使用java api获取ec2中可用实例的数量

import com.amazonaws.auth.AWSStaticCredentialsProvider;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.ec2.AmazonEC2;
import com.amazonaws.services.ec2.AmazonEC2ClientBuilder;
import com.amazonaws.services.ec2.model.DescribeInstancesRequest;
import com.amazonaws.services.ec2.model.DescribeInstancesResult;
import com.amazonaws.services.ec2.model.Filter;
import com.amazonaws.services.ec2.model.Instance;
import com.amazonaws.services.ec2.model.Reservation;

public class EC2InstanceCount {
    public static void main(String[] args) {
        // 设置AWS凭证
        BasicAWSCredentials credentials = new BasicAWSCredentials("ACCESS_KEY", "SECRET_KEY");

        // 创建EC2客户端
        AmazonEC2 ec2Client = AmazonEC2ClientBuilder.standard()
                .withCredentials(new AWSStaticCredentialsProvider(credentials))
                .withRegion(Regions.US_EAST_1)
                .build();

        // 创建过滤器，仅获取运行中的实例
        Filter filter = new Filter("instance-state-name").withValues("running");

        // 创建描述实例请求
        DescribeInstancesRequest request = new DescribeInstancesRequest().withFilters(filter);

        // 发送请求并获取结果
        DescribeInstancesResult result = ec2Client.describeInstances(request);

        // 统计实例数量
        int instanceCount = 0;
        for (Reservation reservation : result.getReservations()) {
            for (Instance instance : reservation.getInstances()) {
                instanceCount++;
            }
        }

        System.out.println("可用实例数量：" + instanceCount);
    }
}