Today i will share the data for Java Version against Pentaho version. See the list below.It will help you in order to install correct Java version for Pentaho.

PDI Version Java Version
Pentaho 8.2| JDK 1.8
Pentaho 8.1| JDK 1.8
Pentaho 8.0| JDK 1.8
Pentaho 7.1| JDK 1.8
Pentaho 7.0| JDK 1.8
Pentaho 6.1| JDK 1.7
Pentaho 6.0| JDK 1.7
Pentaho 5.4| JDK 1.7
Pentaho 5.3| JDK 1.7
Pentaho 5.2| JDK 1.7
Pentaho 5.1| JDK 1.7