Changeset 7734 for trunk/gsdl/src/java

Timestamp:

2004-07-13T10:57:05+12:00 (20 years ago)

Author:

kjdon

Message:

commiting John T's changes (c/- DL Consulting) to stop phind hanging the browser if the gsdl server goes boom

File:

• trunk/gsdl/src/java/org/nzdl/gsdl/Phind/Phind.java (modified) (6 diffs)

trunk/gsdl/src/java/org/nzdl/gsdl/Phind/Phind.java

@@ -90 +90 @@
 
 import java.net.Socket;
+import java.net.SocketTimeoutException;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
@@ -187 +188 @@
     //    ignored.
 
-  
+    /** We're adding a timeout to the loop used to read the result from the
+     *  server - partially because of the 'fails to return anything' death
+     *  spiral - but also because its a good idea anyway. Why DataInputStream
+     *  doesn't have a TimeOutException, given its most often used to get data
+     *  from a URL, I don't know. Lets default it to 60 seconds.
+     *  DLConsulting 12-07-2004
+     */
+    private int timeout = 60;
+
     public String getAppletInfo() {
     return "Phind by Gordon Paynter ([email protected]). Copyright 1997-2000.";
@@ -457 +466 @@
     // Send the query to the phindcgi program 
     System.out.println("sending query: " + query);
+    /** Start timeout counter.
+     *  DLConsulting 12-07-2004
+     */
+    int time = 0;
     try {
         URL phindcgi = new URL(query);
@@ -467 +480 @@
         if (availableBytes == 0) {
             // if i had threads i'd do a wait here for 1 second
+            /** Ah-ha but we do have threads here - at least one thread 
+             *  anyway! Note that we want to prevent interrupted 
+             *  exceptions flinging us out of the read loop.
+             *  We also check that the time count hasn't reached out
+             *  timeout threshold yet. If so, make use of the nifty
+             *  execption handling.
+             *  DLConsulting 12-07-2004
+             *  Start...
+             */
+            if(time >= timeout) {
+            throw new SocketTimeoutException(
+                "No data recieved in " + time + 
+                " seconds. Connection timed-out.");
+            }
+            try {
+            Thread.sleep(1000);
+            }
+            catch(InterruptedException exception) {
+            System.err.println("Unexpected InterruptedException. Non-fatal.");
+            exception.printStackTrace();
+            }
+            time++;
+            /** ...End */
         } else {
             buffer = new byte[availableBytes];
@@ -685 +721 @@
     // expansion_bg = parameterValue("expansion_bg", Color.white);
     // document_bg = parameterValue("document_bg", Color.white);
+
+    /** How long should the read loop wait before timing out?
+     *  DLConsulting 12-07-2004
+     */
+    timeout = parameterValue("timeout", 60);
     }
 
@@ -917 +958 @@
 
 }
+