src/site/apt/examples/targetJdk.apt.vm

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 Target JDK and Toolchains
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 Dennis Lundberg
 Andreas Dangel
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 2020-10-02
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 ~~ Licensed to the Apache Software Foundation (ASF) under one
 ~~ or more contributor license agreements.  See the NOTICE file
 ~~ distributed with this work for additional information
 ~~ regarding copyright ownership.  The ASF licenses this file
 ~~ to you under the Apache License, Version 2.0 (the
 ~~ "License"); you may not use this file except in compliance
 ~~ with the License.  You may obtain a copy of the License at
 ~~
 ~~   http://www.apache.org/licenses/LICENSE-2.0
 ~~
 ~~ Unless required by applicable law or agreed to in writing,
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 ~~ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 ~~ KIND, either express or implied.  See the License for the
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~~ http://maven.apache.org/doxia/references/apt-format.html

Target JDK

 There is a configuration element in the PMD plugin that lets you set which
 {{{../pmd-mojo.html#targetJdk}target JDK}} your Java code will be compiled for.
 Often you want this to be in sync with the configuration for maven-compiler-plugin.
 The best practice for this is to set up the wellknown property <<<maven.compiler.target>>>
 and the rest will work automatically. Alternatively, you can set it manually:

+--------------------+
<project>
  ...
  <reporting>
    <plugins>
      <plugin>
        <artifactId>maven-pmd-plugin</artifactId>
        <version>${project.version}</version>
        <configuration>
          <targetJdk>1.6</targetJdk>
        </configuration>
      </plugin>
    </plugins>
  </reporting>
  ...
</project>
+--------------------+

Using Maven Toolchains

 Since version 3.14.0 of the PMD plugin, toolchains are supported. This helps if the build system is
 running a different JDK than being used for compiling. PMD reads the class files for
 {{{../pmd-mojo.html#typeResolution}type resolution}} and this fails with ClassFormatErrors
 if the JDK version is incorrect.

 To set this up, refer to the {{{/guides/mini/guide-using-toolchains.html}Guide to Using Toolchains}}, which makes use
 of the {{{/plugins/maven-toolchains-plugin/}Maven Toolchains Plugin}}.

 With the maven-toolchains-plugin you configure 1 default JDK toolchain for all related maven-plugins.
 Since maven-pmd-plugin 3.14.0 when using with Maven 3.3.1+ it is also possible to give the plugin its own
 toolchain, which can be useful in case of different JDK calls per execution block (e.g. the test sources require a
 different JDK compared to the main sources).