如何实现Hikari连接池使用SpringBoot配置JMX监控

Hikari是Spring Boot默认的数据库连接池。区别于C3P0直接通过连接池对象获取各项状态指标，Hikari需要通过JMX来获取。Demo如下，采用Spring Boot集成，定时采集连接状态。

public static void main(String[] args) throws SQLException, MalformedObjectNameException, InterruptedException {

 SpringApplication.run(HikariTest.class, args);

 HikariDataSource hikaridatasource = new HikariDataSource();

 hikaridatasource.setJdbcUrl("jdbc:mysql://localhost:3306?serverTimezone=GMT");

 hikaridatasource.setUsername("root");

 hikaridatasource.setPassword("");

 hikaridatasource.setDriverClassName("com.mysql.cj.jdbc.Driver");

 hikaridatasource.setRegisterMbeans(true);

 hikaridatasource.setPoolName("HikariConnectionPool");

 MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();

 ObjectName poolName = new ObjectName("com.zaxxer.hikari:type=Pool (" + hikaridatasource.getPoolName() + ")");

 poolProxy = JMX.newMXBeanProxy(mBeanServer, poolName, HikariPoolMXBean.class);

 Connection conn = hikaridatasource.getConnection();

 Statement sm = conn.createStatement();

 ResultSet rs = null;

 for (int i = 0; i < 999999999; i++) {

  rs = sm.executeQuery("select name from test.t1");

 }

 rs.close();

 sm.close();

 conn.close();

 hikaridatasource.close();

}

@Scheduled(fixedRate = 1000)

public void HikariMonitor() {

 if(poolProxy == null) {

  log.info("Hikari not initialized,please wait...");

 }else {

  log.info("HikariPoolState = "

  + "Active=[" + String.valueOf(poolProxy.getActiveConnections() + "] "

  + "Idle=[" + String.valueOf(poolProxy.getIdleConnections() + "] "

  + "Wait=["+poolProxy.getThreadsAwaitingConnection()+"] "

  + "Total=["+poolProxy.getTotalConnections()+"]")));

 } 

}

另外，在github有提到这样的issue：

ObjectName poolName = new ObjectName("com.zaxxer.hikari:type=Pool (" + hikaridatasource.getPoolName() + ")");

可能会抛错

22:06:23.231 [main] DEBUG com.zaxxer.hikari.HikariConfig - Driver class com.mysql.cj.jdbc.Driver found in Thread context class loader sun.misc.Launcher$AppClassLoader@73d16e93

Exception in thread "main" java.lang.reflect.UndeclaredThrowableException

 at com.sun.proxy.$Proxy2.getIdleConnections(Unknown Source)

 at com.zte.hikariTest.HikariTest.main(HikariTest.java:32)

Caused by: javax.management.InstanceNotFoundException: com.zaxxer.hikari:type=Pool (foo)

 at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getMBean(Unknown Source)

 at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(Unknown Source)

 at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(Unknown Source)

 at com.sun.jmx.mbeanserver.MXBeanProxy$GetHandler.invoke(Unknown Source)

 at com.sun.jmx.mbeanserver.MXBeanProxy.invoke(Unknown Source)

 at javax.management.MBeanServerInvocationHandler.invoke(Unknown Source)

 ... 2 more

这是因为Hikari设置参数同样支持setHikariConfig和配置文件两种配置方式，请选择其中一种进行配置，而不是二者一起使用。并且请配置属性如下，否则 JMX 无法生效。

hikaridatasource.setRegisterMbeans(true);

代码效果如下所示

2019-03-09 02:05:04.738 INFO com.zte.hikariTest.HikariTest.69 -HikariPoolState = Active=[1] Idle=[9] Wait=[0] Total=[10]

2019-03-09 02:05:05.740 INFO com.zte.hikariTest.HikariTest.69 -HikariPoolState = Active=[1] Idle=[9] Wait=[0] Total=[10]

2019-03-09 02:05:06.732 INFO com.zte.hikariTest.HikariTest.69 -HikariPoolState = Active=[1] Idle=[9] Wait=[0] Total=[10]

2019-03-09 02:05:07.738 INFO com.zte.hikariTest.HikariTest.69 -HikariPoolState = Active=[1] Idle=[9] Wait=[0] Total=[10]