tomcat如何使用jmx查看webapp运行情况呢?

下文笔者讲述查看tomcat中webapp的运行情况简介说明，如下所示

实现思路:
     借助JMX即可实现查看tomcat中程序的运行情况

例:
在Tomcat5中，可以在bin目录下找点jmx.jar,4.1.X版本,server/lib/mx4j-jmx.jar
使用以下代码，即可输出webapp的运行情况

<%@page contentType=”text/plain;charset=GBK”%>
<%@page import=”java.util.Iterator”%>
<%@page import=”java.util.Set”%>
<%@page import=”javax.management.MBeanServerFactory”%>
<%@page import=”javax.management.MBeanServer”%>
<%@page import=”javax.management.ObjectName”%>
<%@page import=”javax.management.MBeanInfo”%>
<%@page import=”javax.management.MBeanAttributeInfo”%>
<%
out.clear();
 
MBeanServer mBeanServer = null;
if(MBeanServerFactory.findMBeanServer(null).size() > 0){
  mBeanServer = (MBeanServer)MBeanServerFactory.findMBeanServer(null).get(0);
}else{
  mBeanServer = MBeanServerFactory.createMBeanServer();
}
 
Set names = null;
try {
  names=mBeanServer.queryNames(new ObjectName(“*:j2eeType=WebModule,*”), null);
  out.println(“OK – Number of results: ” + names.size());
  out.println();
} catch (Exception e) {
  out.println(“Error – ” + e.toString());
  return;
}
 
Iterator it=names.iterator();
while( it.hasNext()) {
  ObjectName oname=(ObjectName)it.next();
  out.println( “Name: ” + oname.toString());
  
  try {
    MBeanInfo minfo=mBeanServer.getMBeanInfo(oname);
    // can’t be null – I thinl
    String code=minfo.getClassName();
    if (“org.apache.commons.modeler.BaseModelMBean”.equals(code)) {
      code=(String)mBeanServer.getAttribute(oname, “modelerType”);
    }
    out.println(“modelerType: ” + code);
    
    MBeanAttributeInfo attrs[]=minfo.getAttributes();
    Object value=null;
    
    for( int i=0; i< attrs.length; i++ ) {
      if( ! attrs[i].isReadable() ) continue;
      //if( ! isSupported( attrs[i].getType() )) continue;
      String attName=attrs[i].getName();
      if( attName.indexOf( “=”) >=0 ||
        attName.indexOf( “:”) >=0 ||
        attName.indexOf( ” “) >=0 )
      {
        continue;
      }
      
      try {
        value=mBeanServer.getAttribute(oname, attName);
      } catch( Throwable t) {
        System.out.println(“Error getting attribute ” + oname +
        ” ” + attName + ” ” + t.toString());
        continue;
      }
      if( value==null ) continue;
      if( “modelerType”.equals( attName)) continue;
      String valueString=value.toString();
      //out.println( attName + “: ” + escape(valueString));
      out.println( attName + “: ” + valueString);
    }
  } catch (Exception e) {
    
  }
  out.println();
}
%>