程式設計題目：

3.向list集合新增姓名{張三,李四,王五,二丫,錢六,孫七},將二丫替換為王小丫,寫入到”D:\stuinfo.txt”。

示例程式碼：

package program.stream.exercise03;

import java.io.*;
import java.util.*;

/**
 * 3.向list集合新增姓名{張三,李四,王五,二丫,錢六,孫七},將二丫替換為王小丫,寫入到"D:\\stuinfo.txt"
**/

public class ListWriter {
    public static void main(String[] args) {

        List<String> list = new
 
 ArrayList<String>();

        //向list集合新增姓名{張三,李四,王五,二丫,錢六,孫七},
        list.add("張三");
        list.add("李四");
        list.add("王五");
        list.add("二丫");
        list.add("錢六");
        list.add("孫七");

        System.out.println("List修改前遍歷：");
        for(String s : list){
            System.out.println(s);
        }

        //將二丫替換為王小丫,
 

        list.set(3, "王小丫");

        System.out.println("List修改後遍歷：");
        Iterator<String> iterator = list.iterator();
        while (iterator.hasNext()) {
            String s = (String) iterator.next();
            System.out.println(s);
        }

        //寫入到"D:\\stuinfo.txt"
        Writer write = null
 
;
        BufferedWriter bufferedWriter = null;

        try {
            write = new FileWriter("D:\\stuinfo.txt");
            bufferedWriter = new BufferedWriter(write);

            for(int i=0;i<list.size();i++){
                bufferedWriter.write(list.get(i)+"\r\n");//寫入換行
            }
            System.out.println("寫入完成！");

        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            try {
                bufferedWriter.flush();
                write.flush();
                bufferedWriter.close();
                write.close();

            } catch (Exception e) {
                e.printStackTrace();
            }
        }

    }

}

結果顯示：