bin/java -jar ~/Downloads/launch4j/launch4j.jar 

Answer 2

If you are using java 11 and using Linux, download and install another java version. I installed java 8.

Run the command "sudo update-alternatives --config java" to list all the java versions installed in your computer. The command will provide an option to change the default java version.

Change from 11 to 8(Am not sure if any other version will work).

Rerun the command java -jar launch4j. It should work