Java.io.LineNumberInputStream. getLineNumber() 方法

描述

java.io.LineNumberInputStream.getLineNumber() 方法返回当前行号。

声明

以下是 java.io.LineNumberInputStream.getLineNumber() 方法的声明 −

public int getLineNumber()

参数

NA

返回值

该方法返回当前行号。

异常

NA

示例

下面的例子展示了 java.io.LineNumberInputStream.getLineNumber() 方法的使用。

package com.tutorialspoint;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.LineNumberInputStream;

public class LineNumberInputStreamDemo {
   public static void main(String[] args) throws IOException {
      LineNumberInputStream lnis = null;
      FileInputStream fis = null;
      int i,j;
      char c;
      
      try {
         // create new input streams
         fis = new FileInputStream("C:/test.txt");
         lnis = new LineNumberInputStream(fis);
         
         // reads till the end of the stream
         while((i = lnis.read())!=-1) {
         
            // converts int to char
            c = (char)i;
            
            // if the character is not new line 
            if(i!=10) {
            
               // prints char
               System.out.print("Character read: "+c);
               
               // get the line number
               j = lnis.getLineNumber();
               System.out.println(" at line: "+j);
            }
         }
         
      } catch(Exception e) {
         // if any error occurs
         e.printStackTrace();
      } finally {
         // closes the stream and releases any system resources
         if(fis!=null)
            fis.close();
         if(lnis!=null)
            lnis.close();      
      }
   }
}

假设我们有一个文本文件c:/test.txt，其内容如下。 该文件将用作我们示例程序的输入 −

ABCDE

让我们编译并运行上面的程序，这将产生下面的结果 −

Character read: A at line: 0
Character read: B at line: 0
Character read: C at line: 0
Character read: D at line: 0
Character read: E at line: 0
Character read: F at line: 1
Character read: G at line: 1
Character read: H at line: 1
Character read: I at line: 1
Character read: J at line: 1
Character read: K at line: 2
Character read: L at line: 2
Character read: M at line: 2
Character read: N at line: 2
Character read: O at line: 2
Character read: P at line: 3
Character read: Q at line: 3
Character read: R at line: 3
Character read: S at line: 3
Character read: T at line: 3