java转换流

　　转换流是把字节流转换成字符流，比如往一个文件中写内容，原本是一个字节一个字节的写，转换为字符流后，我们可以一个字符串，一个字符串的写，书写中文很方便

　　转换流class： OutputStreamWriter，InputStreamReader，需要和OutputStream/inputStream套接，并且在构造是可以指定其编码

 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.OutputStreamWriter;

 public class TestTransForm1 {

     /**
      * @param args
      * @throws IOException
      */
     public static void main(String[] args) throws IOException {

         String path="D:"+File.separator+"trans.txt";
         OutputStreamWriter osw = new OutputStreamWriter(new FileOutputStream(path,true),"ISO8859_1");
         osw.write("test");
         osw.flush();
         System.out.println(osw.getEncoding());
         osw.close();

     }

 }

输出结果：ISO8859_1

trans.txt中的内容：test

 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;

 public class TestTransForm2 {

     /**
      * @param args
      * @throws IOException
      */
     public static void main(String[] args) throws IOException {
         InputStreamReader isr=new InputStreamReader(System.in);
         BufferedReader br=new BufferedReader(isr);
         String s=null;
         s=br.readLine();
         while(s!=null){
             if(s.equalsIgnoreCase("exit")){
                 break;
             }

             System.out.println(s.toUpperCase());
             s=br.readLine();//将s重新指向键盘输入
         }
         isr.close();
         br.close();
     }

 }

输出结果：

aaarticlea/png;base64,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" alt="" />