java - 如何使用java打印起始行号

Question

在此代码中，我试图打印起始行号。在这里，我正在读取文本文件中的值并将这些值相加。但我正在尝试从开始计数的地方获取行号..

我该怎么做？

代码

import java.io.*;

class CountR
{
    public static void main(String args[])
    {
        setForSum("read.txt",7);
    }

    public static void setForSum(String filename,int param2)
    {
        try
        {
            FileInputStream fstream = new FileInputStream(filename);
            BufferedReader br = new BufferedReader(new InputStreamReader(fstream));
            String strLine;
            int i = 0;
            int sum=0; 
            int startline=0;
            System.out.println(param2+": Is in");
            while ((strLine = br.readLine()) != null)   
            {
                ++i;
                startline = i;
                int line = Integer.parseInt(strLine);
                sum=sum+line;
                System.out.println("Sum= "+sum);
                if(sum>=param2)
                {                 
                    /* System.out.println("line number : "+i);*/ 
                    System.out.println("Start line number :"+startline+" End line number:" +i);
                    sum =0;
                }                                
            }            
            in.close();
        }
        catch (Exception e)
        {
            System.err.println("Error: " + e.getMessage());
        }
    }
}

read.txt 文件

1
2
3
4
1
2
3
1
2
3
1
2
3
1
2
3
1
2
3
1
2
3
1
2
3

我现在得到的输出是这样的。

Sum= 1
Sum= 3
Sum= 6
Sum= 10
Start line number :4 End line number:4
Sum= 1
Sum= 3
Sum= 6
Sum= 7
Start line number :8 End line number:8
Sum= 2
Sum= 5
Sum= 6
Sum= 8
Start line number :12 End line number:12
Sum= 3
Sum= 4
Sum= 6
Sum= 9
Start line number :16 End line number:16
Sum= 1
Sum= 3
Sum= 6
Sum= 7
Start line number :20 End line number:20
Sum= 2
Sum= 5
Sum= 6
Sum= 8
Start line number :24 End line number:24
Sum= 3

但应该是

    Sum= 1
    Sum= 3
    Sum= 6
    Sum= 10
    Start line number :1 End line number:4
    Sum= 1
    Sum= 3
    Sum= 6
    Sum= 7
    Start line number :5 End line number:8
    Sum= 2
    Sum= 5
    Sum= 6
    Sum= 8
    Start line number :9 End line number:12
    Sum= 3
    Sum= 4
    Sum= 6
    Sum= 9
    Start line number :13 End line number:16
    Sum= 1
    Sum= 3
    Sum= 6
    Sum= 7
    Start line number :17 End line number:20
    Sum= 2
    Sum= 5
    Sum= 6
    Sum= 8
    Start line number :21 End line number:24
    Sum= 3

Answer 1

您没有在任何地方重置 startline。使用以下内容:

       while ((strLine = br.readLine()) != null)   
        {
            ++i;
            if(startline == 0) // set startline only if startline is zero, which will happen the first time and everytime you've printed the status
                startline = i;
            int line = Integer.parseInt(strLine);
            sum=sum+line;
            System.out.println("Sum= "+sum);
            if(sum>=param2)
            {                 
                /* System.out.println("line number : "+i);*/ 
                System.out.println("Start line number :"+startline+" End line number:" +i);
                sum =0;
                startline = 0;  // reset startline here
            }                                
        }