使用JMX监控TOMCAT
一、激活Tomcat的JMX远程配置
要通过JMX远程监控Tomcat，首先需要激活Tomcat的JMX远程配置。
① 先修改Tomcat的启动脚本，windows下为bin/catalina.bat（linux下为catalina.sh），添加以下内容，8999是jmxremote使用的端口号，第二个false表示不需要鉴权：
1 set JMX_REMOTE_CONFIG=-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=8999 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false 2 set CATALINA_OPTS=%CATALINA_OPTS% %JMX_REMOTE_CONFIG%
要注意以上语句的位置不能太后面，可以加在【if "%OS%" == "Windows_NT" setlocal】一句后的大段的注释后面。
参考官方说明：
http://tomcat.apache.org/tomcat-6.0-doc/monitoring.html#Enabling_JMX_Remote
② 上面的配置是不需要鉴权的，如果需要鉴权则添加的内容为：
1 set JMX_REMOTE_CONFIG=-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=8999 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=true -Dcom.sun.management.jmxremote.password.file=../conf/jmxremote.password -Dcom.sun.management.jmxremote.access.file=../conf/jmxremote.access 2 set CATALINA_OPTS=%CATALINA_OPTS% %JMX_REMOTE_CONFIG%
③ 然后复制并修改授权文件
$JAVA_HOME/jre/lib/management下有jmxremote.access和jmxremote.password的模板文件，将两个文件复制到$CATALINA_BASE/conf目录下
◆ 修改$CATALINA_BASE/conf/jmxremote.access 添加内容：
monitorRole readonly
controlRole readwrite
◆ 修改$CATALINA_BASE/conf/jmxremote.password 添加内容：
monitorRole chenfeng
controlRole chenfeng
注意： 如果进行了以上步骤导致Tomcat启动不了，那么很可能是密码文件的权限问题
需要修改jmxremote.password文件的访问权限，只有运行Tomcat的用户才能拥有访问权限 ：
Windows的NTFS文件系统下，选中文件，点右键 -->“属性”-->“安全”--> 点“高级”--> 点“更改权限”--> 去掉“从父项继承....”--> 弹出窗口中选“删除”，这样就删除了所有访问权限。再选“添加”--> “高级”--> “立即查找”，选中你的用户（或用户组，如果选用户不行那就选用户组），例administrator，点“确定"，“确定"。来到权限项目窗口，勾选“完全控制”，点“确定”，OK了。
官方的提示：
The password file should be read-only and only accessible by the operating system user Tomcat is running as.
④ 重新启动Tomcat，在Windows命令行输入“netstat -a”查看配置的端口号是否已打开，如果打开，说明上面的配置成功了。
⑤ 使用jconsole测试JMX。
运行$JAVA_HOME/bin目录下的jconsole.exe，打开J2SE监视和管理控制台，然后建立连接，如果是本地的Tomcat则直接选择然后点击连接，如果是远程的，则进入远程选项卡，填写地址、端口号、用户名、口令即可连接。。Mbean属性页中给出了相应的数据，Catalina中是tomcat的，java.lang是jvm的。对于加粗的黑体属性值，需双击一下才可看内容。
二、使用JMX监控Tomcat示例代码
1 String jmxURL = "service:jmx:rmi:///jndi/rmi://192.168.10.93:8999/jmxrmi"; 2 JMXServiceURL serviceURL = new JMXServiceURL(jmxURL); 3 4 Map map = new HashMap(); 5 // 用户名密码，在jmxremote.password文件中查看 6 String[] credentials = new String[] { "monitorRole", "tomcat" }; 7 map.put("jmx.remote.credentials", credentials); 8 JMXConnector connector = JMXConnectorFactory.connect(serviceURL, map); 9 MBeanServerConnection mbsc = connector.getMBeanServerConnection(); 10 11 // 端口最好是动态取得 12 ObjectName threadObjName = new ObjectName("Catalina:type=ThreadPool,name=http-8080"); 13 MBeanInfo mbInfo = mbsc.getMBeanInfo(threadObjName); 14 15 // tomcat的线程数对应的属性值 16 String attrName = "currentThreadCount"; 17 MBeanAttributeInfo[] mbAttributes = mbInfo.getAttributes(); 18 System.out.println("currentThreadCount:" + mbsc.getAttribute(threadObjName, attrName));
三、完整的示例代码文件
1 import java.lang.management.MemoryUsage; 2 import java.text.SimpleDateFormat; 3 import java.util.Date; 4 import java.util.Formatter; 5 import java.util.HashMap; 6 import java.util.Iterator; 7 import java.util.Map; 8 import java.util.Set; 9 10 import javax.management.MBeanAttributeInfo; 11 import javax.management.MBeanInfo; 12 import javax.management.MBeanServerConnection; 13 import javax.management.ObjectInstance; 14 import javax.management.ObjectName; 15 import javax.management.openmbean.CompositeDataSupport; 16 import javax.management.remote.JMXConnector; 17 import javax.management.remote.JMXConnectorFactory; 18 import javax.management.remote.JMXServiceURL; 19 20 public class JMXTest { 21 22 /** 23 * @param args 24 */ 25 public static void main(String[] args) { 26 try { 27 28 String jmxURL = "service:jmx:rmi:///jndi/rmi://127.0.0.1:8999/jmxrmi"; 29 30 JMXServiceURL serviceURL = new JMXServiceURL(jmxURL); 31 32 Map map = new HashMap(); 33 String[] credentials = new String[] { "monitorRole", "tomcat" }; 34 map.put("jmx.remote.credentials", credentials); 35 JMXConnector connector = JMXConnectorFactory.connect(serviceURL, 36 map); 37 MBeanServerConnection mbsc = connector.getMBeanServerConnection(); 38 39 // 端口最好是动态取得 40 ObjectName threadObjName = new ObjectName( 41 "Catalina:type=ThreadPool,name=http-8080"); 42 MBeanInfo mbInfo = mbsc.getMBeanInfo(threadObjName); 43 44 String attrName = "currentThreadCount";// tomcat的线程数对应的属性值 45 MBeanAttributeInfo[] mbAttributes = mbInfo.getAttributes(); 46 System.out.println("currentThreadCount:" 47 + mbsc.getAttribute(threadObjName, attrName)); 48 49 // heap 50 for (int j = 0; j < mbsc.getDomains().length; j++) { 51 System.out.println("###########" + mbsc.getDomains()[j]); 52 } 53 Set MBeanset = mbsc.queryMBeans(null, null); 54 System.out.println("MBeanset.size() : " + MBeanset.size()); 55 Iterator MBeansetIterator = MBeanset.iterator(); 56 while (MBeansetIterator.hasNext()) { 57 ObjectInstance objectInstance = (ObjectInstance) MBeansetIterator 58 .next(); 59 ObjectName objectName = objectInstance.getObjectName(); 60 String canonicalName = objectName.getCanonicalName(); 61 System.out.println("canonicalName : " + canonicalName); 62 if (canonicalName 63 .equals("Catalina:host=localhost,type=Cluster")) { 64 // Get details of cluster MBeans 65 System.out.println("Cluster MBeans Details:"); 66 System.out 67 .println("========================================="); 68 // getMBeansDetails(canonicalName); 69 String canonicalKeyPropList = objectName 70 .getCanonicalKeyPropertyListString(); 71 } 72 } 73 // ------------------------- system ---------------------- 74 ObjectName runtimeObjName = new ObjectName("java.lang:type=Runtime"); 75 System.out.println("厂商:" 76 + (String) mbsc.getAttribute(runtimeObjName, "VmVendor")); 77 System.out.println("程序:" 78 + (String) mbsc.getAttribute(runtimeObjName, "VmName")); 79 System.out.println("版本:" 80 + (String) mbsc.getAttribute(runtimeObjName, "VmVersion")); 81 Date starttime = new Date((Long) mbsc.getAttribute(runtimeObjName, 82 "StartTime")); 83 SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 84 System.out.println("启动时间:" + df.format(starttime)); 85 86 Long timespan = (Long) mbsc.getAttribute(runtimeObjName, "Uptime"); 87 System.out.println("连续工作时间:" + JMXTest.formatTimeSpan(timespan)); 88 // ------------------------ JVM ------------------------- 89 // 堆使用率 90 ObjectName heapObjName = new ObjectName("java.lang:type=Memory"); 91 MemoryUsage heapMemoryUsage = MemoryUsage 92 .from((CompositeDataSupport) mbsc.getAttribute(heapObjName, 93 "HeapMemoryUsage")); 94 long maxMemory = heapMemoryUsage.getMax();// 堆最大 95 long commitMemory = heapMemoryUsage.getCommitted();// 堆当前分配 96 long usedMemory = heapMemoryUsage.getUsed(); 97 System.out.println("heap:" + (double) usedMemory * 100 98 / commitMemory + "%");// 堆使用率 99 100 MemoryUsage nonheapMemoryUsage = MemoryUsage 101 .from((CompositeDataSupport) mbsc.getAttribute(heapObjName, 102 "NonHeapMemoryUsage")); 103 long noncommitMemory = nonheapMemoryUsage.getCommitted(); 104 long nonusedMemory = heapMemoryUsage.getUsed(); 105 System.out.println("nonheap:" + (double) nonusedMemory * 100 106 / noncommitMemory + "%"); 107 108 ObjectName permObjName = new ObjectName( 109 "java.lang:type=MemoryPool,name=Perm Gen"); 110 MemoryUsage permGenUsage = MemoryUsage 111 .from((CompositeDataSupport) mbsc.getAttribute(permObjName, 112 "Usage")); 113 long committed = permGenUsage.getCommitted();// 持久堆大小 114 long used = heapMemoryUsage.getUsed();// 115 System.out.println("perm gen:" + (double) used * 100 / committed 116 + "%");// 持久堆使用率 117 118 // -------------------- Session --------------- 119 ObjectName managerObjName = new ObjectName( 120 "Catalina:type=Manager,*"); 121 Set<ObjectName> s = mbsc.queryNames(managerObjName, null); 122 for (ObjectName obj : s) { 123 System.out.println("应用名:" + obj.getKeyProperty("path")); 124 ObjectName objname = new ObjectName(obj.getCanonicalName()); 125 System.out.println("最大会话数:" 126 + mbsc.getAttribute(objname, "maxActiveSessions")); 127 System.out.println("会话数:" 128 + mbsc.getAttribute(objname, "activeSessions")); 129 System.out.println("活动会话数:" 130 + mbsc.getAttribute(objname, "sessionCounter")); 131 } 132 133 // ----------------- Thread Pool ---------------- 134 ObjectName threadpoolObjName = new ObjectName( 135 "Catalina:type=ThreadPool,*"); 136 Set<ObjectName> s2 = mbsc.queryNames(threadpoolObjName, null); 137 for (ObjectName obj : s2) { 138 System.out.println("端口名:" + obj.getKeyProperty("name")); 139 ObjectName objname = new ObjectName(obj.getCanonicalName()); 140 System.out.println("最大线程数:" 141 + mbsc.getAttribute(objname, "maxThreads")); 142 System.out.println("当前线程数:" 143 + mbsc.getAttribute(objname, "currentThreadCount")); 144 System.out.println("繁忙线程数:" 145 + mbsc.getAttribute(objname, "currentThreadsBusy")); 146 } 147 148 } catch (Exception e) { 149 e.printStackTrace(); 150 } 151 } 152 153 public static String formatTimeSpan(long span) { 154 long minseconds = span % 1000; 155 156 span = span / 1000; 157 long seconds = span % 60; 158 159 span = span / 60; 160 long mins = span % 60; 161 162 span = span / 60; 163 long hours = span % 24; 164 165 span = span / 24; 166 long days = span; 167 return (new Formatter()).format("%1$d天 %2$02d:%3$02d:%4$02d.%5$03d", 168 days, hours, mins, seconds, minseconds).toString(); 169 } 170 }
