This paper presents a new approach to the issues of performance monitoring and visualization of distributed applications using the J-OCM monitoring system. We are focusing on the building of a GUI measurement-oriented tool with a flexible functionality, Java Measurement Tool (JMT) on top of J-OCM which provides an OMIS-based monitoring interface. The tool addresses the issues of user-defined metrics and user-friendly visualization of distributed Java applications. The paper introduces the functionality, design, and status of JMT