Refactor ProxyIterators to AbstractDecorators

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@131313 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/collections/iterators/AbstractIteratorDecorator.java

@@ -0,0 +1,115 @@
+/*
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/AbstractIteratorDecorator.java,v 1.1 2003/11/02 16:29:12 scolebourne Exp $
+ * ====================================================================
+ *
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999-2003 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowledgement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgement may appear in the software itself,
+ *    if and wherever such third-party acknowledgements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Commons", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ */
+package org.apache.commons.collections.iterators;
+
+import java.util.Iterator;
+
+/** 
+ * Provides basic behaviour for decorating an iterator with extra functionality.
+ * <p>
+ * All methods are forwarded to the decorated iterator.
+ *
+ * @since Commons Collections 3.0
+ * @version $Revision: 1.1 $ $Date: 2003/11/02 16:29:12 $
+ * 
+ * @author James Strachan
+ * @author Stephen Colebourne
+ */
+public class AbstractIteratorDecorator implements Iterator {
+
+    /** The iterator being decorated */
+    private Iterator iterator;
+
+    //-----------------------------------------------------------------------
+    /**
+     * Constructor that decorates the specified iterator.
+     *
+     * @param iterator  the iterator to decorate, must not be null
+     * @throws IllegalArgumentException if the collection is null
+     */
+    public AbstractIteratorDecorator(Iterator iterator) {
+        super();
+        if (iterator == null) {
+            throw new IllegalArgumentException("Iterator must not be null");
+        }
+        this.iterator = iterator;
+    }
+
+    /**
+     * Gets the iterator being decorated.
+     * 
+     * @return the decorated iterator
+     */
+    protected Iterator getIterator() {
+        return iterator;
+    }
+
+    //-----------------------------------------------------------------------
+    public boolean hasNext() {
+        return iterator.hasNext();
+    }
+
+    public Object next() {
+        return iterator.next();
+    }
+
+    public void remove() {
+        iterator.remove();
+    }
+
+}

src/java/org/apache/commons/collections/iterators/AbstractListIteratorDecorator.java

@@ -0,0 +1,138 @@
+/*
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/AbstractListIteratorDecorator.java,v 1.1 2003/11/02 16:29:12 scolebourne Exp $
+ * ====================================================================
+ *
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999-2003 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowledgement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgement may appear in the software itself,
+ *    if and wherever such third-party acknowledgements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Commons", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ */
+package org.apache.commons.collections.iterators;
+
+import java.util.ListIterator;
+
+/**
+ * Provides basic behaviour for decorating a list iterator with extra functionality.
+ * <p>
+ * All methods are forwarded to the decorated list iterator.
+ *
+ * @since Commons Collections 3.0
+ * @version $Revision: 1.1 $ $Date: 2003/11/02 16:29:12 $
+ * 
+ * @author Rodney Waldhoff
+ * @author Stephen Colebourne
+ */
+public class AbstractListIteratorDecorator implements ListIterator {
+
+    /** The iterator being decorated */
+    private ListIterator iterator;
+
+    //-----------------------------------------------------------------------
+    /**
+     * Constructor that decorates the specified iterator.
+     *
+     * @param iterator  the iterator to decorate, must not be null
+     * @throws IllegalArgumentException if the collection is null
+     */
+    public AbstractListIteratorDecorator(ListIterator iterator) {
+        super();
+        if (iterator == null) {
+            throw new IllegalArgumentException("ListIterator must not be null");
+        }
+        this.iterator = iterator;
+    }
+
+    /**
+     * Gets the iterator being decorated.
+     * 
+     * @return the decorated iterator
+     */
+    protected ListIterator getListIterator() {
+        return iterator;
+    }
+
+    //-----------------------------------------------------------------------
+    public boolean hasNext() {
+        return iterator.hasNext();
+    }
+
+    public Object next() {
+        return iterator.next();
+    }
+
+    public int nextIndex() {
+        return iterator.nextIndex();
+    }
+
+    public boolean hasPrevious() {
+        return iterator.hasPrevious();
+    }
+
+    public Object previous() {
+        return iterator.previous();
+    }
+
+    public int previousIndex() {
+        return iterator.previousIndex();
+    }
+
+    public void remove() {
+        iterator.remove();
+    }
+
+    public void set(Object obj) {
+        iterator.set(obj);
+    }
+
+    public void add(Object obj) {
+        iterator.add(obj);
+    }
+}

src/java/org/apache/commons/collections/iterators/AbstractMapIteratorDecorator.java

@@ -0,0 +1,130 @@
+/*
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/AbstractMapIteratorDecorator.java,v 1.1 2003/11/02 16:29:12 scolebourne Exp $
+ * ====================================================================
+ *
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999-2003 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowledgement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgement may appear in the software itself,
+ *    if and wherever such third-party acknowledgements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Commons", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ */
+package org.apache.commons.collections.iterators;
+
+import java.util.Map;
+
+/**
+ * Provides basic behaviour for decorating a map iterator with extra functionality.
+ * <p>
+ * All methods are forwarded to the decorated map iterator.
+ *
+ * @since Commons Collections 3.0
+ * @version $Revision: 1.1 $ $Date: 2003/11/02 16:29:12 $
+ * 
+ * @author Stephen Colebourne
+ */
+public class AbstractMapIteratorDecorator implements MapIterator {
+
+    /** The iterator being decorated */
+    private MapIterator iterator;
+
+    //-----------------------------------------------------------------------
+    /**
+     * Constructor that decorates the specified iterator.
+     *
+     * @param iterator  the iterator to decorate, must not be null
+     * @throws IllegalArgumentException if the collection is null
+     */
+    public AbstractMapIteratorDecorator(MapIterator iterator) {
+        super();
+        if (iterator == null) {
+            throw new IllegalArgumentException("MapIterator must not be null");
+        }
+        this.iterator = iterator;
+    }
+
+    /**
+     * Gets the iterator being decorated.
+     * 
+     * @return the decorated iterator
+     */
+    protected MapIterator getMapIterator() {
+        return iterator;
+    }
+
+    //-----------------------------------------------------------------------
+    public boolean hasNext() {
+        return iterator.hasNext();
+    }
+
+    public Object next() {
+        return iterator.next();
+    }
+
+    public void remove() {
+        iterator.remove();
+    }
+    
+    public Object getKey() {
+        return iterator.getKey();
+    }
+
+    public Object getValue() {
+        return iterator.getValue();
+    }
+
+    public Object setValue(Object obj) {
+        return iterator.setValue(obj);
+    }
+
+    public Map.Entry asMapEntry() {
+        return iterator.asMapEntry();
+    }
+
+}

src/java/org/apache/commons/collections/iterators/FilterIterator.java

@@ -1,5 +1,5 @@
 /*
- * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/FilterIterator.java,v 1.5 2003/09/29 22:02:33 scolebourne Exp $
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/FilterIterator.java,v 1.6 2003/11/02 16:29:12 scolebourne Exp $
  * ====================================================================
  *
  * The Apache Software License, Version 1.1
@@ -59,33 +59,33 @@ package org.apache.commons.collections.iterators;
 
 import java.util.Iterator;
 import java.util.NoSuchElementException;
+
 import org.apache.commons.collections.Predicate;
 
 /** 
- * A Proxy {@link Iterator Iterator} which takes a {@link Predicate Predicate} instance to filter
+ * Decorates an iterator such that only elements matching a predicate filter
- * out objects from an underlying {@link Iterator Iterator} instance.
+ * are returned.
- * Only objects for which the
- * specified <code>Predicate</code> evaluates to <code>true</code> are
- * returned.
  *
  * @since Commons Collections 1.0
- * @version $Revision: 1.5 $ $Date: 2003/09/29 22:02:33 $
+ * @version $Revision: 1.6 $ $Date: 2003/11/02 16:29:12 $
  * 
- * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
+ * @author James Strachan
  * @author Jan Sorensen
  * @author Ralph Wagner
+ * @author Stephen Colebourne
  */
-public class FilterIterator extends ProxyIterator {
+public class FilterIterator implements Iterator {
 
-    /** Holds value of property predicate. */
+    /** The iterator being used */
+    private Iterator iterator;
+    /** The predicate being used */
     private Predicate predicate;
-
+    /** The next object in the iteration */
     private Object nextObject;
+    /** Whether the next object has been calculated yet */
     private boolean nextObjectSet = false;
 
-    
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
-
     /**
      * Constructs a new <code>FilterIterator</code> that will not function
      * until {@link #setIterator(Iterator) setIterator} is invoked.
@@ -101,7 +101,8 @@ public class FilterIterator extends ProxyIterator {
      * @param iterator  the iterator to use
      */
     public FilterIterator(Iterator iterator) {
-        super(iterator);
+        super();
+        this.iterator = iterator;
     }
 
     /**
@@ -112,13 +113,12 @@ public class FilterIterator extends ProxyIterator {
      * @param predicate  the predicate to use
      */
     public FilterIterator(Iterator iterator, Predicate predicate) {
-        super(iterator);
+        super();
+        this.iterator = iterator;
         this.predicate = predicate;
     }
 
-    // Iterator interface
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
-    
     /** 
      * Returns true if the underlying iterator contains an object that 
      * matches the predicate.
@@ -126,7 +126,7 @@ public class FilterIterator extends ProxyIterator {
      * @return true if there is another object that matches the predicate 
      */
     public boolean hasNext() {
-        if ( nextObjectSet ) {
+        if (nextObjectSet) {
             return true;
         } else {
             return setNextObject();
@@ -141,7 +141,7 @@ public class FilterIterator extends ProxyIterator {
      *  match the predicate 
      */
     public Object next() {
-        if ( !nextObjectSet ) {
+        if (!nextObjectSet) {
             if (!setNextObject()) {
                 throw new NoSuchElementException();
             }
@@ -165,35 +165,57 @@ public class FilterIterator extends ProxyIterator {
         if (nextObjectSet) {
             throw new IllegalStateException("remove() cannot be called");
         }
-        getIterator().remove();
+        iterator.remove();
     }
 
+    //-----------------------------------------------------------------------
+    /** 
+     * Gets the iterator this iterator is using.
+     * 
+     * @return the iterator.
+     */
+    public Iterator getIterator() {
+        return iterator;
+    }
 
-    // Properties
+    /** 
-    //-------------------------------------------------------------------------
+     * Sets the iterator for this iterator to use.
-    /** Getter for property predicate.
+     * If iteration has started, this effectively resets the iterator.
-     * @return Value of property predicate.
+     * 
+     * @param iterator  the iterator to use
+     */
+    public void setIterator(Iterator iterator) {
+        this.iterator = iterator;
+    }
+
+    //-----------------------------------------------------------------------
+    /** 
+     * Gets the predicate this iterator is using.
+     * 
+     * @return the predicate.
      */
     public Predicate getPredicate() {
         return predicate;
     }
-    /** Setter for property predicate.
+
-     * @param predicate New value of property predicate.
+    /** 
+     * Sets the predicate this the iterator to use.
+     * 
+     * @param predicate  the transformer to use
      */
     public void setPredicate(Predicate predicate) {
         this.predicate = predicate;
     }
 
+    //-----------------------------------------------------------------------
     /**
      * Set nextObject to the next object. If there are no more 
      * objects then return false. Otherwise, return true.
      */
     private boolean setNextObject() {
-        Iterator iterator = getIterator();
+        while (iterator.hasNext()) {
-        Predicate predicate = getPredicate();
-        while ( iterator.hasNext() ) {
             Object object = iterator.next();
-            if ( predicate.evaluate( object ) ) {
+            if (predicate.evaluate(object)) {
                 nextObject = object;
                 nextObjectSet = true;
                 return true;

src/java/org/apache/commons/collections/iterators/FilterListIterator.java

@@ -1,5 +1,5 @@
 /*
- * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/FilterListIterator.java,v 1.4 2003/09/29 22:02:33 scolebourne Exp $
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/FilterListIterator.java,v 1.5 2003/11/02 16:29:12 scolebourne Exp $
  * ====================================================================
  *
  * The Apache Software License, Version 1.1
@@ -59,6 +59,7 @@ package org.apache.commons.collections.iterators;
 
 import java.util.ListIterator;
 import java.util.NoSuchElementException;
+
 import org.apache.commons.collections.Predicate;
 
 /** 
@@ -70,15 +71,48 @@ import org.apache.commons.collections.Predicate;
  * returned by the iterator.
  * 
  * @since Commons Collections 2.0
- * @version $Revision: 1.4 $ $Date: 2003/09/29 22:02:33 $
+ * @version $Revision: 1.5 $ $Date: 2003/11/02 16:29:12 $
  * 
  * @author Rodney Waldhoff
  */
-public class FilterListIterator extends ProxyListIterator {
+public class FilterListIterator implements ListIterator {
 
-    // Constructors    
+    /** The iterator being used */
-    //-------------------------------------------------------------------------
+    private ListIterator iterator;
     
+    /** The predicate being used */
+    private Predicate predicate;
+
+    /** 
+     * The value of the next (matching) object, when 
+     * {@link #nextObjectSet} is true. 
+     */
+    private Object nextObject;
+
+    /** 
+     * Whether or not the {@link #nextObject} has been set
+     * (possibly to <code>null</code>). 
+     */
+    private boolean nextObjectSet = false;   
+
+    /** 
+     * The value of the previous (matching) object, when 
+     * {@link #previousObjectSet} is true. 
+     */
+    private Object previousObject;
+
+    /** 
+     * Whether or not the {@link #previousObject} has been set
+     * (possibly to <code>null</code>). 
+     */
+    private boolean previousObjectSet = false;   
+
+    /** 
+     * The index of the element that would be returned by {@link #next}.
+     */
+    private int nextIndex = 0;
+    
+    //-----------------------------------------------------------------------
     /**
      *  Constructs a new <code>FilterListIterator</code> that will not 
      *  function until 
@@ -96,7 +130,8 @@ public class FilterListIterator extends ProxyListIterator {
      * @param iterator  the iterator to use
      */
     public FilterListIterator(ListIterator iterator ) {
-        super(iterator);
+        super();
+        this.iterator = iterator;
     }
 
     /**
@@ -106,7 +141,8 @@ public class FilterListIterator extends ProxyListIterator {
      * @param predicate  the predicate to use
      */
     public FilterListIterator(ListIterator iterator, Predicate predicate) {
-        super(iterator);
+        super();
+        this.iterator = iterator;
         this.predicate = predicate;
     }
 
@@ -123,9 +159,7 @@ public class FilterListIterator extends ProxyListIterator {
         this.predicate = predicate;
     }
 
-    // ListIterator interface
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
-
     /** Not supported. */
     public void add(Object o) {
         throw new UnsupportedOperationException("FilterListIterator.add(Object) is not supported.");
@@ -189,36 +223,52 @@ public class FilterListIterator extends ProxyListIterator {
         throw new UnsupportedOperationException("FilterListIterator.set(Object) is not supported.");
     }
 
-    // Properties
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
+    /** 
+     * Gets the iterator this iterator is using.
+     * 
+     * @return the iterator.
+     */
+    public ListIterator getListIterator() {
+        return iterator;
+    }
 
     /** 
-     * Getter for the predicate property.
+     * Sets the iterator for this iterator to use.
-     * @return value of the predicate property.
+     * If iteration has started, this effectively resets the iterator.
+     * 
+     * @param iterator  the iterator to use
+     */
+    public void setListIterator(ListIterator iterator) {
+        this.iterator = iterator;
+    }
+
+    //-----------------------------------------------------------------------
+    /** 
+     * Gets the predicate this iterator is using.
+     * 
+     * @return the predicate.
      */
     public Predicate getPredicate() {
         return predicate;
     }
+
     /** 
-     * Setter for the predicate property.
+     * Sets the predicate this the iterator to use.
-     * @param predicate new value for the predicate property.
+     * 
+     * @param predicate  the transformer to use
      */
     public void setPredicate(Predicate predicate) {
         this.predicate = predicate;
     }
 
-    // Private Methods
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
-
     private void clearNextObject() {
         nextObject = null;
         nextObjectSet = false;
     }
 
     private boolean setNextObject() {
-        ListIterator iterator = getListIterator();
-        Predicate predicate = getPredicate();
-        
         // if previousObjectSet,
         // then we've walked back one step in the 
         // underlying list (due to a hasPrevious() call)
@@ -249,9 +299,6 @@ public class FilterListIterator extends ProxyListIterator {
     }
 
     private boolean setPreviousObject() {
-        ListIterator iterator = getListIterator();
-        Predicate predicate = getPredicate();
-        
         // if nextObjectSet,
         // then we've walked back one step in the 
         // underlying list (due to a hasNext() call)
@@ -276,38 +323,4 @@ public class FilterListIterator extends ProxyListIterator {
         return false;
     }
 
-    // Attributes
-    //-------------------------------------------------------------------------
-
-    /** Holds value of property "predicate". */
-    private Predicate predicate;
-
-    /** 
-     * The value of the next (matching) object, when 
-     * {@link #nextObjectSet} is true. 
-     */
-    private Object nextObject;
-
-    /** 
-     * Whether or not the {@link #nextObject} has been set
-     * (possibly to <code>null</code>). 
-     */
-    private boolean nextObjectSet = false;   
-
-    /** 
-     * The value of the previous (matching) object, when 
-     * {@link #previousObjectSet} is true. 
-     */
-    private Object previousObject;
-
-    /** 
-     * Whether or not the {@link #previousObject} has been set
-     * (possibly to <code>null</code>). 
-     */
-    private boolean previousObjectSet = false;   
-
-    /** 
-     * The index of the element that would be returned by {@link #next}.
-     */
-    private int nextIndex = 0;
 }

src/java/org/apache/commons/collections/iterators/ProxyIterator.java

@@ -1,5 +1,5 @@
 /*
- * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/ProxyIterator.java,v 1.5 2003/09/29 22:02:33 scolebourne Exp $
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/ProxyIterator.java,v 1.6 2003/11/02 16:29:12 scolebourne Exp $
  * ====================================================================
  *
  * The Apache Software License, Version 1.1
@@ -62,11 +62,11 @@ import java.util.Iterator;
 /** 
  * A Proxy {@link Iterator Iterator} which delegates its methods to a proxy instance.
  *
- * @see ProxyListIterator
+ * @deprecated Use AbstractIteratorDecorator
  * @since Commons Collections 1.0
- * @version $Revision: 1.5 $ $Date: 2003/09/29 22:02:33 $
+ * @version $Revision: 1.6 $ $Date: 2003/11/02 16:29:12 $
  * 
- * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
+ * @author James Strachan
  */
 public class ProxyIterator implements Iterator {
     

src/java/org/apache/commons/collections/iterators/ProxyListIterator.java

@@ -1,5 +1,5 @@
 /*
- * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/ProxyListIterator.java,v 1.5 2003/09/29 22:02:33 scolebourne Exp $
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/ProxyListIterator.java,v 1.6 2003/11/02 16:29:12 scolebourne Exp $
  * ====================================================================
  *
  * The Apache Software License, Version 1.1
@@ -63,9 +63,9 @@ import java.util.ListIterator;
  * A proxy {@link ListIterator ListIterator} which delegates its
  * methods to a proxy instance.
  *
- * @see ProxyIterator
+ * @deprecated Use AbstractListIteratorDecorator
  * @since Commons Collections 2.0
- * @version $Revision: 1.5 $ $Date: 2003/09/29 22:02:33 $
+ * @version $Revision: 1.6 $ $Date: 2003/11/02 16:29:12 $
  * 
  * @author Rodney Waldhoff
  */

src/java/org/apache/commons/collections/iterators/TransformIterator.java

@@ -1,5 +1,5 @@
 /*
- * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/TransformIterator.java,v 1.5 2003/09/29 22:02:33 scolebourne Exp $
+ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/iterators/TransformIterator.java,v 1.6 2003/11/02 16:29:12 scolebourne Exp $
  * ====================================================================
  *
  * The Apache Software License, Version 1.1
@@ -58,24 +58,26 @@
 package org.apache.commons.collections.iterators;
 
 import java.util.Iterator;
+
 import org.apache.commons.collections.Transformer;
 
 /** 
- * A Proxy {@link Iterator Iterator} which uses a {@link Transformer Transformer}
+ * Decorates an iterator such that each element returned is transformed.
- * instance to transform the contents of the {@link Iterator Iterator} into 
- * some other form.
  *
  * @since Commons Collections 1.0
- * @version $Revision: 1.5 $ $Date: 2003/09/29 22:02:33 $
+ * @version $Revision: 1.6 $ $Date: 2003/11/02 16:29:12 $
  * 
- * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
+ * @author James Strachan
+ * @author Stephen Colebourne
  */
-public class TransformIterator extends ProxyIterator {
+public class TransformIterator implements Iterator {
 
-    /** Holds value of property transformer. */
+    /** The iterator being used */
+    private Iterator iterator;
+    /** The transformer being used */
     private Transformer transformer;
 
-    
+    //-----------------------------------------------------------------------
     /**
      * Constructs a new <code>TransformIterator</code> that will not function
      * until the {@link #setIterator(Iterator) setIterator} method is 
@@ -92,7 +94,8 @@ public class TransformIterator extends ProxyIterator {
      * @param iterator  the iterator to use
      */
     public TransformIterator(Iterator iterator) {
-        super(iterator);
+        super();
+        this.iterator = iterator;
     }
 
     /**
@@ -104,50 +107,83 @@ public class TransformIterator extends ProxyIterator {
      * @param transformer  the transformer to use
      */
     public TransformIterator(Iterator iterator, Transformer transformer) {
-        super(iterator);
+        super();
+        this.iterator = iterator;
         this.transformer = transformer;
     }
 
-    // Iterator interface
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
+    public boolean hasNext() {
-    public Object next() {
+        return iterator.hasNext();
-        return transform( super.next() );
     }
 
-    // Properties
-    //-------------------------------------------------------------------------
     /**
-     * Getter for property transformer.
+     * Gets the next object from the iteration, transforming it using the
+     * current transformer. If the transformer is null, no transformation
+     * occurs and the object from the iterator is returned directly.
      * 
-     * @return Value of property transformer.
+     * @return the next object
+     * @throws NoSuchElementException if there are no more elements
+     */
+    public Object next() {
+        return transform(iterator.next());
+    }
+
+    public void remove() {
+        iterator.remove();
+    }
+
+    //-----------------------------------------------------------------------
+    /** 
+     * Gets the iterator this iterator is using.
+     * 
+     * @return the iterator.
+     */
+    public Iterator getIterator() {
+        return iterator;
+    }
+
+    /** 
+     * Sets the iterator for this iterator to use.
+     * If iteration has started, this effectively resets the iterator.
+     * 
+     * @param iterator  the iterator to use
+     */
+    public void setIterator(Iterator iterator) {
+        this.iterator = iterator;
+    }
+
+    //-----------------------------------------------------------------------
+    /** 
+     * Gets the transformer this iterator is using.
+     * 
+     * @return the transformer.
      */
     public Transformer getTransformer() {
         return transformer;
     }
 
     /** 
-     * Setter for property transformer.
+     * Sets the transformer this the iterator to use.
+     * A null transformer is a no-op transformer.
      * 
-     * @param transformer New value of property transformer.
+     * @param transformer  the transformer to use
      */
     public void setTransformer(Transformer transformer) {
         this.transformer = transformer;
     }
 
-    // Implementation methods
+    //-----------------------------------------------------------------------
-    //-------------------------------------------------------------------------
-
     /**
-     *  Transforms the given object using the transformer.  If the 
+     * Transforms the given object using the transformer.
-     *  transformer is null, the original object is returned as-is.
+     * If the transformer is null, the original object is returned as-is.
      *
      * @param source  the object to transform
      * @return the transformed object
      */
-    protected Object transform( Object source ) {
+    protected Object transform(Object source) {
-        Transformer transformer = getTransformer();
+        if (transformer != null) {
-        if ( transformer != null ) {
+            return transformer.transform(source);
-            return transformer.transform( source );
         }
         return source;
     }