4-标准输入输出流（转换流）

package com.io;

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

import org.junit.Test;

/*
 * 标准输出流  System.out 返回outStream
 *
 * 标准输入流 System.in 返回inputStream
 */
public class 标准输入输出流 {
    /*
     *  从控制台输入字符串，把字符串转换为大写，直至输入e或exit退出
     */
    @Test
    public void systemInOutTest() {
        BufferedReader br = null;
        try {
            InputStream is = System.in;
            InputStreamReader isr = new InputStreamReader(is, "GBK");// 需要把字节流转成字符流
            br = new BufferedReader(isr);

            String str;
            while (true) {
                str = br.readLine();
                if ("e".equalsIgnoreCase(str) || "exit".equalsIgnoreCase(str)) {
                    break;
                }
                System.out.println(str.toUpperCase());
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                br.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}