How Can I Determine My JVM's Bitness from Within a Java Program?

Determining JVM Bitness within a Java Program

Understanding the bitness of the JVM your application runs on is crucial for performance and compatibility. To ascertain this information from within your program, you have several options depending on your Java version.

Java Versions 7-9

Java versions 7 to 9 introduced specific flags for checking JVM bitness:

• -d32: Use a 32-bit data model if available
• -d64: Use a 64-bit data model if available

To check for a 64-bit JVM, execute:

java -d64 -version

If it's not available, you'll encounter an error indicating so. Similarly, you can check for a 32-bit JVM using -d32.

Post-Java 9 Versions

In Java 9 and later, the -d32 and -d64 flags have been deprecated and removed, respectively. Therefore, modern versions of Java do not provide built-in methods within the program to determine JVM bitness.

However, you can still check the JVM bitness using command-line flags:

• Command Prompt:

  java -XshowSettings:vm

• Terminal:

  java -version -verbosegc -XX:+PrintFlagsFinal | grep Bits

You should see the output 32-bit or 64-bit, indicating the JVM's data model.

The above is the detailed content of How Can I Determine My JVM's Bitness from Within a Java Program?. For more information, please follow other related articles on the PHP Chinese website!