To make sure that your projects have compatible versions of
Cloud Client Libraries, use the versions specified in the Google Cloud
Libraries Bill of Materials (BOM). The libraries in the BOM don't have
dependency conflicts that would manifest as NoSuchMethodError
or
NoClassDefFoundError
.
The BOM is necessary because Google publishes over two hundred open source Java libraries that make it easier to use services in Google Cloud. The Google Cloud libraries depend on several foundational libraries that can be used for general purposes.
These recommendations apply to the components of the following libraries:
Updating your project to use the BOM
To make sure that your projects uses compatible versions of the libraries
and their component artifacts, import com.google.cloud:libraries-bom
and use
the BOM to specify dependency versions. Be sure to remove any versions that you
set previously.
Maven
Import the BOM in the dependencyManagement
section of your pom.xml
file.
Include specific artifacts you depend on in the dependencies
section, but don't
specify the artifacts' versions in the dependencies
section. The example below
demonstrates how you would import the BOM and include the google-cloud-storage
artifact.
In this example, because the BOM manages library versions, the
version of google-cloud-storage
is omitted.
Gradle
BOMs are supported by default in Gradle 5.x or later. Add a platform
dependency on com.google.cloud:libraries-bom
and remove the version from the
dependency declarations in the artifact's build.gradle
file.
The platform
and enforcedPlatform
keywords supply dependency versions
declared in a BOM. The enforcedPlatform
keyword enforces the dependency
versions declared in the BOM and thus overrides what you specified.
For more details of the platform
and enforcedPlatform
keywords Gradle 5.x or higher, see
Gradle: Importing Maven BOMs.
If you're using Gradle 4.6 or later, add
enableFeaturePreview('IMPROVED_POM_SUPPORT')
to your settings.gradle
file.
For details, see
Gradle 4.6 Release Notes: BOM import.
Versions of Gradle earlier than 4.6 don't support BOMs.
SBT
SBT doesn't support BOMs. You can find recommended versions of libraries from a particular BOM version on the dashboard and set the versions manually.
Bazel
Bazel doesn't support BOMs. You can find recommended versions of libraries from a particular BOM version on the dashboard and set the versions manually.
Guava Versions -jre
or -android
Since the release of version 21.0.0, the Libraries BOM includes Guava's -jre
version (which supports Java 8+). The section below is not applicable for Java 8
users.
Google's Guava release contains two versions of artifacts:
"-jre" and "-android" versions.
The one with "-jre" (such as com.google.guava:guava:31.1-jre
) is
for Java 8 and supports lambda functions and streams.
The other version with the "-android" suffix (such as
com.google.guava:guava:31.1-android
) is for Java 7 and Android development.
The Google Cloud Libraries BOM contains Guava with the "-android" version
to make sure that the BOM works in Java 7. However, this means the version of
Guava in the BOM doesn't have some methods that are intended for Java 8 lambda
functions, such as ImmutableList.toImmutableList()
.
If your project requires Java 8 or later and uses Guava classes
such as com.google.common.collect.Streams
, you should add a dependency on a
JRE version of Guava.
In Maven:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>31.1-jre</version> <!-- "-jre" for Java 8 or higher -->
</dependency>
</dependencies>
<dependencies>
<dependency>
<groupId>com.google.cloud</groupId>
<artifactId>libraries-bom</artifactId>
...
</dependencyManagement>
In Gradle:
dependencies {
constraints {
implementation 'com.google.guava:guava:31.1-jre' // "-jre" for Java 8 or higher
}
implementation platform('com.google.cloud:libraries-bom:26.12.0')
...
}
The previous sample doesn't work if you use enforcedPlatform
because
enforcedPlatform
takes precedence over constraints
. If you want to use
enforcedPlatform
with the Guava version, you can configure
ResolutionStrategy
.