Guava: Google Core Libraries for Java

Guava is a set of core libraries that includes new collection types (such as multimap and multiset), immutable collections, a graph library, functional types, an in-memory cache, and APIs/utilities for concurrency, I/O, hashing, primitives, reflection, string processing, and much more!

Requires JDK 1.6 or higher. The coming release (21.0) will require JDK 1.8, but we will begin providing a backport soon thereafter.

Latest release

The most recent release is Guava 20.0, released October 28, 2016.

• 20.0 API Docs: guava, guava-testlib
• 20.0 API Diffs from 19.0: guava

To add a dependency on Guava using Maven, use the following:

<dependency>
  <groupId>com.google.guava</groupId>
  <artifactId>guava</artifactId>
  <version>20.0</version>
</dependency>

To add a dependency using Gradle:

dependencies {
  compile 'com.google.guava:guava:20.0'
}

Upcoming release

Guava 21.0-rc1 was released December 19, 2016. This release requires Java 8.

Snapshots

Snapshots of Guava built from the master branch are available through Maven using version 21.0-SNAPSHOT. API documentation and diffs from version 20.0 are available here:

• Snapshot API Docs: guava
• Snapshot API Diffs from 20.0: guava

Learn about Guava

• Our users' guide, Guava Explained
• A nice collection of other helpful links

Links

• GitHub project
• Issue tracker: Report a defect or feature request
• StackOverflow: Ask "how-to" and "why-didn't-it-work" questions
• guava-discuss: For open-ended questions and discussion

IMPORTANT WARNINGS

1. APIs marked with the @Beta annotation at the class or method level are subject to change. They can be modified in any way, or even removed, at any time. If your code is a library itself (i.e. it is used on the CLASSPATH of users outside your own control), you should not use beta APIs, unless you repackage them (e.g. using ProGuard).

2. Deprecated non-beta APIs will be removed two years after the release in which they are first deprecated. You must fix your references before this time. If you don't, any manner of breakage could result (you are not guaranteed a compilation error).

3. Serialized forms of ALL objects are subject to change unless noted otherwise. Do not persist these and assume they can be read by a future version of the library.

4. Our classes are not designed to protect against a malicious caller. You should not use them for communication between trusted and untrusted code.

5. We unit-test and benchmark the libraries using only OpenJDK 1.7 on Linux. Some features, especially in com.google.common.io, may not work correctly in other environments.