Check Java Binary Version

檢視Java Binary File編譯版本

方法一:
>javap -verbose Employee
Compiled from "Employee.java"
public class test.Employee extends java.lang.Object
  SourceFile: "Employee.java"
  minor version: 0
  major version: 50
  Constant pool:
.....


方法二:
使用文字工具開啟class檔案,檢視前面的binary code
javac -target 1.1 ==> CA FE BA BE 00 03 00 2D
javac -target 1.2 ==> CA FE BA BE 00 00 00 2E
javac -target 1.3 ==> CA FE BA BE 00 00 00 2F
javac -target 1.4 ==> CA FE BA BE 00 00 00 30
看起來新版本就往下推最後一碼了... :P