Java从文本里读取信息截取一部分转成int型进行排序

test_5
test_3
test_2
test_10

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;

/**
 * webkfa.com
 * @author 学到老
 *
 */
public class Test {
	
	public static void main(String[] args) {
		BufferedReader is=null;
		try {
			is = new BufferedReader(new FileReader("c:/1.txt"));
		} catch (FileNotFoundException e2) {
			// TODO Auto-generated catch block
			e2.printStackTrace();
		}
		try {
			int i=0;
			String s="";
			ArrayList list=new ArrayList();
			while(null != (s=is.readLine())){
				list.add(s.split("_")[1]);
			}
			//从文本里面读出来的顺序
			System.out.println("排序前:");
			int[] a = new int[list.size()];
			for (int j = 0; j < list.size(); j++) {
				a[j]=Integer.parseInt(list.get(j).toString());
				System.out.println(list.get(j));
			}
			Arrays.sort(a);
			System.out.println("排序后:");
			for (int j = 0; j < a.length; j++) {
				System.out.println(a[j]);
			}
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
			
		}
	}
}