前言：做了一个监控应用服务器的项目（支持Tocmat、WebSphere、WebLogic各版本）， 过程也算是磕磕绊绊，由于网上缺少相关资料，或者深陷于知识的海洋难以寻觅到有效的资料，因而走过不少弯路，遇过不少困难。为了留下点印记，给后来人留下 点经验之谈，助之少走弯路，故将这些经验整理出来，与大家分享。水平有限，难免疏漏，还望指正。如有疑问，欢迎留言，或者加入Q群参与讨 论：35526521。
其实学习一项新的技术，刚开始最困难就是难以找到有效的资料，OK，首先分享几个官方文档的地址：
几个重要的官方文档地址
——相当于葵花宝典的功效（放心，不需自宫）
一、使用 JMX 开发自定义管理实用工具
http://www.oraclefmw.com/wls92/jmx/index.html
这是针对WebLogic 9.2的中文版，第一好东西，里面不仅讲解有原理讲解，还有Demo和教程
二、使用JMX访问WebLogic Server MBean的Demo和教程
● WebLogic 9.x：
http://download.oracle.com/docs/cd/E13222_01/wls/docs90/jmx/accessWLS.html
● WebLogic 10.x：
http://download.oracle.com/docs/cd/E11035_01/wls100/jmx/accessWLS.html
三、WebLogic的MBean参考手册
http://download.oracle.com/docs/cd/E14571_01/apirefs.1111/e13951/core/index.html
有了MBean参考手册，想要监控什么指标，直接到里面找，纯粹是体力活，剩下的就是考虑怎么把代码写得简单可用（Clean code that works ）了
只要有了这几个地址，开发监控WebLogic 9.x和10.x的项目就变得简单了。想当年，我就是在找资料上花费了大把大把的时间，而且那绝对是相当的痛苦。如果你不是第一时间看到了这篇文章，相信你一定感同身受吧！但是恭喜你，现在你不用那么痛苦了，哈哈，开个玩笑……
访问WebLogic使用的JAR包
◆ 访问WebLogic 9.x所使用的JAR包：
wlclient.jar、wljmxclient.jar
在%WL_HOME%\server\lib目录下
◆ 访问WebLogic 10.x所使用的JAR包：
由于10.x的API有变化，必须使用JarBuilder Tool生成wlfullclient.jar，具体参见官方的教程，上面的“葵花宝典”里面有链接。
◆ 监控所依赖的JAR包的存放位置
我们会通过这种方式获取和MBean Server的连接：
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JMXConnector connector = JMXConnectorFactory.connect(serviceURL, h);
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代码在Eclipse下通过Java程序调用没有任何问题，作为Web应用部署到Tocmat就出问题了，会报如下异常：
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Unsupported protocol: t3
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具体原因如下（这是找了很久以后在一个国外的论坛上看到的）：
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Here's the issue that I'm facing:
To get a JMX connection using JMXConnectionFactory using below: JMXConnector connector = JMXConnectorFactory.connect(serviceURL, h);
I have to rely on classes in weblogic.jar
That is because the implementation of JMXConnector is in weblogic.jar. However, the interface/abstract class for JMXConnectionFactory lives in rt.jar that comes with JDK1.5 or JDK1.6.
Because rt.jar is (probably) used by the bootstrap classloader, I HAVE to include weblogic.jar in the CATALINA_HOME/common/lib directory. If I do so, I can get the JMX part of the solution to work because both, rt.jar and weblogic.jar are loaded by the same (system) classloader.
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解决办法很简单： 将wlfullclient.jar放到Tomcat安装目录下的lib目录下即可。
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刚发现这个问题时很是诧异，始终想不通，后来在老外的一个论坛上找到类似问题，原来， JMXConnector接口是在JDK1.5/JDK1.6的rt.jar里面，而具体实现是在wlfullclient.jar里面。问题就在这里， rt.jar是由系统类加载器加载的， wlfullclient.jar如果放在自己的WEB-INFO/lib目录下，就是由WebappClassLoader去加载了。所以我们将wlfullclient.jar放到Tomcat安装目录下的lib目录下，这样wlfullclient.jar跟rt.jar就是由同一个classloader加载的了，所以问题就迎刃而解了。
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一个Demo：采集Web应用的Servlet信息
public class MonitorServlets {
private static MBeanServerConnection connection;
private static JMXConnector connector;
private static final ObjectName service;
// Initializing the object name for DomainRuntimeServiceMBean
// so it can be used throughout the class.
static {
try {
service = new ObjectName(
"com.bea:Name=DomainRuntimeService,Type=weblogic.management.mbeanservers.domainruntime.DomainRuntimeServiceMBean");
} catch (MalformedObjectNameException e) {
throw new AssertionError(e.getMessage());
}
}
/**
* 测试本地的WebLogic10.3
*/
public static void main1(String[] args) throws Exception {
String hostname = "localhost";
String portString = "7001";
String username = "weblogic";
String password = "weblogic123";
MonitorServlets monitor = new MonitorServlets();
initConnection(hostname, portString, username, password);
monitor.getServletData();
connector.close();
}
/**
* 测试192.168.1.5服务器上的WebLogic9.2
*/
public static void main(String[] args) throws Exception {
String hostname = "192.168.1.5";
String portString = "7001";
String username = "weblogic";
String password = "weblogic";
MonitorServlets monitor = new MonitorServlets();
initConnection(hostname, portString, username, password);
monitor.getServletData();
connector.close();
}
/**
* Initialize connection to the Domain Runtime MBean Server
*
* @param hostname
* @param portString
* @param username
* @param password
* @throws IOException
* @throws MalformedURLException
*/
public static void initConnection(String hostname, String portString,
String username, String password) throws IOException,
MalformedURLException {
String protocol = "t3";
Integer portInteger = Integer.valueOf(portString);
int port = portInteger.intValue();
String jndiroot = "/jndi/";
String mserver = "weblogic.management.mbeanservers.domainruntime";
JMXServiceURL serviceURL = new JMXServiceURL(protocol, hostname, port,
jndiroot + mserver);
Hashtable<String, String> h = new Hashtable<String, String>();
h.put(Context.SECURITY_PRINCIPAL, username);
h.put(Context.SECURITY_CREDENTIALS, password);
h.put(JMXConnectorFactory.PROTOCOL_PROVIDER_PACKAGES,
"weblogic.management.remote");
connector = JMXConnectorFactory.connect(serviceURL, h);
connection = connector.getMBeanServerConnection();
}
/**
* Get an array of ServerRuntimeMBeans
*
* @return
* @throws Exception
*/
public static ObjectName[] getServerRuntimes() throws Exception {
return (ObjectName[]) connection
.getAttribute(service, "ServerRuntimes");
}
/**
* Get an array of WebApplicationComponentRuntimeMBeans
*
* @throws Exception
*/
public void getServletData() throws Exception {
ObjectName[] serverRT = getServerRuntimes();
int length = (int) serverRT.length;
for (int i = 0; i < length; i++) {
System.out
.println("===========================================ServerRuntimes");
String name = (String) connection.getAttribute(serverRT[i], "Name");
String state = (String) connection.getAttribute(serverRT[i],
"State");
System.out.println("Server name: " + name + ".Server state: "
+ state);
ObjectName[] appRT = (ObjectName[]) connection.getAttribute(
serverRT[i], "ApplicationRuntimes");
int appLength = (int) appRT.length;
for (int x = 0; x < appLength; x++) {
System.out
.println("-------------------------------------------ApplicationRuntimes");
System.out.println("Application name: "
+ (String) connection.getAttribute(appRT[x], "Name"));
ObjectName[] compRT = (ObjectName[]) connection.getAttribute(
appRT[x], "ComponentRuntimes");
int compLength = (int) compRT.length;
for (int y = 0; y < compLength; y++) {
String componentName = (String) connection.getAttribute(
compRT[y], "Name");
String componentType = (String) connection.getAttribute(
compRT[y], "Type");
System.out.println(" Component name: " + componentName
+ " , Component type: " + componentType);
if (componentType.toString().equals(
"WebAppComponentRuntime")) {
ObjectName[] servletRTs = (ObjectName[]) connection
.getAttribute(compRT[y], "Servlets");
int servletLength = (int) servletRTs.length;
for (int z = 0; z < servletLength; z++) {
System.out.println(" Servlet name: "
+ (String) connection.getAttribute(
servletRTs[z], "Name"));
System.out.println(" Servlet context path: "
+ (String) connection.getAttribute(
servletRTs[z], "ContextPath"));
System.out
.println(" Invocation Total Count : "
+ (Object) connection.getAttribute(
servletRTs[z],
"InvocationTotalCount"));
}
}
}
}
}
}
}