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Configure Your Java Environment

Before you can package MATLAB® functions into Java® applications or use the generated Java application in a Java development environment, you must ensure that your Java environment is properly configured. You should verify that:

  • Your system uses a version of the Java Developer’s Kit (JDK™) that is compatible with MATLAB.

  • JAVA_HOME is set to the folder containing the system’s JDK installation.

  • CLASSPATH contains all of the MATLAB library JAR files and the JAR files for the applications containing your packaged MATLAB code.

  • The MATLAB native library paths are properly configured.


For updated Java system requirements, including versions of Java Developer's Kit (JDK) and Java Runtime Environment (JRE), see the supported compiler page at

Install the Required JDK

To install the proper version of the JDK:

  1. Verify the version of Java your MATLAB installation is using by running the following MATLAB command:

    version -java
  2. Download a Java Developer's Kit (JDK) with the same major version from

  3. Install the JDK.


If you are not developing applications or compiling MATLAB code, you can use the Java Runtime Environment (JRE) instead of the JDK.


  1. Set the system environment variable, JAVA_HOME, to point to your JDK installation.

  2. At the MATLAB command prompt, type getenv JAVA_HOME to verify that MATLAB is reading the correct version of JAVA_HOME.

  3. Verify that the folder containing your Java installation has been added to your system PATH environment variable.


To build and run a Java application that uses a MATLAB Compiler SDK™ generated package, the system must locate:

  • JAR files containing the MATLAB libraries

  • Applications that you have developed and built with the compiler

Java classes generated by the MATLAB Compiler SDK software use classes contained in the com.mathworks.toolbox.javabuilder package. To use the compiled classes, you should include a file called javabuilder.jar on the Java class path. You can find this file in one of the following folders:

MATLAB installed on your systemmatlabroot/toolbox/javabuilder/jar
MATLAB Runtime installed on your systemmcrroot/toolbox/javabuilder/jar


matlabroot refers to the root folder into which the MATLAB installer has placed the MATLAB files. mcrroot refers to the root folder under which MATLAB Runtime is installed.

In addition, you should add to the JAR files created by the compiler to the class path.

Configure the Native Library Path Variables

The operating system uses the native library path to locate native libraries that are needed to run your Java class. See the following list of variable names according to operating system:

Windows® PATH

The native MATLAB or MATLAB Runtime files needed to execute the packaged MATLAB functions called from the Java code must be included on the paths listed by your system’s native library path variable.