Java转换流(InputStreamReader/OutputStreamWriter)的使用

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class CodeQuestion {
    public static void main(String[] args) {
        //读取E盘下a.txt文件
        String filePath = "E:\\a.txt";
        BufferedReader bufferedReader = null;

        try {
            bufferedReader = new BufferedReader(new FileReader(filePath));
            String file = bufferedReader.readLine();
            System.out.println(file);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bufferedReader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

import java.io.*;

public class InputStreamReader_ {
    public static void main(String[] args) {
        String filePath = "E:\\a.txt";
        BufferedReader bufferedReader = null;
        try {
            InputStreamReader gbk = new InputStreamReader(new FileInputStream(filePath), "GBK");
            bufferedReader = new BufferedReader(gbk);
            //下面为第二种写法，通常使用第二种
            //bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream(filePath),"GBK"));
            String s;
            while ((s = bufferedReader.readLine()) != null) {
                System.out.println(s);
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bufferedReader.close();//关闭外层流即可
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

import java.io.*;

public class OutputStreamWriter_ {
    public static void main(String[] args) {
        String filePath = "E:\\test.txt";
        OutputStreamWriter utf8 = null;
        try {
            utf8 = new OutputStreamWriter(new FileOutputStream(filePath), "UTF8");
            try {
                utf8.write("hello世界");
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } finally {
            try {
                utf8.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            System.out.println("按照utf-8保存文件成功");
        }
    }
}