Research On Dynamic Monitor System Based On The Execution Event Of JVM

With the development of information technology, Java is more and more widely usedin programming. On one hand, it improves the design quality and efficiency ofprogramming. On the other hand, it increases the complexity of software and makesfinding bugs especially in multi-threads programs more and more difficult. Dynamicmonitoring has two advantages: high accuracy and it can monitor in real-time way, so it isresearched by many. Dynamic monitoring based on the execution event of JVM candeep into the internal virtual machine and can get much effective run-time information,which is worth research.JVM is the execution environment of java programs. We can get much run-timeinformation such as method area, heap, and java stack if deep into JVM. The dynamicmonitoring system which based on the execution event of JVM implements the JVMinternal data structure and modifies the execution engine and introduces many events suchas byte code execution during execution. The monitoring program can analysis therun-time status and find bugs by subscribing these events. As parallel bugs is closelyrelated with the byte code execution sequence between threads, in order to promote theaccuracy of finding bugs, the monitoring system uses mode checking technology and cantraverses all the program state spaces. The monitoring system can detect dead lock, datarace, monitor method execution and analyze class coverage information. The monitoringsystem can be divided into four parts, VM subsystem, Monitor subsystem,Communication subsystem and UI.Experiments demonstrate that the monitor system can get good results on monitoringsmall and middle-sized programs and the accuracy is high.