The Java Developers Almanac 1.4

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e104. Enabling Assertions from the Command Line

The command line options -ea and -da allow you to enable and disable assertion in a package subtree or in a class. Here are several examples of the switches. Enable assertions in all non-system classes:

    java -ea MyApp

Enable assertions in all classes in the unnamed package:

    java -ea:... MyApp

Enable assertions in all classes in a package subtree:

    java -ea:com.mycompany... MyApp

Enable assertions in a particular class:

    java -ea:com.mycompany.MyCompany MyApp

Disable assertions in all classes in a package subtree:

    java -da:com.mycompany... MyApp

Disable assertions in a particular class:

    java -da:com.mycompany.MyClass MyApp

Multiple assertion switches on the command line are processed from left to right. Enable assertions in all classes in a package subtree except for one class:

    java -ea:com.mycompany... -da:com.mycompany.MyClass MyApp

Related Examples

e103. Compiling a Program with Assertions
e105. Handling an Assertion Error

See also: Arrays Classes Commands Numbers Objects Strings System Properties Threads

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