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