关于java:Hikari连接池使用SpringBoot配置JMX监控

Hikari 是 SpringBoot 2.0 中默认的连接池。
区别于 c3p0 间接通过连接池对象获取各项状态指标，Hikari 须要通过 JMX 来获取。
示例代码如下，采纳 SpringBoot 集成，定时采集连接池连贯状态。

@Component
@Controller
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableScheduling
public 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()+"]")));
        }
        
    }

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() + ")");

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

Hikari 设置参数同样反对 setHikariConfig 和配置文件两种配置形式，请抉择其中一种进行配置，而不是二者一起应用。并且请配置属性如下，否则 JMX 无奈失效。

hikaridatasource.setRegisterMbeans(true);

代码成果如下所示

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]