转换流

转换流
InputStreamReader
OutputStreamWriter
属于 1.处理流 2.字符流
作用：用来转换 字节流到字符流，或者字符流到字节流

从字节流读成字符流 输出到控制台

package com.daijunyi.file;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
/**
 *转换流
 * InputStreamReader
 * OutputStreamWriter
 *
 * 属于 1.处理流 2.字符流
 * 作用：用来转换 字节流到字符流，或者字符流到字节流
 * */
public class InputStreamReaderTest {
    public static void main(String[] args) {
        InputStreamReader isr = null;//属于直接用默认的编码集
        try {
            FileInputStream fis = new FileInputStream("hello.txt");
            isr = new InputStreamReader(fis);
            char[] buffer = new char[10];
            int len;
            while ((len = isr.read(buffer)) != -1){
                System.out.print(new String(buffer,0,len));
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (isr != null){
                    isr.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

utf-8格式的文本文件，转换成gbk编码的文本文件

package com.daijunyi.file;

import java.io.*;

public class OutputStreamWriterTest {

    public static void main(String[] args) {
        InputStreamReader isr = null;
        OutputStreamWriter osw = null;
        try {
            FileInputStream fis = new FileInputStream("hello.txt");
            FileOutputStream fos = new FileOutputStream("hello2.txt");

            isr = new InputStreamReader(fis, "utf-8");
            osw = new OutputStreamWriter(fos, "gbk");

            char[] buffer = new char[10];
            int len;
            while ((len = isr.read(buffer)) != -1){
                osw.write(buffer,0,len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            try {
                if (isr != null){
                    isr.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if (osw != null){
                    osw.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }


    }

}