如果要查看lambda主体的代码
a*a+2*a+1，则应调用
javap -c -v -p t以查看 私有 方法：
private static java.lang.Integer lambda$main$0(java.lang.Integer);descriptor: (Ljava/lang/Integer;)Ljava/lang/Integer;flags: ACC_PRIVATE, ACC_STATIC, ACC_SYNTHETICCode: stack=3, locals=1, args_size=1 0: aload_0 1: invokevirtual #7 // Method java/lang/Integer.intValue:()I 4: aload_0 5: invokevirtual #7 // Method java/lang/Integer.intValue:()I 8: imul 9: iconst_2 10: aload_0 11: invokevirtual #7 // Method java/lang/Integer.intValue:()I 14: imul 15: iadd 16: iconst_1 17: iadd 18: invokestatic #4 // Method java/lang/Integer.valueOf:(I)Ljava/lang/Integer; 21: areturn LineNumberTable: line 4: 0
