Set up an Apache Maven project
You can use Apache Maven
Prerequisites
To use the Amazon SDK for Java with Maven, you need the following:
-
Java 8.0 or later. You can download the latest Java SE Development Kit software from http://www.oracle.com/technetwork/java/javase/downloads/
. The Amazon SDK for Java also works with OpenJDK and Amazon Corretto, a distribution of the Open Java Development Kit (OpenJDK). Download the latest OpenJDK version from https://openjdk.java.net/install/index.html . Download the latest Amazon Corretto 8 or Amazon Corretto 11 version from the Corretto page . -
Apache Maven. If you need to install Maven, go to http://maven.apache.org/
to download and install it.
Create a Maven project
To create a Maven project from the command line, run the following command from a
terminal or command prompt window.
mvn -B archetype:generate \ -DarchetypeGroupId=software.amazon.awssdk \ -DarchetypeArtifactId=archetype-lambda -Dservice=s3 -Dregion=US_WEST_2 \ -DarchetypeVersion=
2.X.X
\ -DgroupId=com.example.myapp \ -DartifactId=myapp
Note
Replace com.example.myapp with the full package namespace of your application. Also replace myapp with your project name. This becomes the name of the directory for your project.
To use the latest version of the archetype, replace 2.X.X
with the latest from Maven central
This command creates a Maven project using the archetype templating toolkit. The
archetype generates the scaffolding for an Amazon Lambda function handler project . This project
archetype is preconfigured to compile with Java SE 8 and includes a dependency to the version
of the SDK for Java 2.x specified with -DarchetypeVersion
.
For more information about creating and configuring Maven projects, see the Maven Getting Started Guide
Configure the Java compiler for Maven
If you created your project using the Amazon Lambda project archetype as described previously, the configuration of the Java compiler is already done for you.
To verify that this configuration is present, start by opening the pom.xml
file from the project folder you created (for example, myapp
) when you executed the previous command. Look on lines 11 and 12 to see the Java compiler version setting for this Maven project, and the required inclusion of the Maven compiler plugin on lines 71-75.
<project> <properties> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> </properties> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>${maven.compiler.plugin.version}</version> </plugin> </plugins> </build> </project>
If you create your project with a different archetype or by using another method, you must ensure that the Maven compiler plugin is part of the build and that its source and target properties are both set to 1.8 in the pom.xml
file.
See the previous snippet for one way to configure these required settings.
Alternatively, you can configure the compiler configuration inline with the plugin declaration, as follows.
<project> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> </plugins> </build> </project>
Declare the SDK as a dependency
To use the Amazon SDK for Java in your project, you need to declare it as a dependency in your project’s pom.xml
file.
If you created your project using the project archetype as described previously, the latest version of the SDK is already configured as a dependency in your project.
The archetype generates a BOM (bill of materials) artifact dependency for the
software.amazon.awssdk
group id. With a BOM, you do not have to specify the
maven version for individual artifact dependencies that share the same group id.
If you created your Maven project in a different way, configure the latest version of the SDK for your project by ensuring that the pom.xml
file contains the following.
<project> <properties> <aws.java.sdk.version>
2.X.X
</aws.java.sdk.version> </properties> <dependencyManagement> <dependencies> <dependency> <groupId>software.amazon.awssdk</groupId> <artifactId>bom</artifactId> <version>${aws.java.sdk.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> </project>
Note
Replace 2.X.X
in the pom.xml
file with the
latest
version of the Amazon SDK for Java 2.x
Set dependencies for SDK modules
Now that you have configured the SDK, you can add dependencies for one or more of the Amazon SDK for Java modules to use in your project.
Although you can specify the version number for each component, you don’t need to
because you already declared the SDK version in the dependencyManagement
section
using the bill of materials artifact. To load a different version of a given module, specify a
version number for its dependency.
If you created your project using the project archetype as described previously, your project is already configured with multiple dependencies. These include dependences for Amazon Lambda function handlers and Amazon S3, as follows.
<project> <dependencies> <dependency> <groupId>software.amazon.awssdk</groupId> <artifactId>s3</artifactId> <exclusions> <exclusion> <groupId>software.amazon.awssdk</groupId> <artifactId>netty-nio-client</artifactId> </exclusion> <exclusion> <groupId>software.amazon.awssdk</groupId> <artifactId>apache-client</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>software.amazon.awssdk</groupId> <artifactId>url-connection-client</artifactId> </dependency> <dependency> <groupId>com.amazonaws</groupId> <artifactId>aws-lambda-java-core</artifactId> <version>${aws.lambda.java.version}</version> </dependency> </dependencies> </project>
Note
In the pom.xml
example above, the dependencies are from different
groupId
s. The s3
dependency is from
software.amazon.awssdk
, whereas the aws-lambda-java-core
dependency is from com.amazonaws
. The BOM dependency management configuration
affects artifacts for software.amazon.awssdk
, so a version is needed for the
aws-lambda-java-core
artifact.
For the development of Lambda function handlers using
the SDK for Java 2.x, aws-lambda-java-core
is the correct dependency. However, if your
application needs to manage Lambda resources, using operations such as
listFunctions
, deleteFunction
, invokeFunction
, and
createFunction
, your application requires the following dependency.
<groupId>software.amazon.awssdk</groupId> <artifactId>lambda</artifactId>
Note
The s3
dependency excludes the the netty-nio-client
and
apache-client
transitive dependencies. In place of either of those HTTP
clients, the archetype includes the url-connection-client
dependency, which
helps reduce the startup latency for Amazon Lambda
functions.
Add the modules to your project for the Amazon Web Services service and features you need
for your project. The modules (dependencies) that are managed by the Amazon SDK for Java
BOM are listed on the Maven central
repository
Note
You can look at the pom.xml
file from a code example to determine which
dependencies you need for your project. For example, if you’re interested in the
dependencies for the DynamoDB service, see this examplepom.xml
file under /javav2/example_code/dynamodb
Build the entire SDK into your project
To optimize your application, we strongly recommend that you pull in only the components you need instead of the entire SDK. However, to build the entire Amazon SDK for Java into your project, declare it in your pom.xml
file, as follows.
<project> <dependencies> <dependency> <groupId>software.amazon.awssdk</groupId> <artifactId>aws-sdk-java</artifactId> <version>
2.X.X
</version> </dependency> </dependencies> </project>
Build your project
After you configure the pom.xml
file, you can use Maven to build your project.
To build your Maven project from the command line, open a terminal or command prompt window, navigate to your project directory (for example, myapp
), enter or paste the following command, then press Enter or Return.
mvn package
This creates a single .jar
file (JAR) in the target
directory (for example, myapp/target
). This JAR contains all of the SDK modules you specified as dependencies in your pom.xml
file.