FindJava

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Cmake/docs/3.21/module/findjava


FindJava

Find Java

This module finds if Java is installed and determines where the include files and libraries are. The caller may set variable JAVA_HOME to specify a Java installation prefix explicitly.

See also the FindJNI module to find Java Native Interface (JNI).

New in version 3.10: Added support for Java 9+ version parsing.


Specify one or more of the following components as you call this find module. See example below.

Runtime     = Java Runtime Environment used to execute Java byte-compiled applications
Development = Development tools (java, javac, javah, jar and javadoc), includes Runtime component
IdlJ        = Interface Description Language (IDL) to Java compiler
JarSigner   = Signer and verifier tool for Java Archive (JAR) files

This module sets the following result variables:

Java_JAVA_EXECUTABLE      = the full path to the Java runtime
Java_JAVAC_EXECUTABLE     = the full path to the Java compiler
Java_JAVAH_EXECUTABLE     = the full path to the Java header generator
Java_JAVADOC_EXECUTABLE   = the full path to the Java documentation generator
Java_IDLJ_EXECUTABLE      = the full path to the Java idl compiler
Java_JAR_EXECUTABLE       = the full path to the Java archiver
Java_JARSIGNER_EXECUTABLE = the full path to the Java jar signer
Java_VERSION_STRING       = Version of java found, eg. 1.6.0_12
Java_VERSION_MAJOR        = The major version of the package found.
Java_VERSION_MINOR        = The minor version of the package found.
Java_VERSION_PATCH        = The patch version of the package found.
Java_VERSION_TWEAK        = The tweak version of the package found (after '_')
Java_VERSION              = This is set to: $major[.$minor[.$patch[.$tweak]]]

New in version 3.4: Added the Java_IDLJ_EXECUTABLE and Java_JARSIGNER_EXECUTABLE variables.


The minimum required version of Java can be specified using the find_package() syntax, e.g.

find_package(Java 1.8)

NOTE: ${Java_VERSION} and ${Java_VERSION_STRING} are not guaranteed to be identical. For example some java version may return: Java_VERSION_STRING = 1.8.0_17 and Java_VERSION = 1.8.0.17

another example is the Java OEM, with: Java_VERSION_STRING = 1.8.0-oem and Java_VERSION = 1.8.0

For these components the following variables are set:

Java_FOUND                    - TRUE if all components are found.
Java_<component>_FOUND        - TRUE if <component> is found.

Example Usages:

find_package(Java)
find_package(Java 1.8 REQUIRED)
find_package(Java COMPONENTS Runtime)
find_package(Java COMPONENTS Development)

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Licensed under the BSD 3-clause License.
https://cmake.org/cmake/help/v3.21/module/FindJava.html