- V2 supports custom distributions and provides support for Azul Zulu OpenJDK, Eclipse Temurin and AdoptOpenJDK out of the box. V1 supports only Azul Zulu OpenJDK.
- V2 requires you to specify distribution along with the version. V1 defaults to Azul Zulu OpenJDK, only version input is required. Follow [the migration guide](docs/switching-to-v2.md) to switch from V1 to V2.
-`java-version`: The Java version that is going to be set up. Takes a whole or [semver](#supported-version-syntax) Java version. If not specified, the action will expect `java-version-file` input to be specified.
-`java-version-file`: The path to a file containing java version. Supported file types are `.java-version` and `.tool-versions`. See more details in [about .java-version-file](docs/advanced-usage.md#Java-version-file).
-`architecture`: The target architecture of the package. Possible values: `x86`, `x64`, `armv7`, `aarch64`, `ppc64le`. Default value: Derived from the runner machine.
-`jdkFile`: If a use-case requires a custom distribution setup-java uses the compressed JDK from the location pointed by this input and will take care of the installation and caching on the VM.
-`cache`: Quick [setup caching](#caching-packages-dependencies) for the dependencies managed through one of the predefined package managers. It can be one of "maven", "gradle" or "sbt".
-`cache-dependency-path`: The path to a dependency file: pom.xml, build.gradle, build.sbt, etc. This option can be used with the `cache` option. If this option is omitted, the action searches for the dependency file in the entire repository. This option supports wildcards and a list of file names for caching multiple dependencies.
The action has a bunch of inputs to generate maven's [settings.xml](https://maven.apache.org/settings.html) on the fly and pass the values to Apache Maven GPG Plugin as well as Apache Maven Toolchains. See [advanced usage](docs/advanced-usage.md) for more.
**NOTE:** The different distributors can provide discrepant list of available versions / supported configurations. Please refer to the official documentation to see the list of supported versions.
**NOTE:** AdoptOpenJDK got moved to Eclipse Temurin and won't be updated anymore. It is highly recommended to migrate workflows from `adopt` and `adopt-openj9`, to `temurin` and `semeru` respectively, to keep receiving software and security updates. See more details in the [Good-bye AdoptOpenJDK post](https://blog.adoptopenjdk.net/2021/08/goodbye-adoptopenjdk-hello-adoptium/).
The action has a built-in functionality for caching and restoring dependencies. It uses [toolkit/cache](https://github.com/actions/toolkit/tree/main/packages/cache) under hood for caching dependencies but requires less configuration settings. Supported package managers are gradle, maven and sbt. The format of the used cache key is `setup-java-${{ platform }}-${{ packageManager }}-${{ fileHash }}`, where the hash is based on the following files:
When the option `cache-dependency-path` is specified, the hash is based on the matching file. This option supports wildcards and a list of file names, and is especially useful for monorepos.
The workflow output `cache-hit` is set to indicate if an exact match was found for the key [as actions/cache does](https://github.com/actions/cache/tree/main#outputs).
Usually, cache gets downloaded in multiple segments of fixed sizes. Sometimes, a segment download gets stuck, which causes the workflow job to be stuck. The cache segment download timeout [was introduced](https://github.com/actions/toolkit/tree/main/packages/cache#cache-segment-restore-timeout) to solve this issue as it allows the segment download to get aborted and hence allows the job to proceed with a cache miss. The default value of the cache segment download timeout is set to 10 minutes and can be customized by specifying an environment variable named `SEGMENT_DOWNLOAD_TIMEOUT_MINS` with a timeout value in minutes.
In the basic examples above, the `check-latest` flag defaults to `false`. When set to `false`, the action tries to first resolve a version of Java from the local tool cache on the runner. If unable to find a specific version in the cache, the action will download a version of Java. Use the default or set `check-latest` to `false` if you prefer a faster more consistent setup experience that prioritizes trying to use the cached versions at the expense of newer versions sometimes being available for download.
If `check-latest` is set to `true`, the action first checks if the cached version is the latest one. If the locally cached version is not the most up-to-date, the latest version of Java will be downloaded. Set `check-latest` to `true` if you want the most up-to-date version of Java to always be used. Setting `check-latest` to `true` has performance implications as downloading versions of Java is slower than using cached versions.
For Java distributions that are not cached on Hosted images, `check-latest` always behaves as `true` and downloads Java on the fly. Check out [Hosted Tool Cache](docs/advanced-usage.md#Hosted-Tool-Cache) for more details about pre-cached Java versions.
All versions are added to the PATH. The last version will be used and available globally. Other Java versions can be accessed through env variables with such specification as 'JAVA_HOME_{{ MAJOR_VERSION }}_{{ ARCHITECTURE }}'.
In the example above multiple JDKs are installed for the same job. The result after the last JDK is installed is a Maven Toolchains declaration containing references to all three JDKs. The values for `id`, `version`, and `vendor` of the individual Toolchain entries are the given input values for `distribution` and `java-version` (`vendor` being the combination of `${distribution}_${java-version}`) by default.
