Here is a small program to extract the java compile version from a java .class file.
It is based on the info from: http://en.wikipedia.org/wiki/Class_%28file_format%29
JDK v d HEX
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J2SE 6.0=50 - 32
J2SE 5.0=49 - 31
JDK 1.4=48 - 30
JDK 1.3=47 - 29
JDK 1.2=46 - 28
JDK 1.1=45 - 27
527385a1-9076-4532-9b89-6ccacebab823|0|.0
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