From 95cb6502618e2a2fce4a419c1ec63d07e6d37685 Mon Sep 17 00:00:00 2001
From: David Craine <dcraine@users.sourceforge.net>
Date: Wed, 28 Aug 2002 15:38:14 +0000
Subject: [PATCH] Cleaned up the cancel process

git-svn-id: https://pmd.svn.sourceforge.net/svnroot/pmd/trunk@808 51baf565-9d33-0410-a72c-fc3788e3496d
---
 pmd/src/net/sourceforge/pmd/cpd/CPD.java |  1 +
 pmd/src/net/sourceforge/pmd/cpd/GST.java | 38 ++++++++++++++----------
 2 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/pmd/src/net/sourceforge/pmd/cpd/CPD.java b/pmd/src/net/sourceforge/pmd/cpd/CPD.java
index c5a3031e57..fa9675ab32 100644
--- a/pmd/src/net/sourceforge/pmd/cpd/CPD.java
+++ b/pmd/src/net/sourceforge/pmd/cpd/CPD.java
@@ -73,6 +73,7 @@ public class CPD {
         if (!listener.update("Starting to process " + tokenSets.size() + " files")) return;
         GST gst = new GST(tokenSets, minimumTileSize);
         results = gst.crunch(listener);
+        if (results == null) results = new Results();  //just ot make sure we don't pass back a null Results
     }
 
     public Results getResults() {
diff --git a/pmd/src/net/sourceforge/pmd/cpd/GST.java b/pmd/src/net/sourceforge/pmd/cpd/GST.java
index ebebfda76e..76bdd06b9f 100644
--- a/pmd/src/net/sourceforge/pmd/cpd/GST.java
+++ b/pmd/src/net/sourceforge/pmd/cpd/GST.java
@@ -1,7 +1,7 @@
 /*
- * User: tom
- * Date: Jul 30, 2002
- * Time: 10:55:08 AM
+* User: tom
+* Date: Jul 30, 2002
+* Time: 10:55:08 AM
  */
 package net.sourceforge.pmd.cpd;
 
@@ -15,20 +15,23 @@ public class GST {
     private int minimumTileSize;
     private TokenSets tokenSets;
 
+    class CancelledException extends Exception {
+    }
+
     public GST(TokenSets tokenSets, int minimumTileSize) {
         this.minimumTileSize = minimumTileSize;
         this.tokenSets = tokenSets;
     }
 
-	public Results crunch(CPDListener listener) {
+    public Results crunch(CPDListener listener) {
         Results results = new Results();
         Occurrences occ =new Occurrences(tokenSets, listener);
 
         while (!occ.isEmpty()) {
-			if (!listener.update("Tiles left to be crunched " + occ.size())) return null;
+            if (!listener.update("Tiles left to be crunched " + occ.size())) return null;
 
             // add any tiles over the minimum size to the results
-			if (!listener.update("Adding large tiles to results")) return null;
+            if (!listener.update("Adding large tiles to results")) return null;
             for (Iterator i = occ.getTiles(); i.hasNext();) {
                 Tile tile = (Tile)i.next();
                 if (tile.getTokenCount() >= minimumTileSize) {
@@ -41,23 +44,28 @@ public class GST {
             Occurrences newOcc = new Occurrences(listener);
             int tilesSoFar = 0;
             int totalTiles = occ.size();
-            for (Iterator i = occ.getTiles(); i.hasNext();) {
-                tilesSoFar++;
-                Tile tile = (Tile)i.next();
-                if (!newOcc.containsAnyTokensIn(tile)) {
-                    expandTile(occ, newOcc, tile, listener, tilesSoFar, totalTiles);
+            try {
+                for (Iterator i = occ.getTiles(); i.hasNext();) {
+                    tilesSoFar++;
+                    Tile tile = (Tile)i.next();
+                    if (!newOcc.containsAnyTokensIn(tile)) {
+                        expandTile(occ, newOcc, tile, listener, tilesSoFar, totalTiles);
+                    }
                 }
             }
+            catch (CancelledException ce) {
+                return null;
+            }
             occ = newOcc;
         }
         return results;
     }
 
     public Results crunch() {
-		return crunch(new CPDNullListener());
+        return crunch(new CPDNullListener());
     }
 
-    private void expandTile(Occurrences oldOcc, Occurrences newOcc, Tile tile, CPDListener listener, int tilesSoFar, int totalTiles) {
+    private void expandTile(Occurrences oldOcc, Occurrences newOcc, Tile tile, CPDListener listener, int tilesSoFar, int totalTiles) throws CancelledException {
         for (Iterator i = oldOcc.getOccurrences(tile); i.hasNext();) {
             TokenEntry tok = (TokenEntry)i.next();
             TokenList tokenSet = tokenSets.getTokenList(tok);
@@ -68,10 +76,10 @@ public class GST {
                     Tile newTile = tile.copy();
                     newTile.add(token);
                     newOcc.addTile(newTile, tok);
-					if (!listener.addedNewTile(newTile, tilesSoFar, totalTiles)) break;
+                    if (!listener.addedNewTile(newTile, tilesSoFar, totalTiles)) throw new CancelledException();
                 }
             }
         }
         newOcc.deleteSoloTiles();
     }
-}
+}
\ No newline at end of file