Skip to main content

Lambda Handler

(example)​

Create Handler​

There are three ways of creating a handler:

  • Creating a custom MethodHandler
  • Implementing the RequestHandler interface
  • Implementing the RequestStreamHandler interface

Custom MethodHandler​

public class LambdaMethodHandler {
    public String handleRequest(String input, Context context) {
        context.getLogger().log("Input: " + input);
        return "Hello World - " + input;
    }
}

RequestHandler Interface​

public class LambdaRequestHandler
  implements RequestHandler<String, String> {
    public String handleRequest(String input, Context context) {
        context.getLogger().log("Input: " + input);
        return "Hello World - " + input;
    }
}

RequestStreamHandler Interface​

public class LambdaRequestStreamHandler
  implements RequestStreamHandler {
    public void handleRequest(InputStream inputStream,
      OutputStream outputStream, Context context) {
        String input = IOUtils.toString(inputStream, "UTF-8");
        outputStream.write(("Hello World - " + input).getBytes());
    }
}

Deployment File​

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>zjc.examples</groupId>
    <artifactId>lambda-hello-world</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>21</maven.compiler.source>
        <maven.compiler.target>21</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com.amazonaws</groupId>
            <artifactId>aws-lambda-java-core</artifactId>
            <version>1.2.0</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.2.1</version>
                <configuration>
                    <createDependencyReducedPom>false</createDependencyReducedPom>
                </configuration>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

Build Deployment File​

mvn clean package