PipedInputStream

PipedInputStream
PipedInputStream Sınıfı
java.lang.Object
java.io.InputStream
java.io.PipedInputStream
Kılgıladığı Arayüzler:
Closeable, AutoCloseable
Bildirimi:
public class PipedInputStream
extends InputStream
Bir thread ile buffer’a veri girişi başka bir thred ile buffer’dan veri çıkışı yapar. Bir su deposunun bir
vanasından su girişi, başka bir vanasından sı çıkışı olmasına benzetilebilir.
import java.io.*;
public class Demo {
public static void main(String args[]) throws Exception {
byte[] b = {10, 20, 30, 40, 50};
PipedOutputStream poStream = new PipedOutputStream();
PipedInputStream piStream = new PipedInputStream();
//girişçıkışa bağlanıyor
piStream.connect(poStream);
//array'in bileşenleri yazdırılıyor
poStream.write(b, 0, 5);
//PipedInputStream akımı okunuyor ve ekrana yazdırılıyor
for (int i = 0; i < b.length; i++) {
System.out.println(piStream.read());
}
// giriş akımı kapatılıyor
poStream.close();
// çıkış akımı kapatılıyor
piStream.close();
}
}
/**
10
20
30
40
50
*/
How can we use the pipedout- and pipedinputstream. The basic use lies in
combination with thread. For example we have a reader thread, a decode thread
and a writer thread. The first one reads the information and sends it to an
outputstream, this is picked up by the
decode thread to decode the stream and send it to it output, and finally this is
being picked up by the writer thread to write it to its output.
Graphically this is what is happening:
FileInputStream readIn = new FileInputStream(inputFile);
// The first pipe
PipedInputStream decodeIn = new PipedInputStream();
PipedOutputStream readOut = new PipedOutputStream(decodeIn);
// The second pipe
PipedInputStream writeIn = new PipedInputStream();
PipedOutputStream decodeOut = new PipedOutputStream(writeIn);
FileOutputStream output = new FileOutputStream(outputFile);
pipeThread reader = new pipeThread("reader", readIn, readOut);
decodeThread decode = new decodeThread("decode",decodeIn , decodeOut
, bits);
pipeThread writer = new pipeThread ("writer", writeIn, writeOut);
reader.start();
decode.start();
writer.start();
Örnek
import java.io.*;
/**
* Komut satırından klavye girişi
*/
class ReadThread extends Thread implements Runnable {
InputStream pi = null;
OutputStream po = null;
String process = null;
ReadThread( String process, InputStream pi, OutputStream po) {
this.pi = pi; this.po = po; this.process = process; }
public void run() {
int ch; byte[] buffer = new byte[512]; int bytes_read;
try {
for(;;) {
bytes_read = pi.read(buffer);
if (bytes_read == -1) { return; }
po.write(buffer, 0, bytes_read);
}
} catch (Exception e) { e.printStackTrace();
} finally { }
}
}
class SystemStream {
public static void main( String [] args) {
try {
int ch;
while (true) {
PipedInputStream writeIn = new PipedInputStream();
PipedOutputStream readOut = new PipedOutputStream( writeIn );
FileOutputStream writeOut = new FileOutputStream("out");
ReadThread rt = new ReadThread("reader", System.in, readOut );
ReadThread wt = new ReadThread("writer", writeIn, System.out );
rt.start();
wt.start();
}
} catch (Exception e) {
e.printStackTrace();
}
}
}