Resolving DX Launch Issues on macOS (Java Compatibility)

Overview

This article explains how to fix DX (Data Exchange) failing to launch on macOS, particularly due to Java version conflicts, and how to set the correct Java environment.

1. Problem: DX Fails to Launch on macOS

✔ Observed Behavior:

• DX fails to start, showing a "Java Application launch failed" error.

• Running DX from the Terminal results in:

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  NoClassDefFoundError: javafx/application

• java -version reveals that Java 21 is installed instead of Java 8.

✔ Root Cause:

• DX requires Oracle Java 8.

• Newer macOS versions default to Java 21 if Java is updated via Homebrew or system updates.

• DX does not support Java 21 or newer versions.

2. Solution: Set Java 8 as the Default for DX

A. Verify Installed Java Versions

✔ Open Terminal and run:

bash

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/usr/libexec/java_home -V

✔ This lists all installed Java versions. Look for Java 8 in the output.

B. Temporarily Set Java 8 for DX

✔ If Java 8 is installed, set it before launching DX:

bash

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export JAVA_HOME=`/usr/libexec/java_home -v 1.8` java -jar <dx.jar>

✔ This command temporarily switches Java for the session.

C. Permanently Set Java 8 as Default (If Needed)

✔ If DX must always use Java 8, modify the .zshrc or .bash_profile:

bash

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echo 'export JAVA_HOME=`/usr/libexec/java_home -v 1.8`' >> ~/.zshrc source ~/.zshrc

✔ This ensures DX always launches with Java 8.

3. Alternative: Use a Virtual Machine

✔ If Java 8 is unavailable for Apple Silicon (M1, M2) Macs, DX must be run inside a Windows or Intel-based macOS VM.
✔ Use VMware Fusion, Parallels, or UTM to create a compatible macOS/Windows environment.

4. Best Practices for Running DX on macOS

✅ Always verify Java versions before launching DX (/usr/libexec/java_home -V).
✅ Use the correct Java version (Oracle Java 8), not OpenJDK or Java 21+.
✅ Set Java 8 temporarily or permanently for DX.
✅ Consider a VM for Apple Silicon (M1/M2) users.

5. Conclusion

• DX does not run on Java 21+ and requires Oracle Java 8.

• Users must manually set Java 8 before launching DX.

• Apple Silicon users may need a Windows/macOS VM to run DX.