Amazon Web Services 文档中描述的 Amazon Web Services 服务或功能可能因区域而异。要查看适用于中国区域的差异，请参阅 中国的 Amazon Web Services 服务入门 (PDF)。

我们宣布了即将推出 end-of-support 的 Amazon SDK for Java (v1)。建议您迁移到 Amazon SDK for Java v2。有关日期、其他详细信息以及如何迁移的信息，请参阅链接的公告。

本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

使用 CloudWatch 警报

创建警报

要根据 CloudWatch 指标创建警报，请使用已填充警报条件的 PutMetricAlarmRequest 调用 AmazonCloudWatchClient 的 putMetricAlarm 方法。

导入

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;

代码

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);

列出警报

要列出您已创建的 CloudWatch 警报，请使用您可用来设置结果选项的 DescribeAlarmsRequest 调用 AmazonCloudWatchClient 的 describeAlarms 方法。

导入

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;

代码

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;
    }
}

警报列表可以通过在 describeAlarms 返回的 DescribeAlarmsResult 中调用 getMetricAlarms 获得。

结果可以分页。要检索下一批结果，请在原始请求对象中使用 DescribeAlarmsResult 对象的 getNextToken 方法的返回值调用 setNextToken，并将已修改的请求对象传回对 describeAlarms 的另一个调用。

删除警报

要删除 CloudWatch 警报，请使用 DeleteAlarmsRequest（包含您要删除的一个或更多警报名称）调用 AmazonCloudWatchClient 的 deleteAlarms 方法。

导入

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;

代码

final AmazonCloudWatch cw =
    AmazonCloudWatchClientBuilder.defaultClient();

DeleteAlarmsRequest request = new DeleteAlarmsRequest()
    .withAlarmNames(alarm_name);

DeleteAlarmsResult response = cw.deleteAlarms(request);

更多信息