Eclipse普通java Project文件路径问题

项目的结构如图

读取src里某个包下的文件，代码如下

BufferedReader br=new BufferedReader(new FileReader("src/ch01/practice1/input.txt"));

输出到同一目录下，代码如下

PrintWriter pw=new PrintWriter("src/ch01/practice1/output.txt");

整个算法代码如下

package ch01.practice1;

import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

import java.io.PrintWriter;

//import java.util.Arrays;

//统计数字问题

public class PageNuber

{

	public static void main(String[] args) throws IOException

	{

		BufferedReader br=new BufferedReader(new FileReader("src/ch01/practice1/input.txt"));

		String line=br.readLine();

		if (null!=line)

		{

			int n=Integer.valueOf(line);

			int[] arr= new int[10];

//			Arrays.fill(arr,0);

//			System.out.println(Arrays.toString(arr));

			for (int i = 1; i < n+1; i++)

			{

				int div=i;

				while(div>0)

				{

					arr[div%10]++;

					div=div/10;

				}

			}

//			System.out.println(Arrays.toString(arr));

			PrintWriter pw=new PrintWriter("src/ch01/practice1/output.txt");

			for (int i = 0; i < arr.length; i++)

			{

				pw.print(arr[i]+" ");

			}

			pw.close();

		}

		br.close();

	}

}