使用 MBean 和 日志查看 Tomcat 线程池核心属性数据

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CustomTomcatThreadPoolMBean

com.qww.config;public interface CustomTomcatThreadPoolMBean {String getStatus();
}

CustomTomcatThreadPool

package com.qww.config;import com.alibaba.fastjson.JSON;
import org.apache.tomcat.util.threads.ThreadPoolExecutor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.web.context.WebServerApplicationContext;
import org.springframework.boot.web.embedded.tomcat.TomcatWebServer;
import org.springframework.stereotype.Service;import javax.annotation.PostConstruct;
import javax.management.InstanceAlreadyExistsException;
import javax.management.MBeanRegistrationException;
import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.NotCompliantMBeanException;
import javax.management.ObjectName;
import java.lang.management.ManagementFactory;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;@Service
public class CustomTomcatThreadPool implements CustomTomcatThreadPoolMBean {private final static Logger logger = LoggerFactory.getLogger(CustomTomcatThreadPool.class);@AutowiredWebServerApplicationContext webServerApplicationContext;@Overridepublic String getStatus() {return buildStatus();}private String buildStatus() {logger.info("==>>: webServerApplicationContext:{} ", webServerApplicationContext);ThreadPoolExecutor executor = (ThreadPoolExecutor) ((TomcatWebServer) webServerApplicationContext.getWebServer()).getTomcat().getConnector().getProtocolHandler().getExecutor();logger.info("==>>: 这行日志如果没有输出，就是上一行代码报错了。虽然报错，但由于当前线程[RMP TCP Connection(x)-ip]的特殊性，并不会在控制台打印堆栈");Map<String, String> returnMap = new LinkedHashMap<>();returnMap.put("核心线程数(corePoolSize)", String.valueOf(executor.getCorePoolSize()));returnMap.put("最大线程数(maximumPoolSize)", String.valueOf(executor.getMaximumPoolSize()));returnMap.put("活跃线程数(activeCount)", String.valueOf(executor.getActiveCount()));returnMap.put("池中当前线程数(poolSize)", String.valueOf(executor.getPoolSize()));returnMap.put("历史最大线程数(largestPoolSize)", String.valueOf(executor.getLargestPoolSize()));returnMap.put("工作队列任务数量(workQueue.size)", String.valueOf(executor.getQueue().size()));returnMap.put("线程允许空闲时间/s(keepAliveTime)", String.valueOf(executor.getKeepAliveTime(TimeUnit.SECONDS)));returnMap.put("核心线程数是否允许被回收(allowCoreThreadTimeOut)", String.valueOf(executor.allowsCoreThreadTimeOut()));returnMap.put("提交任务总数(submittedCount)", String.valueOf(executor.getSubmittedCount()));returnMap.put("历史执行任务的总数(近似值)(taskCount)", String.valueOf(executor.getTaskCount()));returnMap.put("历史完成任务的总数(近似值)(completedTaskCount)", String.valueOf(executor.getCompletedTaskCount()));returnMap.put("拒绝策略(ejectedExecutionHandler.class)", executor.getRejectedExecutionHandler().getClass().getCanonicalName());String res = JSON.toJSONString(returnMap);logger.info("==>>: {}", res);return res;}@PostConstructpublic void post() {MBeanServer server = ManagementFactory.getPlatformMBeanServer();ObjectName objectName = null;try {objectName = new ObjectName("qww:type=CustomTomcatThreadPool");} catch (MalformedObjectNameException e) {e.printStackTrace();}try {// 这里的key 必须使用Spring 中注册的对象，也就是当前对象server.registerMBean(this, objectName);} catch (InstanceAlreadyExistsException | MBeanRegistrationException | NotCompliantMBeanException e) {e.printStackTrace();}}}