远程调用JMX开放的方法
JMX的功能主要通过远程调用RMI来实现。本文以获取c3po连接池连接数量为例(本文对c3po稍做了修改，以便监控)：具体实现如下
import java.util.HashMap;import java.util.Map;import javax.management.MBeanServerConnection;import javax.management.ObjectName;import javax.management.remote.JMXConnector;import javax.management.remote.JMXConnectorFactory;import javax.management.remote.JMXServiceURL;public class JmxService {private static final String C3P0_REGISTRY_OBJNAME ="com.mchange.v2.c3p0:type=C3P0Registry";private static final String C3P0_REGISTRY_OPERNAME ="getPooledDataSourcesIdentity";private String username = "controlRole";private String password = "123qwe";public void setUsername(String username) {this.username = username;}public void setPassword(String password) {this.password = password;}//sign 参数类型的说明public Object invokeMBeanMethod(String url,String operName,Object[] params,String[] signs) throws Exception{JMXConnector connector = null;try {JMXServiceURL serviceURL = new JMXServiceURL(url);if(username == null || username.length()==0){//不需要权限认证的连接器connector = JMXConnectorFactory.connect(serviceURL);}else{Map<String,Object> environment = new HashMap<String,Object>(); environment.put(JMXConnector.CREDENTIALS, new String[] {username,password}); connector = JMXConnectorFactory.connect(serviceURL,environment);}//得到MBean服务连接MBeanServerConnection connection =connector.getMBeanServerConnection();//调用JMX功能方法,得到返回值Object pdsId = connection.invoke(new ObjectName(C3P0_REGISTRY_OBJNAME), C3P0_REGISTRY_OPERNAME, new String[]{null}, new String[] {"java.lang.String"});String objName = "com.mchange.v2.c3p0:type=PooledDataSource["+pdsId+"]";Object res = connection.invoke(new ObjectName(objName), operName, params, signs);return res;} finally{if(connector!=null)connector.close();}}public static void main(String[] args)throws Exception {String url = "service:jmx:rmi:///jndi/rmi://192.168.6.3:9998/jmxrmi";String operName = "getMaxPoolSize";//String operName = "allIdentityTokens";Object[] params = null;String[] signs = null;JmxService jmxService = new JmxService();Object res = jmxService.invokeMBeanMethod(url,operName, params, signs);System.out.println(res);}}?执行结果：10