add the Java Client from M0AZM

[spider.git] / SpiderConsole / src / PipedOutputMUX.java

diff --git a/SpiderConsole/src/PipedOutputMUX.java b/SpiderConsole/src/PipedOutputMUX.java
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+++ b/SpiderConsole/src/PipedOutputMUX.java
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+/**
+ * OutputStreamMultiplexor 
+ * Takes one output stream and sends it to multiple output streams.
+ * @author Ian Norton
+ * @version 1.0 - 20010418.
+ *
+ * Copyright (C) 2001 Ian Norton.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public Licence as published by
+ * the Free Software Foundation; either version 2 of the Licence, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public Licence for more details.
+ *
+ * You should have received a copy of the GNU General Public Licence
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Contacting the author :
+ * Ian Norton
+ * i.norton@lancaster.ac.uk
+ * http://www.lancs.ac.uk/~norton/
+ **/
+
+import java.io.* ;
+import java.util.Vector ;
+import java.util.Enumeration ;
+import java.util.Calendar ;
+
+class PipedOutputMUX implements Runnable
+    {
+    public static final boolean DEBUG = false ;
+    public static final String encoding = "latin1"; // "ISO8859_1";
+    
+    private PipedInputStream pin ;
+    private Vector streams ;
+
+    private Thread t ;
+    
+    /**
+     * PipedOutputMUX initialiser
+     * @param PipedOutputStream i - Source stream
+     **/
+    public PipedOutputMUX(PipedInputStream i)
+        {
+        pin = i ;
+         
+        // Streams Vector holds all the OutputStreams we know about.
+        streams = new Vector() ;
+
+        // Initialise and start the thread.
+        t = new Thread(this, "OutputMultiplexor") ;
+        t.start() ;
+        }
+
+    /**
+     * addOutputStream
+     * @param PipedOutputStream po - add a stream to send output to.
+     **/
+    public void addOutputStream(PipedOutputStream po)
+        {
+        // Add the supplied stream to the vector of streams.
+        streams.addElement(po) ;
+        }
+
+    /**
+     * run - Thread run method.
+     **/
+    public void run()
+        {
+        // Loop continually reading the input stream.
+        while(true)
+            {
+            try
+                {
+                byte[] b = new byte[16];
+
+                // Read a line and see if it has any data in it.
+                int n = 0;
+
+                // Trying to read
+                while(pin.available() > 0)
+                    {
+                    int rdb = pin.available() ;
+                    if(rdb > 16) rdb = 16 ;
+                    n = pin.read(b, 0, rdb);
+
+                    if(n > 0)
+                        {
+                        // Convert the output to a string and send it.
+                        String output = new String(b, 0, n, encoding) ;
+                        if(DEBUG) System.out.println(output) ;
+                        send(output) ;
+                        }
+                    }
+                }
+            catch(IOException ex)
+                {
+                System.out.println("PipedOutputMUX: IOException trying to read.") ;
+                System.exit(1) ;
+                }
+            } // End of loop
+        } // End of run()
+
+    /**
+     * send
+     * @param String s - string to send to all streams.
+     **/
+    private void send(String s)
+        {
+        // Calendar cal = Calendar.getInstance() ;
+        // if(DEBUG) System.out.println("PipedOutputMUX: " + cal.getTime() + " Send called with :" + s) ;
+
+        // If we have no streams, then we can't do anything.
+        if(streams.size() == 0) return ;
+        
+        // Create Enumeration object to enumerate with :-)
+        Enumeration e = streams.elements() ;
+
+        // Go through the enumeration and send the string to each stream.
+        while(e.hasMoreElements())
+            {
+            PipedOutputStream os = (PipedOutputStream)e.nextElement() ;
+
+            try
+                {
+                // Write the data to the stream.
+                for(int i=0;i<s.length();i++)
+                    {
+                    os.write(s.charAt(i)) ;
+                    os.flush() ;
+                    }
+                }
+            catch(IOException ex)
+                {
+                // If we get an IO exception, then the other end of the pipe
+                // has been closed.  We need to remove this stream.
+                streams.removeElement(os) ;
+                System.out.println("IOException - stream removed.") ;
+                }
+            }
+        }
+
+    } // End of class.