java之转换编码输出文本

package classtest;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;

public class Test1 {

//  1.利用转换流将GBK格式文件以UTF-8输出到其它文件。
    public void test() throws IOException {
        FileInputStream is=new FileInputStream("a.txt");
        InputStreamReader isr=new InputStreamReader(is,"GBK");
        FileOutputStream os=new FileOutputStream("b.txt");
        OutputStreamWriter isw=new OutputStreamWriter(os,"UTF-8");
        int read=-1;
        while ((read=isr.read())!=-1) {
            isw.write(read);
            isw.flush();
        }
        if(isr!=null) {
            isr.close();
        }
        if(isw!=null) {
            isw.close();
        }
    }
}