Java/Threads/File IO Threads
BufferedWriter and threads
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.PipedReader;
import java.io.PipedWriter;
import java.io.Reader;
import java.io.Writer;
public class PipedCharacters extends Object {
public static void writeStuff(Writer rawOut) {
try {
BufferedWriter out = new BufferedWriter(rawOut);
String[][] line = { { "Java", "Source", "and", "Support." }};
for (int i = 0; i < line.length; i++) {
String[] word = line[i];
for (int j = 0; j < word.length; j++) {
out.write(word[j]);
}
out.newLine();
}
out.flush();
out.close();
} catch (IOException x) {
x.printStackTrace();
}
}
public static void readStuff(Reader rawIn) {
try {
BufferedReader in = new BufferedReader(rawIn);
String line;
while ((line = in.readLine()) != null) {
System.out.println("read line: " + line);
}
System.out.println("Read all data from the pipe");
} catch (IOException x) {
x.printStackTrace();
}
}
public static void main(String[] args) {
try {
final PipedWriter out = new PipedWriter();
final PipedReader in = new PipedReader(out);
Runnable runA = new Runnable() {
public void run() {
writeStuff(out);
}
};
Thread threadA = new Thread(runA, "threadA");
threadA.start();
Runnable runB = new Runnable() {
public void run() {
readStuff(in);
}
};
Thread threadB = new Thread(runB, "threadB");
threadB.start();
} catch (IOException x) {
x.printStackTrace();
}
}
}
Output stream and threads
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
public class PipedBytes extends Object {
public static void writeStuff(OutputStream rawOut) {
try {
DataOutputStream out = new DataOutputStream(
new BufferedOutputStream(rawOut));
int[] data = { 82, 105, 99, 104, 97, 114, 100, 32, 72, 121, 100,
101 };
for (int i = 0; i < data.length; i++) {
out.writeInt(data[i]);
}
out.flush();
out.close();
} catch (IOException x) {
x.printStackTrace();
}
}
public static void readStuff(InputStream rawIn) {
try {
DataInputStream in = new DataInputStream(new BufferedInputStream(
rawIn));
boolean eof = false;
while (!eof) {
try {
int i = in.readInt();
System.out.println("just read: " + i);
} catch (EOFException eofx) {
eof = true;
}
}
System.out.println("Read all data from the pipe");
} catch (IOException x) {
x.printStackTrace();
}
}
public static void main(String[] args) {
try {
final PipedOutputStream out = new PipedOutputStream();
final PipedInputStream in = new PipedInputStream(out);
Runnable runA = new Runnable() {
public void run() {
writeStuff(out);
}
};
Thread threadA = new Thread(runA, "threadA");
threadA.start();
Runnable runB = new Runnable() {
public void run() {
readStuff(in);
}
};
Thread threadB = new Thread(runB, "threadB");
threadB.start();
} catch (IOException x) {
x.printStackTrace();
}
}
}
Using pipes for inter-thread I/O
// : c13:PipedIO.java
// Using pipes for inter-thread I/O
// From "Thinking in Java, 3rd ed." (c) Bruce Eckel 2002
// www.BruceEckel.ru. See copyright notice in CopyRight.txt.
import java.util.Timer;
import java.util.TimerTask;
import java.io.IOException;
import java.io.PipedReader;
import java.io.PipedWriter;
import java.util.Random;
class Sender extends Thread {
private Random rand = new Random();
private PipedWriter out = new PipedWriter();
public PipedWriter getPipedWriter() {
return out;
}
public void run() {
while (true) {
for (char c = "A"; c <= "z"; c++) {
try {
out.write(c);
sleep(rand.nextInt(500));
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
}
}
class Receiver extends Thread {
private PipedReader in;
public Receiver(Sender sender) throws IOException {
in = new PipedReader(sender.getPipedWriter());
}
public void run() {
try {
while (true) {
// Blocks until characters are there:
System.out.println("Read: " + (char) in.read());
}
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}
public class PipedIO {
public static void main(String[] args) throws Exception {
Sender sender = new Sender();
Receiver receiver = new Receiver(sender);
sender.start();
receiver.start();
new Timeout(4000, "Terminated");
}
} ///:~
class Timeout extends Timer {
public Timeout(int delay, final String msg) {
super(true); // Daemon thread
schedule(new TimerTask() {
public void run() {
System.out.println(msg);
System.exit(0);
}
}, delay);
}
} ///:~