View Compilation Error

0_0_28210130_8444\Main.java:1: 错误: 需要class, interface或enum
public static void main(String[] args) {
              ^
0_0_28210130_8444\Main.java:4: 错误: 需要class, interface或enum
		Integer a,b;
		^
0_0_28210130_8444\Main.java:5: 错误: 需要class, interface或enum
		while(in.hasNext())
		^
0_0_28210130_8444\Main.java:8: 错误: 需要class, interface或enum
			b=in.nextInt();
			^
0_0_28210130_8444\Main.java:9: 错误: 需要class, interface或enum
			System.out.println(Math.abs(a));
			^
0_0_28210130_8444\Main.java:10: 错误: 需要class, interface或enum
			System.out.println(Math.abs(b));
			^
0_0_28210130_8444\Main.java:11: 错误: 需要class, interface或enum
		}
		^
7 个错误