Hikari是SpringBoot 2.0中默认的连接池。
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。示例代码如下，采用SpringBoot集成，定时采集连接池连接状态。@Component@Controller@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)@EnableSchedulingpublic class HikariTest { private static HikariPoolMXBean poolProxy; private static final Logger log = LoggerFactory.getLogger(HikariTest.class); 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("db10$ZTE"); hikaridatasource.setDriverClassName("com.mysql.cj.jdbc.Driver"); hikaridatasource.setRegisterMbeans(true); hikaridatasource.setPoolName("HikariConnectionPool"); MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer(); ObjectName poolName = new ObjectName("com.zaxxer.hikari:type=Pool (" + hikaridatasource.getPoolName() + ")"); poolProxy = JMX.newMXBeanProxy(mBeanServer, poolName, HikariPoolMXBean.class); Connection conn = hikaridatasource.getConnection(); Statement sm = conn.createStatement(); ResultSet rs = null; for (int i = 0; i < 999999999; i++) { rs = sm.executeQuery("select name from test.t1"); } rs.close(); sm.close(); conn.close(); hikaridatasource.close(); } @Scheduled(fixedRate = 1000) public void HikariMonitor() { if(poolProxy == null) { log.info("Hikari not initialized,please wait..."); }else { log.info("HikariPoolState = " + "Active=[" + String.valueOf(poolProxy.getActiveConnections() + "] " + "Idle=[" + String.valueOf(poolProxy.getIdleConnections() + "] " + "Wait=["+poolProxy.getThreadsAwaitingConnection()+"] " + "Total=["+poolProxy.getTotalConnections()+"]"))); } }复制代码 另，在github上，有几位小伙伴都提出了同样的issue（我也遇到了），在
ObjectName poolName = new ObjectName("com.zaxxer.hikari:type=Pool (" + hikaridatasource.getPoolName() + ")");复制代码 可能会抛错
22:06:23.231 [main] DEBUG com.zaxxer.hikari.HikariConfig - Driver class com.mysql.cj.jdbc.Driver found in Thread context class loader sun.misc.Launcher$AppClassLoader@73d16e93Exception 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复制代码
这里提醒小伙伴，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);复制代码
代码效果如下所示
2019-03-09 02:05:03.725 INFO com.zte.hikariTest.HikariTest.67 -Hikari connection pool is not already...please wait...2019-03-09 02:05:03.726 INFO o.a.c.http11.Http11NioProtocol.173 -Starting ProtocolHandler ["http-nio-8080"]2019-03-09 02:05:03.760 INFO o.s.b.w.e.t.TomcatWebServer.204 -Tomcat started on port(s): 8080 (http) with context path ''2019-03-09 02:05:03.763 INFO com.zte.hikariTest.HikariTest.59 -Started HikariTest in 3.487 seconds (JVM running for 3.98)2019-03-09 02:05:03.775 INFO c.z.hikari.HikariDataSource.110 -HikariConnectionPool - Starting...2019-03-09 02:05:04.439 INFO c.z.hikari.HikariDataSource.123 -HikariConnectionPool - Start completed.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]复制代码