java学习之路----IO----内存操作流和管道流

我们的流操作除了在文件上操作，还可以在内存中操作

                    用到的类
                    ByteArrayInputStream 主要完成把文件写入内存

                    ByteArrayOutputStream 主要将内存中内容输出

利用内存流来完成一个字符串大小写的转换

          public class ByteArrayDemo {

           public static void main(String[]
args) throws Exception{

              String str= "HELLO WORLD";

              

              ByteArrayInputStream in= null;//内存输入流

              

              ByteArrayOutputStream out= null;//内存输出流

              

              in= new ByteArrayInputStream(str.getBytes());//向内存中输入内容

              

              out= new ByteArrayOutputStream();//准备输出

              

               int temp=0;

              

               while((temp=in.read())!=-1){

                    char c=(char )temp;

                   out.write(Character. toLowerCase(c));

              }

              String newStr=out.toString();

              in.close();

              out.close();

              System. out.println(newStr);

          }

}

结果：

[align=left]hello world[/align]
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[align=left]内存流的作用一般是用来写临时文件的。[/align]
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管道流的作用是用来进行两个线程之间的通信

          管道流分为输出流和输入流

                    如果要进行线程之间的通信，即必须要把输入流接到输出流上

     下面来验证一下管道流

class Send implements Runnable{

     private PipedOutputStream pip= null;//管道输出流

     

     

     public Send()
{

           this.pip = new PipedOutputStream();

     }

     public void run()
{

     String str= "hello world";

     

           try {

               this.pip .write(str.getBytes());//输出信息

          } catch (IOException
e) {

               // TODO Auto-generated
catch block

              e.printStackTrace();

          }

          

           try {

               this.pip .close();

          } catch (IOException
e) {

               // TODO Auto-generated
catch block

              e.printStackTrace();

          }

          

     }

     

     public PipedOutputStream
getpip(){

           return pip ;

     }

}

class  Receive implements Runnable{

     PipedInputStream p= null;

     

     public Receive()
{

           this.p = new PipedInputStream();

     }

     public void run()
{

           byte b[]=new byte[1024];

           int len=0;

          

           try {

          len=  this.p .read(b);

          } catch (IOException
e) {

               // TODO Auto-generated
catch block

              e.printStackTrace();

          }

           try {

               p.close();

          } catch (IOException
e) {

               // TODO Auto-generated
catch block

              e.printStackTrace();

          }

          System. out.println("接收的内容是：" +new String(b,0,len));

     }

     

     public PipedInputStream
getP(){

           return p ;

     }

     

}

public class PipDemo
{

           public static void main(String[]
args) {

              Send s= new Send();

              

              Receive r= new Receive();

              

          

              

               try {

                   s.getpip().connect(r.getP());      //接通管道

              } catch (IOException
e) {

                    // TODO Auto-generated
catch block

                   e.printStackTrace();

              }

              

               new Thread(s).start();

               new Thread(r).start();

          }

}

结果：

[align=left]接收的内容是：hello world[/align]
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