The AWS SDK for Java 1.x reached end-of-support on December 31, 2025. We recommend that you migrate to the [AWS SDK for Java 2.x](https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/home.html) to continue receiving new features, availability improvements, and security updates. # CloudWatch Examples Using the AWS SDK for Java This section provides examples of programming [CloudWatch](https://aws.amazon.com/cloudwatch/) using the [AWS SDK for Java](https://aws.amazon.com/sdk-for-java/). Amazon CloudWatch monitors your Amazon Web Services (AWS) resources and the applications you run on AWS in real time. You can use CloudWatch to collect and track metrics, which are variables you can measure for your resources and applications. CloudWatch alarms send notifications or automatically make changes to the resources you are monitoring based on rules that you define. For more information about CloudWatch, see the [Amazon CloudWatch User Guide](http://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/). **Note** The examples include only the code needed to demonstrate each technique. The [complete example code is available on GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/master/java). From there, you can download a single source file or clone the repository locally to get all the examples to build and run. **Topics** + [Getting Metrics from CloudWatch](examples-cloudwatch-get-metrics.md) + [Publishing Custom Metric Data](examples-cloudwatch-publish-custom-metrics.md) + [Working with CloudWatch Alarms](examples-cloudwatch-create-alarms.md) + [Using Alarm Actions in CloudWatch](examples-cloudwatch-use-alarm-actions.md) + [Sending Events to CloudWatch](examples-cloudwatch-send-events.md) # Getting Metrics from CloudWatch ## Listing Metrics To list CloudWatch metrics, create a [ListMetricsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/ListMetricsRequest.html) and call the AmazonCloudWatchClient’s `listMetrics` method. You can use the `ListMetricsRequest` to filter the returned metrics by namespace, metric name, or dimensions. **Note** A list of metrics and dimensions that are posted by AWS services can be found within the \$1https---docs-aws-amazon-com-AmazonCloudWatch-latest-monitoring-CW-Support-For-AWS-html\$1[Amazon CloudWatch Metrics and Dimensions Reference] in the Amazon CloudWatch User Guide. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.ListMetricsRequest; import com.amazonaws.services.cloudwatch.model.ListMetricsResult; import com.amazonaws.services.cloudwatch.model.Metric; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); ListMetricsRequest request = new ListMetricsRequest() .withMetricName(name) .withNamespace(namespace); boolean done = false; while(!done) { ListMetricsResult response = cw.listMetrics(request); for(Metric metric : response.getMetrics()) { System.out.printf( "Retrieved metric %s", metric.getMetricName()); } request.setNextToken(response.getNextToken()); if(response.getNextToken() == null) { done = true; } } ``` The metrics are returned in a [ListMetricsResult](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/ListMetricsResult.html) by calling its `getMetrics` method. The results may be *paged*. To retrieve the next batch of results, call `setNextToken` on the original request object with the return value of the `ListMetricsResult` object’s `getNextToken` method, and pass the modified request object back to another call to `listMetrics`. ## More Information + [ListMetrics](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_ListMetrics.html) in the Amazon CloudWatch API Reference. # Publishing Custom Metric Data A number of AWS services publish [their own metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/aws-namespaces.html) in namespaces beginning with " `AWS` " You can also publish custom metric data using your own namespace (as long as it doesn’t begin with " `AWS` "). ## Publish Custom Metric Data To publish your own metric data, call the AmazonCloudWatchClient’s `putMetricData` method with a [PutMetricDataRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/PutMetricDataRequest.html). The `PutMetricDataRequest` must include the custom namespace to use for the data, and information about the data point itself in a [MetricDatum](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/MetricDatum.html) object. **Note** You cannot specify a namespace that begins with " `AWS` ". Namespaces that begin with " `AWS` " are reserved for use by Amazon Web Services products. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.Dimension; import com.amazonaws.services.cloudwatch.model.MetricDatum; import com.amazonaws.services.cloudwatch.model.PutMetricDataRequest; import com.amazonaws.services.cloudwatch.model.PutMetricDataResult; import com.amazonaws.services.cloudwatch.model.StandardUnit; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); Dimension dimension = new Dimension() .withName("UNIQUE_PAGES") .withValue("URLS"); MetricDatum datum = new MetricDatum() .withMetricName("PAGES_VISITED") .withUnit(StandardUnit.None) .withValue(data_point) .withDimensions(dimension); PutMetricDataRequest request = new PutMetricDataRequest() .withNamespace("SITE/TRAFFIC") .withMetricData(datum); PutMetricDataResult response = cw.putMetricData(request); ``` ## More Information + [Using Amazon CloudWatch Metrics](http://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/working_with_metrics.html) in the Amazon CloudWatch User Guide. + [AWS Namespaces](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/aws-namespaces.html) in the Amazon CloudWatch User Guide. + [PutMetricData](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutMetricData.html) in the Amazon CloudWatch API Reference. # Working with CloudWatch Alarms ## Create an Alarm To create an alarm based on a CloudWatch metric, call the AmazonCloudWatchClient’s `putMetricAlarm` method with a [PutMetricAlarmRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/PutMetricAlarmRequest.html) filled with the alarm conditions. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.ComparisonOperator; import com.amazonaws.services.cloudwatch.model.Dimension; import com.amazonaws.services.cloudwatch.model.PutMetricAlarmRequest; import com.amazonaws.services.cloudwatch.model.PutMetricAlarmResult; import com.amazonaws.services.cloudwatch.model.StandardUnit; import com.amazonaws.services.cloudwatch.model.Statistic; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); Dimension dimension = new Dimension() .withName("InstanceId") .withValue(instanceId); PutMetricAlarmRequest request = new PutMetricAlarmRequest() .withAlarmName(alarmName) .withComparisonOperator( ComparisonOperator.GreaterThanThreshold) .withEvaluationPeriods(1) .withMetricName("CPUUtilization") .withNamespace("{AWS}/EC2") .withPeriod(60) .withStatistic(Statistic.Average) .withThreshold(70.0) .withActionsEnabled(false) .withAlarmDescription( "Alarm when server CPU utilization exceeds 70%") .withUnit(StandardUnit.Seconds) .withDimensions(dimension); PutMetricAlarmResult response = cw.putMetricAlarm(request); ``` ## List Alarms To list the CloudWatch alarms that you have created, call the AmazonCloudWatchClient’s `describeAlarms` method with a [DescribeAlarmsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/DescribeAlarmsRequest.html) that you can use to set options for the result. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.DescribeAlarmsRequest; import com.amazonaws.services.cloudwatch.model.DescribeAlarmsResult; import com.amazonaws.services.cloudwatch.model.MetricAlarm; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); boolean done = false; DescribeAlarmsRequest request = new DescribeAlarmsRequest(); while(!done) { DescribeAlarmsResult response = cw.describeAlarms(request); for(MetricAlarm alarm : response.getMetricAlarms()) { System.out.printf("Retrieved alarm %s", alarm.getAlarmName()); } request.setNextToken(response.getNextToken()); if(response.getNextToken() == null) { done = true; } } ``` The list of alarms can be obtained by calling `getMetricAlarms` on the [DescribeAlarmsResult](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/DescribeAlarmsResult.html) that is returned by `describeAlarms`. The results may be *paged*. To retrieve the next batch of results, call `setNextToken` on the original request object with the return value of the `DescribeAlarmsResult` object’s `getNextToken` method, and pass the modified request object back to another call to `describeAlarms`. **Note** You can also retrieve alarms for a specific metric by using the AmazonCloudWatchClient’s `describeAlarmsForMetric` method. Its use is similar to `describeAlarms`. ## Delete Alarms To delete CloudWatch alarms, call the AmazonCloudWatchClient’s `deleteAlarms` method with a [DeleteAlarmsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/DeleteAlarmsRequest.html) containing one or more names of alarms that you want to delete. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.DeleteAlarmsRequest; import com.amazonaws.services.cloudwatch.model.DeleteAlarmsResult; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); DeleteAlarmsRequest request = new DeleteAlarmsRequest() .withAlarmNames(alarm_name); DeleteAlarmsResult response = cw.deleteAlarms(request); ``` ## More Information + [Creating Amazon CloudWatch Alarms](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html) in the Amazon CloudWatch User Guide + [PutMetricAlarm](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutMetricAlarm.html) in the Amazon CloudWatch API Reference + [DescribeAlarms](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_DescribeAlarms.html) in the Amazon CloudWatch API Reference + [DeleteAlarms](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_DeleteAlarms.html) in the Amazon CloudWatch API Reference # Using Alarm Actions in CloudWatch Using CloudWatch alarm actions, you can create alarms that perform actions such as automatically stopping, terminating, rebooting, or recovering Amazon EC2 instances. **Note** Alarm actions can be added to an alarm by using the [PutMetricAlarmRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/PutMetricAlarmRequest.html)'s `setAlarmActions` method when [creating an alarm](examples-cloudwatch-create-alarms.md). ## Enable Alarm Actions To enable alarm actions for a CloudWatch alarm, call the AmazonCloudWatchClient’s `enableAlarmActions` with a [EnableAlarmActionsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/EnableAlarmActionsRequest.html) containing one or more names of alarms whose actions you want to enable. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.EnableAlarmActionsRequest; import com.amazonaws.services.cloudwatch.model.EnableAlarmActionsResult; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); EnableAlarmActionsRequest request = new EnableAlarmActionsRequest() .withAlarmNames(alarm); EnableAlarmActionsResult response = cw.enableAlarmActions(request); ``` ## Disable Alarm Actions To disable alarm actions for a CloudWatch alarm, call the AmazonCloudWatchClient’s `disableAlarmActions` with a [DisableAlarmActionsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatch/model/DisableAlarmActionsRequest.html) containing one or more names of alarms whose actions you want to disable. **Imports** ``` import com.amazonaws.services.cloudwatch.AmazonCloudWatch; import com.amazonaws.services.cloudwatch.AmazonCloudWatchClientBuilder; import com.amazonaws.services.cloudwatch.model.DisableAlarmActionsRequest; import com.amazonaws.services.cloudwatch.model.DisableAlarmActionsResult; ``` **Code** ``` final AmazonCloudWatch cw = AmazonCloudWatchClientBuilder.defaultClient(); DisableAlarmActionsRequest request = new DisableAlarmActionsRequest() .withAlarmNames(alarmName); DisableAlarmActionsResult response = cw.disableAlarmActions(request); ``` ## More Information + [Create Alarms to Stop, Terminate, Reboot, or Recover an Instance](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/UsingAlarmActions.html) in the Amazon CloudWatch User Guide + [PutMetricAlarm](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutMetricAlarm.html) in the Amazon CloudWatch API Reference + [EnableAlarmActions](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_EnableAlarmActions.html) in the Amazon CloudWatch API Reference + [DisableAlarmActions](http://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_DisableAlarmActions.html) in the Amazon CloudWatch API Reference # Sending Events to CloudWatch CloudWatch Events delivers a near real-time stream of system events that describe changes in AWS resources to Amazon EC2 instances, Lambda functions, Kinesis streams, Amazon ECS tasks, Step Functions state machines, Amazon SNS topics, Amazon SQS queues, or built-in targets. You can match events and route them to one or more target functions or streams by using simple rules. ## Add Events To add custom CloudWatch events, call the AmazonCloudWatchEventsClient’s `putEvents` method with a [PutEventsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatchevents/model/PutEventsRequest.html) object that contains one or more [PutEventsRequestEntry](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatchevents/model/PutEventsRequestEntry.html) objects that provide details about each event. You can specify several parameters for the entry such as the source and type of the event, resources associated with the event, and so on. **Note** You can specify a maximum of 10 events per call to `putEvents`. **Imports** ``` import com.amazonaws.services.cloudwatchevents.AmazonCloudWatchEvents; import com.amazonaws.services.cloudwatchevents.AmazonCloudWatchEventsClientBuilder; import com.amazonaws.services.cloudwatchevents.model.PutEventsRequest; import com.amazonaws.services.cloudwatchevents.model.PutEventsRequestEntry; import com.amazonaws.services.cloudwatchevents.model.PutEventsResult; ``` **Code** ``` final AmazonCloudWatchEvents cwe = AmazonCloudWatchEventsClientBuilder.defaultClient(); final String EVENT_DETAILS = "{ \"key1\": \"value1\", \"key2\": \"value2\" }"; PutEventsRequestEntry request_entry = new PutEventsRequestEntry() .withDetail(EVENT_DETAILS) .withDetailType("sampleSubmitted") .withResources(resource_arn) .withSource("aws-sdk-java-cloudwatch-example"); PutEventsRequest request = new PutEventsRequest() .withEntries(request_entry); PutEventsResult response = cwe.putEvents(request); ``` ## Add Rules To create or update a rule, call the AmazonCloudWatchEventsClient’s `putRule` method with a [PutRuleRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatchevents/model/PutRuleRequest.html) with the name of the rule and optional parameters such as the [event pattern](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/CloudWatchEventsandEventPatterns.html), IAM role to associate with the rule, and a [scheduling expression](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html) that describes how often the rule is run. **Imports** ``` import com.amazonaws.services.cloudwatchevents.AmazonCloudWatchEvents; import com.amazonaws.services.cloudwatchevents.AmazonCloudWatchEventsClientBuilder; import com.amazonaws.services.cloudwatchevents.model.PutRuleRequest; import com.amazonaws.services.cloudwatchevents.model.PutRuleResult; import com.amazonaws.services.cloudwatchevents.model.RuleState; ``` **Code** ``` final AmazonCloudWatchEvents cwe = AmazonCloudWatchEventsClientBuilder.defaultClient(); PutRuleRequest request = new PutRuleRequest() .withName(rule_name) .withRoleArn(role_arn) .withScheduleExpression("rate(5 minutes)") .withState(RuleState.ENABLED); PutRuleResult response = cwe.putRule(request); ``` ## Add Targets Targets are the resources that are invoked when a rule is triggered. Example targets include Amazon EC2 instances, Lambda functions, Kinesis streams, Amazon ECS tasks, Step Functions state machines, and built-in targets. To add a target to a rule, call the AmazonCloudWatchEventsClient’s `putTargets` method with a [PutTargetsRequest](https://docs.aws.amazon.com/sdk-for-java/v1/reference/com/amazonaws/services/cloudwatchevents/model/PutTargetsRequest.html) containing the rule to update and a list of targets to add to the rule. **Imports** ``` import com.amazonaws.services.cloudwatchevents.AmazonCloudWatchEvents; import com.amazonaws.services.cloudwatchevents.AmazonCloudWatchEventsClientBuilder; import com.amazonaws.services.cloudwatchevents.model.PutTargetsRequest; import com.amazonaws.services.cloudwatchevents.model.PutTargetsResult; import com.amazonaws.services.cloudwatchevents.model.Target; ``` **Code** ``` final AmazonCloudWatchEvents cwe = AmazonCloudWatchEventsClientBuilder.defaultClient(); Target target = new Target() .withArn(function_arn) .withId(target_id); PutTargetsRequest request = new PutTargetsRequest() .withTargets(target) .withRule(rule_name); PutTargetsResult response = cwe.putTargets(request); ``` ## More Information + [Adding Events with PutEvents](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/AddEventsPutEvents.html) in the Amazon CloudWatch Events User Guide + [Schedule Expressions for Rules](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html) in the Amazon CloudWatch Events User Guide + [Event Types for CloudWatch Events](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/EventTypes.html) in the Amazon CloudWatch Events User Guide + [Events and Event Patterns](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/CloudWatchEventsandEventPatterns.html) in the Amazon CloudWatch Events User Guide + [PutEvents](http://docs.aws.amazon.com/AmazonCloudWatchEvents/latest/APIReference/API_PutEvents.html) in the Amazon CloudWatch Events API Reference + [PutTargets](http://docs.aws.amazon.com/AmazonCloudWatchEvents/latest/APIReference/API_PutTargets.html) in the Amazon CloudWatch Events API Reference + [PutRule](http://docs.aws.amazon.com/AmazonCloudWatchEvents/latest/APIReference/API_PutRule.html) in the Amazon CloudWatch Events API Reference