JMXProxyServlet
This servlet will dump JMX attributes in a simple format
用于查询 jmx beans 

https://tomcat.apache.org/tomcat-8.0-doc/manager-howto.html#Using_the_JMX_Proxy_Servlet


查询语法


返回所有 bean
qry=*:*

返回 java.lang 域 所有bean
qry=java.lang:*

qry=java.lang:type=OperatingSystem

get=java.lang:type=OperatingSystem&att=SystemLoadAverage

qry=java.lang:type=MemoryPool,*



qry=java.lang:type=MemoryPool,name=Metaspace

OK - Number of results: 1

Name: java.lang:type=MemoryPool,name=Metaspace
modelerType: sun.management.MemoryPoolImpl
Name: Metaspace
Type: NON_HEAP
Valid: true
Usage: javax.management.openmbean.CompositeDataSupport(compositeType=javax.management.openmbean.CompositeType(name=java.lang.management.MemoryUsage,items=((itemName=committed,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)),(itemName=init,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)),(itemName=max,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)),(itemName=used,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)))),contents={committed=24510464, init=0, max=-1, used=23899320})
PeakUsage: javax.management.openmbean.CompositeDataSupport(compositeType=javax.management.openmbean.CompositeType(name=java.lang.management.MemoryUsage,items=((itemName=committed,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)),(itemName=init,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)),(itemName=max,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)),(itemName=used,itemType=javax.management.openmbean.SimpleType(name=java.lang.Long)))),contents={committed=24510464, init=0, max=-1, used=23899320})
MemoryManagerNames: Array[java.lang.String] of length 1
	Metaspace Manager
UsageThreshold: 0
UsageThresholdExceeded: false
UsageThresholdCount: 0
UsageThresholdSupported: true
CollectionUsageThresholdSupported: false
ObjectName: java.lang:type=MemoryPool,name=Metaspace





获取属性
get=java.lang:type=OperatingSystem&att=SystemLoadAverage

OK - Attribute get 'java.lang:type=OperatingSystem' - SystemLoadAverage = 2.39892578125


get=java.lang:type=Memory&att=HeapMemoryUsage&key=init
OK - Attribute get 'java.lang:type=Memory' - HeapMemoryUsage - key 'init' = 2147483648