AWS STS examples using SDK for Java 2.x

The following code examples show you how to perform actions and implement common scenarios by using the AWS SDK for Java 2.x with AWS STS.

Actions are code excerpts from larger programs and must be run in context. While actions show you how to call individual service functions, you can see actions in context in their related scenarios and cross-service examples.

Scenarios are code examples that show you how to accomplish a specific task by calling multiple functions within the same service.

Each example includes a link to GitHub, where you can find instructions on how to set up and run the code in context.

Actions

AssumeRole

The following code example shows how to use AssumeRole.

SDK for Java 2.x

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.sts.StsClient;
import software.amazon.awssdk.services.sts.model.AssumeRoleRequest;
import software.amazon.awssdk.services.sts.model.StsException;
import software.amazon.awssdk.services.sts.model.AssumeRoleResponse;
import software.amazon.awssdk.services.sts.model.Credentials;
import java.time.Instant;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.time.format.FormatStyle;
import java.util.Locale;

/**
 * To make this code example work, create a Role that you want to assume.
 * Then define a Trust Relationship in the AWS Console. You can use this as an
 * example:
 *
 * {
 * "Version": "2012-10-17",
 * "Statement": [
 * {
 * "Effect": "Allow",
 * "Principal": {
 * "AWS": "<Specify the ARN of your IAM user you are using in this code
 * example>"
 * },
 * "Action": "sts:AssumeRole"
 * }
 * ]
 * }
 *
 * For more information, see "Editing the Trust Relationship for an Existing
 * Role" in the AWS Directory Service guide.
 *
 * Also, set up your development environment, including your credentials.
 *
 * For information, see this documentation topic:
 *
 * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 */
public class AssumeRole {
    public static void main(String[] args) {
        final String usage = """

                Usage:
                    <roleArn> <roleSessionName>\s

                Where:
                    roleArn - The Amazon Resource Name (ARN) of the role to assume (for example, rn:aws:iam::000008047983:role/s3role).\s
                    roleSessionName - An identifier for the assumed role session (for example, mysession).\s
                """;

        if (args.length != 2) {
            System.out.println(usage);
            System.exit(1);
        }

        String roleArn = args[0];
        String roleSessionName = args[1];
        Region region = Region.US_EAST_1;
        StsClient stsClient = StsClient.builder()
                .region(region)
                .build();

        assumeGivenRole(stsClient, roleArn, roleSessionName);
        stsClient.close();
    }

    public static void assumeGivenRole(StsClient stsClient, String roleArn, String roleSessionName) {
        try {
            AssumeRoleRequest roleRequest = AssumeRoleRequest.builder()
                    .roleArn(roleArn)
                    .roleSessionName(roleSessionName)
                    .build();

            AssumeRoleResponse roleResponse = stsClient.assumeRole(roleRequest);
            Credentials myCreds = roleResponse.credentials();

            // Display the time when the temp creds expire.
            Instant exTime = myCreds.expiration();
            String tokenInfo = myCreds.sessionToken();

            // Convert the Instant to readable date.
            DateTimeFormatter formatter = DateTimeFormatter.ofLocalizedDateTime(FormatStyle.SHORT)
                    .withLocale(Locale.US)
                    .withZone(ZoneId.systemDefault());

            formatter.format(exTime);
            System.out.println("The token " + tokenInfo + "  expires on " + exTime);

        } catch (StsException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
}

• For API details, see AssumeRole in AWS SDK for Java 2.x API Reference.