Introduction of transformation flow

InputStreamReader And OutputStreamWriter  It is also a processing flow  

package TransformStream;

import org.junit.Test;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;

public class InputStreamReaderTest {
    @Test
    public void test1() throws IOException {
        FileInputStream fis = new FileInputStream("hello2.txt");
//         Use the default character set   take   Data conversion of byte stream ( stay IDEA Medium is the default UTF-8)
        InputStreamReader isr = new InputStreamReader(fis);

//         Specify character set   take   Data conversion of byte stream 
//        InputStreamReader isr = new InputStreamReader(fis,"gbk");



        char[] buffer = new char[5];
        int len ;
        while((len = isr.read(buffer))!=-1){
            String str= new String(buffer);
            System.out.print(buffer);
        }
//       Transformation flow is also processing flow , So just close the outer layer 
        isr.close();
    }
}

OutputStreamWriter

//    OutputStreamWriter
    @Test
    public void test2() throws IOException {
        FileReader fr = new FileReader("hello2.txt");
        FileOutputStream fos = new FileOutputStream("hello3.txt");

        OutputStreamWriter osw = new OutputStreamWriter(fos,"gbk");

        char[] buffer = new char[5];
        int len;
        while((len = fr.read(buffer))!=-1){
            osw.write(buffer,0,len);
        }

        fr.close();
        osw.close();
    }