谁能给我一个PipedInputStream and PipedOutputStream 怎么用的例子，我想用数据库image字段对另一个imaeagezi字段

Question

这是Sun的一个例子，看看吧。
RhymingWords.java:import java.io.*;class RhymingWords {
    public static void main(String[] args) {        try {
            DataInputStream words = new DataInputStream(new FileInputStream("words.txt"));                // do the reversing and sorting
            InputStream rhymedWords = reverse(sort(reverse(words)));                // write new list to standard out
            DataInputStream dis = new DataInputStream(rhymedWords);
            String input;            while ((input = dis.readLine()) != null) {
                System.out.println(input);
            }
            dis.close();        } catch (Exception e) {
            System.out.println("RhymingWords: " + e);
        }
    }    public static InputStream reverse(InputStream source) {
        PipedOutputStream pos = null;
        PipedInputStream pis = null;        try {
            DataInputStream dis = new DataInputStream(source);            pos = new PipedOutputStream();
            pis = new PipedInputStream(pos);
            PrintStream ps = new PrintStream(pos);            new WriteReversedThread(ps, dis).start();        } catch (Exception e) {
            System.out.println("RhymingWords reverse: " + e);
        }
        return pis;
    }    public static InputStream sort(InputStream source) {
        PipedOutputStream pos = null;
        PipedInputStream pis = null;        try {
            DataInputStream dis = new DataInputStream(source);            pos = new PipedOutputStream();
            pis = new PipedInputStream(pos);
            PrintStream ps = new PrintStream(pos);            new SortThread(ps, dis).start();        } catch (Exception e) {
            System.out.println("RhymingWords sort: " + e);
        }
        return pis;
    }
}

Answer 1

SortThread.java:import java.io.*;class SortThread extends Thread {
    PrintStream ps;
    DataInputStream dis;    SortThread(PrintStream ps, DataInputStream dis) {
        this.ps = ps;
        this.dis = dis;
    }    public void run() {
         int MAXWORDS = 50;        if (ps != null && dis != null) {
            try {
                String[] listOfWords = new String[MAXWORDS];
                int numwords = 0, i = 0;
 
                while ((listOfWords[numwords] = dis.readLine()) != null) {
                    numwords++;
                }
                quicksort(listOfWords, 0, numwords-1);
                for (i = 0; i < numwords; i++) {
                    ps.println(listOfWords[i]);
                }
                ps.close();
            } catch (IOException e) {
                System.out.println("WriteReversedThread run: " + e);
            }
        }
    }    protected void finalize() {
        try {
            if (ps != null) {
                ps.close();
                ps = null;
            }
            if (dis != null) {
                dis.close();
                dis = null;
            }
        } catch (IOException e) {
            System.out.println("WriteReversedThread finalize: " + e);
        }
    }    private static void quicksort(String[] a, int lo0, int hi0) {
        int lo = lo0;
        int hi = hi0;
        if (lo >= hi) {
            return;
        }
        String mid = a[(lo + hi) / 2];
        while (lo < hi) {
            while (lo<hi && a[lo].compareTo(mid) < 0) {
                lo++;
            }
            while (lo<hi && a[hi].compareTo(mid) > 0) {
                hi--;
            }
            if (lo < hi) {
                String T = a[lo];
                a[lo] = a[hi];
                a[hi] = T;
            }
        }
        if (hi < lo) {
            int T = hi;
            hi = lo;
            lo = T;
        }
        quicksort(a, lo0, lo);
        quicksort(a, lo == lo0 ? lo+1 : lo, hi0);
    }
}

Answer 2

WriteReversedThread.java:import java.io.*;class WriteReversedThread extends Thread {
    PrintStream ps;
    DataInputStream dis;    WriteReversedThread(PrintStream ps, DataInputStream dis) {
        this.ps = ps;
        this.dis = dis;
    }    public void run() {
        if (ps != null && dis != null) {
            try {
                String input;
                while ((input = dis.readLine()) != null) {
                    ps.println(reverseIt(input));
                    ps.flush();
                }
                ps.close();
            } catch (IOException e) {
                System.out.println("WriteReversedThread run: " + e);
            }
        }
    }    protected void finalize() {
        try {
            if (ps != null) {
                ps.close();
                ps = null;
            }
            if (dis != null) {
                dis.close();
                dis = null;
            }
        } catch (IOException e) {
            System.out.println("WriteReversedThread finalize: " + e);
        }
    }    private String reverseIt(String source) {
        int i, len = source.length();
        StringBuffer dest = new StringBuffer(len);        for (i = (len - 1); i >= 0; i--) {
            dest.append(source.charAt(i));
        }
        return dest.toString();
    }
}
words.txt:
anatomy
animation
applet
application
argument
bolts
class
communicate
component
container
development
environment
exception
graphics
image
input
integrate
interface
Java
language
native
network
nuts
object
output
primer
program
security
stream
string
threads
tools
user