Java实现缓冲流 编码 & 解码

Java 转换流：InputStreamReader & OutputStreamWriter

package com.io.review;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

import org.junit.Test;

/**
 * 转换流：InputStreamReader & OutputStreamWriter
 */
public class BufferedStreamCopy {

    /*
     * 编码 1 【编码：字符串 -> 字节数组】
     */
    @Test
    public void coding() {
        String str = "自定义编码 嘿 Siri ！";
        BufferedWriter bw = null;
        try {
            // 将str 写入当前项目下./hello.txt 文件中
            FileOutputStream fos = new FileOutputStream("./hello.txt");
            OutputStreamWriter osw = new OutputStreamWriter(fos, "UTF-8");// 此处也可指定编码格式
            bw = new BufferedWriter(osw);

            bw.write(str);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (bw != null) {
                try {
                    bw.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }

    /*
     * 解码 1 【解码：字节数组 -> 字符串】
     */
    @Test
    public void decode() {
        BufferedReader br = null;
        try {
            InputStream in = System.in;
            InputStreamReader isr = new InputStreamReader(in);
            br = new BufferedReader(isr);

            String str = null;
            while ((str = br.readLine()) != null) {
                System.out.println("---" + str);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /*
     * 解码 2
     * 
     * 从键盘输入字符串，要求将读取到的整行字符串转成大写输出。当输入“e”或者“exit”时，退出程序。
     */
    @Test
    public void decode2() {
        BufferedReader br = null;
        try {
            InputStream in = System.in;
            InputStreamReader sir = new InputStreamReader(in);
            br = new BufferedReader(sir);

            String str = null;
            while ((str = br.readLine()) != null) {
                // 忽略大小写判断是否 e或 exit
                if (str.equalsIgnoreCase("e") || str.equalsIgnoreCase("exit")) {
                    System.out.println("程序结束！！");
                    break;
                } else {
                    // 输入的字符转换成大写
                    String upperCase = str.toUpperCase();
                    System.out.println(upperCase);
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }

    /*
     * 解码 3
     */
    @Test
    public void decode3() {
        BufferedReader br = null;
        try {
            FileInputStream fis = new FileInputStream("./hello.txt");
            InputStreamReader isr = new InputStreamReader(fis, "UTF-8");
            br = new BufferedReader(isr);

            String str = null;
            while ((str = br.readLine()) != null) {
                System.out.println(str);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

}