因为经常会在写小程序中用到java 的 按行读写文件,所以在这就把模板站出来。
package com; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.File; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.ArrayList; public class Main { private static ArrayList<String> list = null; //获取对应操作系统的换行符 private final static String EOL = System.getProperty("line.separator"); /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub //模拟copy操作 String file_name = ""; readForLine(file_name); writeForLine(file_name + ".bak"); } //按行读取文件file_name,并把每一行的数据存储在list中 public static void readForLine(String file_name) { File file = new File(file_name); BufferedReader reader = null; try { reader = new BufferedReader(new FileReader(file)); String line = null; //按行读,并把每次读取的结果保存在line字符串中 while ( (line = reader.readLine()) != null ) { list.add(line); System.out.println(line); } //关闭流 reader.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally { //当由于异常情况,上面关闭流程序没有执行时 if ( reader != null ) { try { reader.close(); }catch(IOException e) { e.printStackTrace(); } } } } //按行写文件,将list中的字符串,按行写入file_name文件中 public static void writeForLine(String file_name) { File file = new File(file_name); BufferedWriter writer = null; try { writer = new BufferedWriter(new FileWriter(file)); for ( String elem: list ) { writer.write(elem + EOL);//按行写文件,后面追加行分隔符EOL } //关闭流 writer.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally { if ( writer != null ) { try { writer.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } }
原文地址:http://blog.csdn.net/chenwen_201116040110/article/details/42169141