diff --git a/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java b/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java
index c80280bcf1..1352b716cd 100644
--- a/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java
+++ b/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java
@@ -35,36 +35,36 @@ import org.apache.poi.util.Internal;
 @Internal
 public final class CollaboratingWorkbooksEnvironment {
 
-	public static final class WorkbookNotFoundException extends Exception {
+    public static final class WorkbookNotFoundException extends Exception {
         private static final long serialVersionUID = 8787784539811167941L;
 
         WorkbookNotFoundException(String msg) {
-			super(msg);
-		}
-	}
+            super(msg);
+        }
+    }
 
-	public static final CollaboratingWorkbooksEnvironment EMPTY = new CollaboratingWorkbooksEnvironment();
+    public static final CollaboratingWorkbooksEnvironment EMPTY = new CollaboratingWorkbooksEnvironment();
 
-	private final Map<String, WorkbookEvaluator> _evaluatorsByName;
-	private final WorkbookEvaluator[] _evaluators;
+    private final Map<String, WorkbookEvaluator> _evaluatorsByName;
+    private final WorkbookEvaluator[] _evaluators;
 
-	private boolean _unhooked;
-	private CollaboratingWorkbooksEnvironment() {
-		_evaluatorsByName = Collections.emptyMap();
-		_evaluators = new WorkbookEvaluator[0];
-	}
-	
-	public static void setup(String[] workbookNames, WorkbookEvaluator[] evaluators) {
-		int nItems = workbookNames.length;
-		if (evaluators.length != nItems) {
-			throw new IllegalArgumentException("Number of workbook names is " + nItems
-					+ " but number of evaluators is " + evaluators.length);
-		}
-		if (nItems < 1) {
-			throw new IllegalArgumentException("Must provide at least one collaborating worbook");
-		}
-		new CollaboratingWorkbooksEnvironment(workbookNames, evaluators, nItems);
-	}
+    private boolean _unhooked;
+    private CollaboratingWorkbooksEnvironment() {
+        _evaluatorsByName = Collections.emptyMap();
+        _evaluators = new WorkbookEvaluator[0];
+    }
+
+    public static void setup(String[] workbookNames, WorkbookEvaluator[] evaluators) {
+        int nItems = workbookNames.length;
+        if (evaluators.length != nItems) {
+            throw new IllegalArgumentException("Number of workbook names is " + nItems
+                    + " but number of evaluators is " + evaluators.length);
+        }
+        if (nItems < 1) {
+            throw new IllegalArgumentException("Must provide at least one collaborating worbook");
+        }
+        new CollaboratingWorkbooksEnvironment(workbookNames, evaluators, nItems);
+    }
     public static void setup(Map<String,WorkbookEvaluator> evaluatorsByName) {
         if (evaluatorsByName.size() < 1) {
             throw new IllegalArgumentException("Must provide at least one collaborating worbook");
@@ -74,28 +74,28 @@ public final class CollaboratingWorkbooksEnvironment {
         new CollaboratingWorkbooksEnvironment(evaluatorsByName, evaluators);
     }
 
-	private CollaboratingWorkbooksEnvironment(String[] workbookNames, WorkbookEvaluator[] evaluators, int nItems) {
-	    this(toUniqueMap(workbookNames, evaluators, nItems), evaluators);
-	}
-	private static Map<String, WorkbookEvaluator> toUniqueMap(String[] workbookNames, WorkbookEvaluator[] evaluators, int nItems) {
-		Map<String, WorkbookEvaluator> evaluatorsByName = new HashMap<String, WorkbookEvaluator>(nItems * 3 / 2);
-		for(int i=0; i<nItems; i++) {
-			String wbName = workbookNames[i];
-			WorkbookEvaluator wbEval = evaluators[i];
-			if (evaluatorsByName.containsKey(wbName)) {
-				throw new IllegalArgumentException("Duplicate workbook name '" + wbName + "'");
-			}
-			evaluatorsByName.put(wbName, wbEval);
-		}
-		return evaluatorsByName;
-	}
+    private CollaboratingWorkbooksEnvironment(String[] workbookNames, WorkbookEvaluator[] evaluators, int nItems) {
+        this(toUniqueMap(workbookNames, evaluators, nItems), evaluators);
+    }
+    private static Map<String, WorkbookEvaluator> toUniqueMap(String[] workbookNames, WorkbookEvaluator[] evaluators, int nItems) {
+        Map<String, WorkbookEvaluator> evaluatorsByName = new HashMap<String, WorkbookEvaluator>(nItems * 3 / 2);
+        for(int i=0; i<nItems; i++) {
+            String wbName = workbookNames[i];
+            WorkbookEvaluator wbEval = evaluators[i];
+            if (evaluatorsByName.containsKey(wbName)) {
+                throw new IllegalArgumentException("Duplicate workbook name '" + wbName + "'");
+            }
+            evaluatorsByName.put(wbName, wbEval);
+        }
+        return evaluatorsByName;
+    }
     private CollaboratingWorkbooksEnvironment(Map<String, WorkbookEvaluator> evaluatorsByName, WorkbookEvaluator[] evaluators) {
         IdentityHashMap<WorkbookEvaluator, String> uniqueEvals = new IdentityHashMap<WorkbookEvaluator, String>(evaluators.length);
         for (String wbName : evaluatorsByName.keySet()) {
             WorkbookEvaluator wbEval = evaluatorsByName.get(wbName);
             if (uniqueEvals.containsKey(wbEval)) {
-                String msg = "Attempted to register same workbook under names '"
-                    + uniqueEvals.get(wbEval) + "' and '" + wbName + "'";
+                String msg = "Attempted to register same workbook under names '" +
+                             uniqueEvals.get(wbEval) + "' and '" + wbName + "'";
                 throw new IllegalArgumentException(msg);
             }
             uniqueEvals.put(wbEval, wbName);
@@ -107,79 +107,78 @@ public final class CollaboratingWorkbooksEnvironment {
         _evaluatorsByName = evaluatorsByName;
     }
 
-	private static void hookNewEnvironment(WorkbookEvaluator[] evaluators, CollaboratingWorkbooksEnvironment env) {
+    private static void hookNewEnvironment(WorkbookEvaluator[] evaluators, CollaboratingWorkbooksEnvironment env) {
+        // All evaluators will need to share the same cache.
+        // but the cache takes an optional evaluation listener.
+        int nItems = evaluators.length;
+        IEvaluationListener evalListener = evaluators[0].getEvaluationListener();
+        // make sure that all evaluators have the same listener
+        for(int i=0; i<nItems; i++) {
+            if(evalListener != evaluators[i].getEvaluationListener()) {
+                // This would be very complex to support
+                throw new RuntimeException("Workbook evaluators must all have the same evaluation listener");
+            }
+        }
+        EvaluationCache cache = new EvaluationCache(evalListener);
 
-		// All evaluators will need to share the same cache.
-		// but the cache takes an optional evaluation listener.
-		int nItems = evaluators.length;
-		IEvaluationListener evalListener = evaluators[0].getEvaluationListener();
-		// make sure that all evaluators have the same listener
-		for(int i=0; i<nItems; i++) {
-			if(evalListener != evaluators[i].getEvaluationListener()) {
-				// This would be very complex to support
-				throw new RuntimeException("Workbook evaluators must all have the same evaluation listener");
-			}
-		}
-		EvaluationCache cache = new EvaluationCache(evalListener);
+        for(int i=0; i<nItems; i++) {
+            evaluators[i].attachToEnvironment(env, cache, i);
+        }
+    }
 
-		for(int i=0; i<nItems; i++) {
-			evaluators[i].attachToEnvironment(env, cache, i);
-		}
-	}
+    /**
+     * Completely dismantles all workbook environments that the supplied evaluators are part of
+     */
+    private void unhookOldEnvironments(WorkbookEvaluator[] evaluators) {
+        Set<CollaboratingWorkbooksEnvironment> oldEnvs = new HashSet<CollaboratingWorkbooksEnvironment>();
+        for(int i=0; i<evaluators.length; i++) {
+            oldEnvs.add(evaluators[i].getEnvironment());
+        }
+        CollaboratingWorkbooksEnvironment[] oldCWEs = new CollaboratingWorkbooksEnvironment[oldEnvs.size()];
+        oldEnvs.toArray(oldCWEs);
+        for (int i = 0; i < oldCWEs.length; i++) {
+            oldCWEs[i].unhook();
+        }
+    }
 
-	/**
-	 * Completely dismantles all workbook environments that the supplied evaluators are part of
-	 */
-	private void unhookOldEnvironments(WorkbookEvaluator[] evaluators) {
-		Set<CollaboratingWorkbooksEnvironment> oldEnvs = new HashSet<CollaboratingWorkbooksEnvironment>();
-		for(int i=0; i<evaluators.length; i++) {
-			oldEnvs.add(evaluators[i].getEnvironment());
-		}
-		CollaboratingWorkbooksEnvironment[] oldCWEs = new CollaboratingWorkbooksEnvironment[oldEnvs.size()];
-		oldEnvs.toArray(oldCWEs);
-		for (int i = 0; i < oldCWEs.length; i++) {
-			oldCWEs[i].unhook();
-		}
-	}
+    /**
+     * Tell all contained evaluators that this environment should be discarded
+     */
+    private void unhook() {
+        if (_evaluators.length < 1) {
+            // Never dismantle the EMPTY environment
+            return;
+        }
+        for (int i = 0; i < _evaluators.length; i++) {
+            _evaluators[i].detachFromEnvironment();
+        }
+        _unhooked = true;
+    }
 
-	/**
-	 * Tell all contained evaluators that this environment should be discarded
-	 */
-	private void unhook() {
-		if (_evaluators.length < 1) {
-			// Never dismantle the EMPTY environment
-			return;
-		}
-		for (int i = 0; i < _evaluators.length; i++) {
-			_evaluators[i].detachFromEnvironment();
-		}
-		_unhooked = true;
-	}
-
-	public WorkbookEvaluator getWorkbookEvaluator(String workbookName) throws WorkbookNotFoundException {
-		if (_unhooked) {
-			throw new IllegalStateException("This environment has been unhooked");
-		}
-		WorkbookEvaluator result = _evaluatorsByName.get(workbookName);
-		if (result == null) {
-			StringBuffer sb = new StringBuffer(256);
-			sb.append("Could not resolve external workbook name '").append(workbookName).append("'.");
-			if (_evaluators.length < 1) {
-				sb.append(" Workbook environment has not been set up.");
-			} else {
-				sb.append(" The following workbook names are valid: (");
-				Iterator<String> i = _evaluatorsByName.keySet().iterator();
-				int count=0;
-				while(i.hasNext()) {
-					if (count++>0) {
-						sb.append(", ");
-					}
-					sb.append("'").append(i.next()).append("'");
-				}
-				sb.append(")");
-			}
-			throw new WorkbookNotFoundException(sb.toString());
-		}
-		return result;
-	}
+    public WorkbookEvaluator getWorkbookEvaluator(String workbookName) throws WorkbookNotFoundException {
+        if (_unhooked) {
+            throw new IllegalStateException("This environment has been unhooked");
+        }
+        WorkbookEvaluator result = _evaluatorsByName.get(workbookName);
+        if (result == null) {
+            StringBuffer sb = new StringBuffer(256);
+            sb.append("Could not resolve external workbook name '").append(workbookName).append("'.");
+            if (_evaluators.length < 1) {
+                sb.append(" Workbook environment has not been set up.");
+            } else {
+                sb.append(" The following workbook names are valid: (");
+                Iterator<String> i = _evaluatorsByName.keySet().iterator();
+                int count=0;
+                while(i.hasNext()) {
+                    if (count++>0) {
+                        sb.append(", ");
+                    }
+                    sb.append("'").append(i.next()).append("'");
+                }
+                sb.append(")");
+            }
+            throw new WorkbookNotFoundException(sb.toString());
+        }
+        return result;
+    }
 }