P6 EPPM Web Services has the following system requirements for installation:
Java Runtime Environment Requirements
Before installing P6 EPPM Web Services, you need to install the Java Development Kit (JDK), version 1.6.x, also known as J2SE 6.0. While P6 EPPM Web Services is compatible with any 1.6 version, Oracle recommends that you use Update 27. The Integrated Development Environment (IDE) you use to create code must work with this version.