public class ServerImpl
{
public final long startTime;
public ServerImpl()
{
startTime = System.currentTimeMillis();
}
}
public class ServerMonitor implements ServerMonitorMBean
{
private final ServerImpl target;
public ServerMonitor(ServerImpl target)
{
this.target = target;
}
public long getUpTime()
{
return System.currentTimeMillis() - target.startTime;
}
}
import javax.management.MBeanServer;
import javax.management.MBeanServerFactory;
import javax.management.ObjectName;
public class Main
{
private static ObjectName objectName ;
private static MBeanServer mBeanServer;
public static void main(String[] args) throws Exception
{
init();
manage();
}
private static void init() throws Exception
{
ServerImpl serverImpl = new ServerImpl();
ServerMonitor serverMonitor = new ServerMonitor(serverImpl);
mBeanServer = MBeanServerFactory.createMBeanServer();
objectName = new ObjectName("objectName:id=ServerMonitor1");
mBeanServer.registerMBean(serverMonitor,objectName);
}
private static void manage() throws Exception
{
Long upTime = (Long) mBeanServer.getAttribute(objectName,"upTime");
System.out.println(upTime);
}
}
DynamicMBean:动态代理构建
import javax.management.*;
import java.lang.reflect.*;
public class ServerMonitor implements DynamicMBean
{
private final ServerImpl target;
private MBeanInfo mBeanInfo;
public ServerMonitor(ServerImpl target)
{
this.target = target;
}
// 实现获取被管理的 ServerImpl 的 upTime
public long upTime()
{
return System.currentTimeMillis() - target.startTime;
}
//javax.management.MBeanServer 会通过查询 getAttribute("Uptime") 获得
"Uptime" 属性值
public Object getAttribute(String attribute) throws AttributeNotFoundException,
MBeanException, ReflectionException
{
if(attribute.equals("UpTime"))
{
return upTime();
}
return null;
}
// 给出 ServerMonitor 的元信息。
public MBeanInfo getMBeanInfo()
{
if (mBeanInfo == null)
{
try
{
Class cls = this.getClass();
// 用反射获得 "upTime" 属性的读方法
Method readMethod = cls.getMethod("upTime", new Class[0]);
// 用反射获得构造方法
Constructor constructor = cls.getConstructor(new Class[]{ServerImpl.class});
// 关于 "upTime" 属性的元信息 : 名称为 UpTime,只读属性 ( 没有写方法 )。
MBeanAttributeInfo upTimeMBeanAttributeInfo = new MBeanAttributeInfo("UpTime", "The time span since server start",readMethod, null);
// 关于构造函数的元信息
MBeanConstructorInfo mBeanConstructorInfo = new MBeanConstructorInfo("Constructor for ServerMonitor", constructor);
//ServerMonitor 的元信息,为了简单起见,在这个例子里,
// 没有提供 invocation 以及 listener 方面的元信息
mBeanInfo = new MBeanInfo(cls.getName(),"Monitor that controls the server",
new MBeanAttributeInfo[] { upTimeMBeanAttributeInfo },
new MBeanConstructorInfo[] { mBeanConstructorInfo },
null, null);
}
catch (Exception e)
{
throw new Error(e);
}
}
return mBeanInfo;
}
public AttributeList getAttributes(String[] arg0)
{
return null;
}
public Object invoke(String arg0, Object[] arg1, String[] arg2) throws MBeanException,ReflectionException
{
return null;
}
public void setAttribute(Attribute arg0) throws AttributeNotFoundException, InvalidAttributeValueException, MBeanException, ReflectionException
{
return;
}
public AttributeList setAttributes(AttributeList arg0)
{
return null;
}
}
Open MBean:开放式构建管理
略
ModelMBean:
public class Server
{
private long startTime;
public Server() { }
public int start()
{
startTime = System.currentTimeMillis();
return 0;
}
public long getUpTime()
{
return System.currentTimeMillis() - startTime;
}
}
import javax.management.*;
import javax.management.modelmbean.*;
public class Main
{
public static void main(String[] args) throws Exception
{
MBeanServer mBeanServer = MBeanServerFactory.createMBeanServer();
RequiredModelMBean serverMBean = (RequiredModelMBean) mBeanServer.instantiate(
"javax.management.modelmbean.RequiredModelMBean");
ObjectName serverMBeanName = new ObjectName("server: id=Server");
serverMBean.setModelMBeanInfo(getModelMBeanInfoForServer(serverMBeanName));
Server server = new Server();
serverMBean.setManagedResource(server, "ObjectReference");
ObjectInstance registeredServerMBean = mBeanServer.registerMBean((Object) serverMBean, serverMBeanName);
serverMBean.invoke("start",null, null);
Thread.sleep(1000);
System.out.println(serverMBean.getAttribute("upTime"));
Thread.sleep(5000);
System.out.println(serverMBean.getAttribute("upTime"));
}
private static ModelMBeanInfo getModelMBeanInfoForServer(ObjectName objectName)throws Exception
{
ModelMBeanAttributeInfo[] serverAttributes = new ModelMBeanAttributeInfo[1];
Descriptor upTime = new DescriptorSupport(
new String[] {
"name=upTime",
"descriptorType=attribute",
"displayName=Server upTime",
"getMethod=getUpTime",
});
serverAttributes[0] = new ModelMBeanAttributeInfo(
"upTime",
"long",
"Server upTime",
true,
false,
false,
upTime
);
ModelMBeanOperationInfo[] serverOperations = new ModelMBeanOperationInfo[2];
Descriptor getUpTimeDesc = new DescriptorSupport(
new String[] {
"name=getUpTime",
"descriptorType=operation",
"class=modelmbean.Server",
"role=operation"
});
MBeanParameterInfo[] getUpTimeParms = new MBeanParameterInfo[0];
serverOperations[0] = new ModelMBeanOperationInfo("getUpTime",
"get the up time of the server",
getUpTimeParms,
"java.lang.Long",MBeanOperationInfo.ACTION,
getUpTimeDesc
);
Descriptor startDesc = new DescriptorSupport(
new String[] {
"name=start",
"descriptorType=operation",
"class=modelmbean.Server",
"role=operation"
});
MBeanParameterInfo[] startParms = new MBeanParameterInfo[0];
serverOperations[1] = new ModelMBeanOperationInfo(
"start",
"start(): start server",
startParms,
"java.lang.Integer",
MBeanOperationInfo.ACTION,
startDesc
);
ModelMBeanInfo serverMMBeanInfo = new ModelMBeanInfoSupport(
"modelmbean.Server",
"ModelMBean for managing an Server",
serverAttributes,
null,
serverOperations,
null
);
//Default strategy for the MBean.
Descriptor serverDescription = new DescriptorSupport(
new String[]
{
("name=" + objectName),
"descriptorType=mbean",
("displayName=Server"),
"type=modelmbean.Server",
"log=T",
"logFile=serverMX.log",
"currencyTimeLimit=10"
}
);
serverMMBeanInfo.setMBeanDescriptor(serverDescription);
return serverMMBeanInfo;
}
}