Java之IO转换流

import java.io.IOException;
import java.io.InputStream;
 
 
/**
 *读取键盘录入的数据，并打印在控制台上。
 *
 *键盘本身就是一个标准的输入设备，
 *对于Java而言，
 */
public class ReadKey {
 
 /**
  * @param args
  * @throws IOException
  */
 public static void main(String[] args) throws IOException {
// readKey();
  readKey_2();
 }
 
 public static void readKey() throws IOException {
  InputStream in = System.in;
 
  int ch = in.read();
  System.out.println(ch);
  int ch1 = in.read();
  System.out.println(ch1);
  int ch2 = in.read();
  System.out.println(ch2);
 
 }
 
 /**
  * 获取用户键盘录入的数据，
  * 并将数据变成大写显示在控制台上，
  * 如果用户输入的是over，则结束键盘录入
  *
  * 思路：
  * 1，因为键盘录入只读取一个字节，要判断是否是over，需要先将读到的字节拼成字符串 
  * 2，那就需要一个容器。可以使用StringBuilder
  * 3，在用户回车之前将录入的数据变成字符串判断即可。
  * @throws IOException
  */
 public static void readKey_2() throws IOException {
  //创建容器
  StringBuilder sb = new StringBuilder();
  //获取键盘读取流
  InputStream in = System.in;
  //定义变量记录读取到的字节，并循环读取。
  int ch = 0;
  while((ch = in.read())!=-1){
   //在存储之前需要判断是否是换行标记，因为换行标记不存
   if(ch == ‘\r‘)
    continue;
   if(ch == ‘\n‘){
    String temp = sb.toString();
    if("over".equals(temp))
     break;
    System.out.println(temp.toUpperCase());
    sb.delete(0,sb.length());
   }else{
    sb.append((char)ch);
   }
  }
 }
}
 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
 
public class TransStreamDemo {
 
 /**
  * @param args
  * @throws IOException
  */
 public static void main(String[] args) throws IOException {
  //字节流
  InputStream in = System.in;
  //将字节转换成字符的桥梁，即转换流。
  InputStreamReader isr = new InputStreamReader(in);
 
  //字符流
  BufferedReader bufr = new BufferedReader(isr);
  String line = null;
  while((line=bufr.readLine())!=null){
   if("over".equals(line)){
    break;
   }
   System.out.println(line.toUpperCase());
  }
 }
}

 
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
 
public class TransStreamDemo {
 
 /**
  * @param args
  * @throws IOException
  */
 public static void main(String[] args) throws IOException {
  //字节流
  InputStream in = System.in;
  //将字节转换成字符的桥梁，即转换流。
  InputStreamReader isr = new InputStreamReader(in);
 
  //字符流
  BufferedReader bufr = new BufferedReader(isr);
 
  OutputStream out = System.out;
  OutputStreamWriter osw = new OutputStreamWriter(out);
  BufferedWriter bufw = new BufferedWriter(osw);
 
  String line = null;
  while((line=bufr.readLine())!=null){
   if("over".equals(line)){
    break;
   }
   bufw.write(line.toUpperCase());
   bufw.newLine();
   bufw.flush();
  }
 }
}

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
 
public class TransStreamDemo {
 
 /**
  * @param args
  * @throws IOException
  */
 public static void main(String[] args) throws IOException {
  BufferedReader bufr = new BufferedReader(new InputStreamReader(System.in));
  BufferedWriter bufw = new BufferedWriter(new OutputStreamWriter(System.out)); 
  String line = null;
  while((line=bufr.readLine())!=null){
   if("over".equals(line)){
    break;
   }
   bufw.write(line.toUpperCase());
   bufw.newLine();
   bufw.flush();
  }
 }
}
 

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
 
public class TransStreamDemo {
 
 /**
  * @param args
  * @throws IOException
  */
 public static void main(String[] args) throws IOException {
  BufferedReader bufr = new BufferedReader(new InputStreamReader(new FileInputStream("a.txt")));
  BufferedWriter bufw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("b.txt")));
  String line = null;
  while((line=bufr.readLine())!=null){
   if("over".equals(line)){
    break;
   }
   bufw.write(line);
   bufw.newLine();
   bufw.flush();
  }
 }
}