core/src/main/java/org/apache/struts2/components/IteratorComponent.java - struts - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License.  You may obtain a copy of the License at
  *
  *  http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  * KIND, either express or implied.  See the License for the
  * specific language governing permissions and limitations
  * under the License.
  */
 package org.apache.struts2.components;

 import com.opensymphony.xwork2.util.ValueStack;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.struts2.util.MakeIterator;
 import org.apache.struts2.views.annotations.StrutsTag;
 import org.apache.struts2.views.annotations.StrutsTagAttribute;
 import org.apache.struts2.views.jsp.IteratorStatus;

 import java.io.Writer;
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;

 /**
  * <!-- START SNIPPET: javadoc -->
  *
  * <p>Iterator will iterate over a value. An iterable value can be any of: java.util.Collection, java.util.Iterator,
  * java.util.Enumeration, java.util.Map, or an array.</p>
  *
  * <!-- END SNIPPET: javadoc -->
  *
  * <!-- START SNIPPET: params -->
  *
  * <ul>
  *
  * <li>status (String) - if specified, an instance of IteratorStatus will be pushed into stack upon each iteration</li>
  *
  * <li>value (Object) - the source to iterate over, must be iteratable, else the object itself will be put into a
  * newly created List (see MakeIterator#convert(Object)</li>
  *
  * <li>id (String) - if specified the current iteration object will be place with this id in Struts stack's context
  * scope</li>
  *
  * <li>begin (Integer) - if specified the iteration will start on that index</li>
  *
  * <li>end (Integer) - if specified the iteration will end on that index(inclusive)</li>
  *
  * <li>step (Integer) - if specified the iteration index will be increased by this value on each iteration. It can be a negative
  * value, in which case 'begin' must be greater than 'end'</li>
  *
  * </ul>
  *
  * <!-- END SNIPPET: params -->
  *
  * <!-- START SNIPPET: example1description -->
  *
  * <p>The following example retrieves the value of the getDays() method of the current object on the value stack and
  * uses it to iterate over. The &lt;s:property/&gt; tag prints out the current value of the iterator.</p>
  *
  * <!-- END SNIPPET: example1description -->
  *
  * <pre>
  * <!-- START SNIPPET: example1code -->
  * &lt;s:iterator value="days"&gt;
  *   &lt;p&gt;day is: &lt;s:property/&gt;&lt;/p&gt;
  * &lt;/s:iterator&gt;
  * <!-- END SNIPPET: example1code -->
  * </pre>
  *
  *
  * <!-- START SNIPPET: example2description -->
  *
  * <p>The following example uses a {@link Bean} tag and places it into the ActionContext. The iterator tag will retrieve
  * that object from the ActionContext and then calls its getDays() method as above. The status attribute is also used to
  * create an {@link IteratorStatus} object, which in this example, its odd() method is used to alternate row
  * colours:</p>
  *
  * <!-- END SNIPPET: example2description -->
  *
  *
  * <pre>
  * <!-- START SNIPPET: example2code -->
  *
  * &lt;s:bean name="org.apache.struts2.example.IteratorExample" var="it"&gt;
  *   &lt;s:param name="day" value="'foo'"/&gt;
  *   &lt;s:param name="day" value="'bar'"/&gt;
  * &lt;/s:bean&gt;
  *
  * &lt;table border="0" cellspacing="0" cellpadding="1"&gt;
  * &lt;tr&gt;
  *   &lt;th&gt;Days of the week&lt;/th&gt;
  * &lt;/tr&gt;
  *
  * &lt;s:iterator value="#it.days" status="rowstatus"&gt;
  *   &lt;tr&gt;
  *     &lt;s:if test="#rowstatus.odd == true"&gt;
  *       &lt;td style="background: grey"&gt;&lt;s:property/&gt;&lt;/td&gt;
  *     &lt;/s:if&gt;
  *     &lt;s:else&gt;
  *       &lt;td&gt;&lt;s:property/&gt;&lt;/td&gt;
  *     &lt;/s:else&gt;
  *   &lt;/tr&gt;
  * &lt;/s:iterator&gt;
  * &lt;/table&gt;
  *
  * <!-- END SNIPPET: example2code -->
  * </pre>
  *
  * <!--START SNIPPET: example3description -->
  *
  * <p> The next example will further demonstrate the use of the status attribute, using a DAO obtained from the action
  * class through OGNL, iterating over groups and their users (in a security context). The last() method indicates if the
  * current object is the last available in the iteration, and if not, we need to separate the users using a comma: </p>
  *
  * <!-- END SNIPPET: example3description -->
  *
  * <pre>
  * <!-- START SNIPPET: example3code -->
  *
  *  &lt;s:iterator value="groupDao.groups" status="groupStatus"&gt;
  *      &lt;tr class="&lt;s:if test="#groupStatus.odd == true "&gt;odd&lt;/s:if&gt;&lt;s:else&gt;even&lt;/s:else&gt;"&gt;
  *          &lt;td&gt;&lt;s:property value="name" /&gt;&lt;/td&gt;
  *          &lt;td&gt;&lt;s:property value="description" /&gt;&lt;/td&gt;
  *          &lt;td&gt;
  *              &lt;s:iterator value="users" status="userStatus"&gt;
  *                  &lt;s:property value="fullName" /&gt;&lt;s:if test="!#userStatus.last"&gt;,&lt;/s:if&gt;
  *              &lt;/s:iterator&gt;
  *          &lt;/td&gt;
  *      &lt;/tr&gt;
  *  &lt;/s:iterator&gt;
  *
  * <!-- END SNIPPET: example3code -->
  * </pre>
  *
  * <!-- START SNIPPET: example4description -->
  *
  * <p> The next example iterates over a an action collection and passes every iterator value to another action. The
  * trick here lies in the use of the '[0]' operator. It takes the current iterator value and passes it on to the edit
  * action. Using the '[0]' operator has the same effect as using &lt;s:property /&gt;. (The latter, however, does not
  * work from inside the param tag). </p>
  *
  * <!-- END SNIPPET: example4description -->
  *
  * <pre>
  * <!-- START SNIPPET: example4code -->
  *
  *      &lt;s:action name="entries" var="entries"/&gt;
  *      &lt;s:iterator value="#entries.entries" &gt;
  *          &lt;s:property value="name" /&gt;
  *          &lt;s:property /&gt;
  *          &lt;s:push value="..."&gt;
  *              &lt;s:action name="edit" var="edit" &gt;
  *                  &lt;s:param name="entry" value="[0]" /&gt;
  *              &lt;/s:action&gt;
  *          &lt;/push&gt;
  *      &lt;/s:iterator&gt;
  *
  * <!-- END SNIPPET: example4code -->
  * </pre>
  *
  * <!-- START SNIPPET: example5description -->
  *
  * <p>A loop that iterates 5 times</p>
  *
  * <!-- END SNIPPET: example5description -->
  *
  * <pre>
  * <!-- START SNIPPET: example5code -->
  *
  * &lt;s:iterator var="counter" begin="1" end="5" &gt;
  *    &lt;!-- current iteration value (1, ... 5) --&gt;
  *    &lt;s:property value="top" /&gt;
  * &lt;/s:iterator&gt;
  *
  * <!-- END SNIPPET: example5code -->
  * </pre>
  *
  * <!-- START SNIPPET: example6description -->
  *
  * <p>Another way to create a simple loop, similar to JSTL's
  * &lt;c:forEach begin="..." end="..." ...&gt; is to use some
  * OGNL magic, which provides some under-the-covers magic to
  * make 0-n loops trivial. This example also loops five times.</p>
  *
  * <!-- END SNIPPET: example6description -->
  *
  * <pre>
  * <!-- START SNIPPET: example6code -->
  *
  * &lt;s:iterator status="stat" value="(5).{ #this }" &gt;
  *    &lt;s:property value="#stat.count" /&gt; &lt;!-- Note that "count" is 1-based, "index" is 0-based. --&gt;
  * &lt;/s:iterator&gt;
  *
  * <!-- END SNIPPET: example6code -->
  * </pre>
  *
  *  <!-- START SNIPPET: example7description -->
  *
  * <p>A loop that iterates over a partial list</p>
  *
  * <!-- END SNIPPET: example7description -->
  *
  * <pre>
  * <!-- START SNIPPET: example7code -->
  *
  * &lt;s:iterator value="{1,2,3,4,5}" begin="2" end="4" &gt;
  *    &lt;!-- current iteration value (2,3,4) --&gt;
  *    &lt;s:property value="top" /&gt;
  * &lt;/s:iterator&gt;
  *
  * <!-- END SNIPPET: example7code -->
  * </pre>
  */
 @StrutsTag(name="iterator", tldTagClass="org.apache.struts2.views.jsp.IteratorTag", description="Iterate over a iterable value")
 public class IteratorComponent extends ContextBean {
     private static final Logger LOG = LogManager.getLogger(IteratorComponent.class);

     protected Iterator iterator;
     protected IteratorStatus status;
     protected Object oldStatus;
     protected IteratorStatus.StatusState statusState;
     protected String statusAttr;
     protected String value;
     protected String beginStr;
     protected Integer begin;
     protected String endStr;
     protected Integer end;
     protected String stepStr;
     protected Integer step;

     public IteratorComponent(ValueStack stack) {
         super(stack);
     }

     public boolean start(Writer writer) {
         //Create an iterator status if the status attribute was set.
         if (statusAttr != null) {
             statusState = new IteratorStatus.StatusState();
             status = new IteratorStatus(statusState);
         }

         if (beginStr != null)
             begin = (Integer) findValue(beginStr,  Integer.class);

         if (endStr != null)
             end = (Integer) findValue(endStr,  Integer.class);

         if (stepStr != null)
             step = (Integer) findValue(stepStr,  Integer.class);

         ValueStack stack = getStack();

         if (value == null && begin == null && end == null) {
             value = "top";
         }
         Object iteratorTarget = findValue(value);
         iterator = MakeIterator.convert(iteratorTarget);

         if (begin != null) {
             //default step to 1
             if (step == null)
                 step = 1;

             if (iterator == null) {
                 //classic for loop from 'begin' to 'end'
                 iterator = new CounterIterator(begin, end, step, null);
             } else {
                 //only arrays and lists are supported
                 if (iteratorTarget.getClass().isArray()) {
                     Object[] values = (Object[]) iteratorTarget;
                     if (end == null)
                         end = step > 0 ? values.length - 1 : 0;
                     iterator = new CounterIterator(begin, end, step, Arrays.asList(values));
                 } else if (iteratorTarget instanceof List) {
                     List values = (List) iteratorTarget;
                     if (end == null)
                         end = step > 0 ? values.size() - 1 : 0;
                     iterator = new CounterIterator(begin, end, step, values);
                 } else {
                     //so the iterator is not based on an array or a list
                     LOG.error("Incorrect use of the iterator tag. When 'begin' is set, 'value' must be" +
                             " an Array or a List, or not set at all. 'begin', 'end' and 'step' will be ignored");
                 }
             }
         }

         // get the first
         if ((iterator != null) && iterator.hasNext()) {
             Object currentValue = iterator.next();
             stack.push(currentValue);

             String var = getVar();

             if ((var != null)) {
                 putInContext(currentValue);
             }

             // Status object
             if (statusAttr != null) {
                 statusState.setLast(!iterator.hasNext());
                 oldStatus = stack.getContext().get(statusAttr);
                 stack.getContext().put(statusAttr, status);
             }

             return true;
         } else {
             super.end(writer, "");
             return false;
         }
     }

     public boolean end(Writer writer, String body) {
         ValueStack stack = getStack();
         if (iterator != null) {
             stack.pop();
         }

         if (iterator!=null && iterator.hasNext()) {
             Object currentValue = iterator.next();
             stack.push(currentValue);

             putInContext(currentValue);

             // Update status
             if (status != null) {
                 statusState.next(); // Increase counter
                 statusState.setLast(!iterator.hasNext());
             }

             return true;
         } else {
             // Reset status object in case someone else uses the same name in another iterator tag instance
             if (status != null) {
                 if (oldStatus == null) {
                     stack.getContext().put(statusAttr, null);
                 } else {
                     stack.getContext().put(statusAttr, oldStatus);
                 }
             }
             super.end(writer, "");
             return false;
         }
     }

     static class CounterIterator implements Iterator<Object> {
         private int step;
         private int end;
         private int currentIndex;
         private List<Object> values;

         CounterIterator(Integer begin, Integer end, Integer step, List<Object> values) {
             this.end = end;
             if (step != null)
                 this.step = step;
             this.currentIndex = begin - this.step;
             this.values = values;
         }

         public boolean hasNext() {
             int next = peekNextIndex();
             return step > 0 ? next <= end : next >= end;
         }

         public Object next() {
             if (hasNext()) {
                 int nextIndex = peekNextIndex();
                 currentIndex += step;
                 return values != null ? values.get(nextIndex) : nextIndex;
             } else {
                 throw new IndexOutOfBoundsException("Index " + ( currentIndex + step) + " must be less than or equal to " + end);
             }
         }

         private int peekNextIndex() {
            return currentIndex + step;
         }

         public void remove() {
             throw new UnsupportedOperationException("Values cannot be removed from this iterator");
         }
     }

     @StrutsTagAttribute(description="If specified, an instanceof IteratorStatus will be pushed into stack upon each iteration",
         type="Boolean", defaultValue="false")
     public void setStatus(String status) {
         this.statusAttr = status;
     }

     @StrutsTagAttribute(description="the iteratable source to iterate over, else an the object itself will be put into a newly created List")
     public void setValue(String value) {
         this.value = value;
     }

     @StrutsTagAttribute(description="if specified the iteration will start on that index", type="Integer", defaultValue="0")
     public void setBegin(String begin) {
         this.beginStr = begin;
     }

     @StrutsTagAttribute(description="if specified the iteration will end on that index(inclusive)", type="Integer",
             defaultValue="Size of the 'values' List or array, or 0 if 'step' is negative")
     public void setEnd(String end) {
         this.endStr = end;
     }

     @StrutsTagAttribute(description="if specified the iteration index will be increased by this value on each iteration. It can be a negative " +
             "value, in which case 'begin' must be greater than 'end'", type="Integer", defaultValue="1")
     public void setStep(String step) {
         this.stepStr = step;
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/
	package org.apache.struts2.components;

	import com.opensymphony.xwork2.util.ValueStack;
	import org.apache.logging.log4j.LogManager;
	import org.apache.logging.log4j.Logger;
	import org.apache.struts2.util.MakeIterator;
	import org.apache.struts2.views.annotations.StrutsTag;
	import org.apache.struts2.views.annotations.StrutsTagAttribute;
	import org.apache.struts2.views.jsp.IteratorStatus;

	import java.io.Writer;
	import java.util.Arrays;
	import java.util.Iterator;
	import java.util.List;

	/**
	* <!-- START SNIPPET: javadoc -->
	*
	* <p>Iterator will iterate over a value. An iterable value can be any of: java.util.Collection, java.util.Iterator,
	* java.util.Enumeration, java.util.Map, or an array.</p>
	*
	* <!-- END SNIPPET: javadoc -->
	*
	* <!-- START SNIPPET: params -->
	*
	* <ul>
	*
	* <li>status (String) - if specified, an instance of IteratorStatus will be pushed into stack upon each iteration</li>
	*
	* <li>value (Object) - the source to iterate over, must be iteratable, else the object itself will be put into a
	* newly created List (see MakeIterator#convert(Object)</li>
	*
	* <li>id (String) - if specified the current iteration object will be place with this id in Struts stack's context
	* scope</li>
	*
	* <li>begin (Integer) - if specified the iteration will start on that index</li>
	*
	* <li>end (Integer) - if specified the iteration will end on that index(inclusive)</li>
	*
	* <li>step (Integer) - if specified the iteration index will be increased by this value on each iteration. It can be a negative
	* value, in which case 'begin' must be greater than 'end'</li>
	*
	* </ul>
	*
	* <!-- END SNIPPET: params -->
	*
	* <!-- START SNIPPET: example1description -->
	*
	* <p>The following example retrieves the value of the getDays() method of the current object on the value stack and
	* uses it to iterate over. The <s:property/> tag prints out the current value of the iterator.</p>
	*
	* <!-- END SNIPPET: example1description -->
	*
	* <pre>
	* <!-- START SNIPPET: example1code -->
	* <s:iterator value="days">
	* <p>day is: <s:property/></p>
	* </s:iterator>
	* <!-- END SNIPPET: example1code -->
	* </pre>
	*
	*
	* <!-- START SNIPPET: example2description -->
	*
	* <p>The following example uses a {@link Bean} tag and places it into the ActionContext. The iterator tag will retrieve
	* that object from the ActionContext and then calls its getDays() method as above. The status attribute is also used to
	* create an {@link IteratorStatus} object, which in this example, its odd() method is used to alternate row
	* colours:</p>
	*
	* <!-- END SNIPPET: example2description -->
	*
	*
	* <pre>
	* <!-- START SNIPPET: example2code -->
	*
	* <s:bean name="org.apache.struts2.example.IteratorExample" var="it">
	* <s:param name="day" value="'foo'"/>
	* <s:param name="day" value="'bar'"/>
	* </s:bean>
	*
	* <table border="0" cellspacing="0" cellpadding="1">
	* <tr>
	* <th>Days of the week</th>
	* </tr>
	*
	* <s:iterator value="#it.days" status="rowstatus">
	* <tr>
	* <s:if test="#rowstatus.odd == true">
	* <td style="background: grey"><s:property/></td>
	* </s:if>
	* <s:else>
	* <td><s:property/></td>
	* </s:else>
	* </tr>
	* </s:iterator>
	* </table>
	*
	* <!-- END SNIPPET: example2code -->
	* </pre>
	*
	* <!--START SNIPPET: example3description -->
	*
	* <p> The next example will further demonstrate the use of the status attribute, using a DAO obtained from the action
	* class through OGNL, iterating over groups and their users (in a security context). The last() method indicates if the
	* current object is the last available in the iteration, and if not, we need to separate the users using a comma: </p>
	*
	* <!-- END SNIPPET: example3description -->
	*
	* <pre>
	* <!-- START SNIPPET: example3code -->
	*
	* <s:iterator value="groupDao.groups" status="groupStatus">
	* <tr class="<s:if test="#groupStatus.odd == true ">odd</s:if><s:else>even</s:else>">
	* <td><s:property value="name" /></td>
	* <td><s:property value="description" /></td>
	* <td>
	* <s:iterator value="users" status="userStatus">
	* <s:property value="fullName" /><s:if test="!#userStatus.last">,</s:if>
	* </s:iterator>
	* </td>
	* </tr>
	* </s:iterator>
	*
	* <!-- END SNIPPET: example3code -->
	* </pre>
	*
	* <!-- START SNIPPET: example4description -->
	*
	* <p> The next example iterates over a an action collection and passes every iterator value to another action. The
	* trick here lies in the use of the '[0]' operator. It takes the current iterator value and passes it on to the edit
	* action. Using the '[0]' operator has the same effect as using <s:property />. (The latter, however, does not
	* work from inside the param tag). </p>
	*
	* <!-- END SNIPPET: example4description -->
	*
	* <pre>
	* <!-- START SNIPPET: example4code -->
	*
	* <s:action name="entries" var="entries"/>
	* <s:iterator value="#entries.entries" >
	* <s:property value="name" />
	* <s:property />
	* <s:push value="...">
	* <s:action name="edit" var="edit" >
	* <s:param name="entry" value="[0]" />
	* </s:action>
	* </push>
	* </s:iterator>
	*
	* <!-- END SNIPPET: example4code -->
	* </pre>
	*
	* <!-- START SNIPPET: example5description -->
	*
	* <p>A loop that iterates 5 times</p>
	*
	* <!-- END SNIPPET: example5description -->
	*
	* <pre>
	* <!-- START SNIPPET: example5code -->
	*
	* <s:iterator var="counter" begin="1" end="5" >
	* <!-- current iteration value (1, ... 5) -->
	* <s:property value="top" />
	* </s:iterator>
	*
	* <!-- END SNIPPET: example5code -->
	* </pre>
	*
	* <!-- START SNIPPET: example6description -->
	*
	* <p>Another way to create a simple loop, similar to JSTL's
	* <c:forEach begin="..." end="..." ...> is to use some
	* OGNL magic, which provides some under-the-covers magic to
	* make 0-n loops trivial. This example also loops five times.</p>
	*
	* <!-- END SNIPPET: example6description -->
	*
	* <pre>
	* <!-- START SNIPPET: example6code -->
	*
	* <s:iterator status="stat" value="(5).{ #this }" >
	* <s:property value="#stat.count" /> <!-- Note that "count" is 1-based, "index" is 0-based. -->
	* </s:iterator>
	*
	* <!-- END SNIPPET: example6code -->
	* </pre>
	*
	* <!-- START SNIPPET: example7description -->
	*
	* <p>A loop that iterates over a partial list</p>
	*
	* <!-- END SNIPPET: example7description -->
	*
	* <pre>
	* <!-- START SNIPPET: example7code -->
	*
	* <s:iterator value="{1,2,3,4,5}" begin="2" end="4" >
	* <!-- current iteration value (2,3,4) -->
	* <s:property value="top" />
	* </s:iterator>
	*
	* <!-- END SNIPPET: example7code -->
	* </pre>
	*/
	@StrutsTag(name="iterator", tldTagClass="org.apache.struts2.views.jsp.IteratorTag", description="Iterate over a iterable value")
	public class IteratorComponent extends ContextBean {
	private static final Logger LOG = LogManager.getLogger(IteratorComponent.class);

	protected Iterator iterator;
	protected IteratorStatus status;
	protected Object oldStatus;
	protected IteratorStatus.StatusState statusState;
	protected String statusAttr;
	protected String value;
	protected String beginStr;
	protected Integer begin;
	protected String endStr;
	protected Integer end;
	protected String stepStr;
	protected Integer step;

	public IteratorComponent(ValueStack stack) {
	super(stack);
	}

	public boolean start(Writer writer) {
	//Create an iterator status if the status attribute was set.
	if (statusAttr != null) {
	statusState = new IteratorStatus.StatusState();
	status = new IteratorStatus(statusState);
	}

	if (beginStr != null)
	begin = (Integer) findValue(beginStr, Integer.class);

	if (endStr != null)
	end = (Integer) findValue(endStr, Integer.class);

	if (stepStr != null)
	step = (Integer) findValue(stepStr, Integer.class);

	ValueStack stack = getStack();

	if (value == null && begin == null && end == null) {
	value = "top";
	}
	Object iteratorTarget = findValue(value);
	iterator = MakeIterator.convert(iteratorTarget);

	if (begin != null) {
	//default step to 1
	if (step == null)
	step = 1;

	if (iterator == null) {
	//classic for loop from 'begin' to 'end'
	iterator = new CounterIterator(begin, end, step, null);
	} else {
	//only arrays and lists are supported
	if (iteratorTarget.getClass().isArray()) {
	Object[] values = (Object[]) iteratorTarget;
	if (end == null)
	end = step > 0 ? values.length - 1 : 0;
	iterator = new CounterIterator(begin, end, step, Arrays.asList(values));
	} else if (iteratorTarget instanceof List) {
	List values = (List) iteratorTarget;
	if (end == null)
	end = step > 0 ? values.size() - 1 : 0;
	iterator = new CounterIterator(begin, end, step, values);
	} else {
	//so the iterator is not based on an array or a list
	LOG.error("Incorrect use of the iterator tag. When 'begin' is set, 'value' must be" +
	" an Array or a List, or not set at all. 'begin', 'end' and 'step' will be ignored");
	}
	}
	}

	// get the first
	if ((iterator != null) && iterator.hasNext()) {
	Object currentValue = iterator.next();
	stack.push(currentValue);

	String var = getVar();

	if ((var != null)) {
	putInContext(currentValue);
	}

	// Status object
	if (statusAttr != null) {
	statusState.setLast(!iterator.hasNext());
	oldStatus = stack.getContext().get(statusAttr);
	stack.getContext().put(statusAttr, status);
	}

	return true;
	} else {
	super.end(writer, "");
	return false;
	}
	}

	public boolean end(Writer writer, String body) {
	ValueStack stack = getStack();
	if (iterator != null) {
	stack.pop();
	}

	if (iterator!=null && iterator.hasNext()) {
	Object currentValue = iterator.next();
	stack.push(currentValue);

	putInContext(currentValue);

	// Update status
	if (status != null) {
	statusState.next(); // Increase counter
	statusState.setLast(!iterator.hasNext());
	}

	return true;
	} else {
	// Reset status object in case someone else uses the same name in another iterator tag instance
	if (status != null) {
	if (oldStatus == null) {
	stack.getContext().put(statusAttr, null);
	} else {
	stack.getContext().put(statusAttr, oldStatus);
	}
	}
	super.end(writer, "");
	return false;
	}
	}

	static class CounterIterator implements Iterator<Object> {
	private int step;
	private int end;
	private int currentIndex;
	private List<Object> values;

	CounterIterator(Integer begin, Integer end, Integer step, List<Object> values) {
	this.end = end;
	if (step != null)
	this.step = step;
	this.currentIndex = begin - this.step;
	this.values = values;
	}

	public boolean hasNext() {
	int next = peekNextIndex();
	return step > 0 ? next <= end : next >= end;
	}

	public Object next() {
	if (hasNext()) {
	int nextIndex = peekNextIndex();
	currentIndex += step;
	return values != null ? values.get(nextIndex) : nextIndex;
	} else {
	throw new IndexOutOfBoundsException("Index " + ( currentIndex + step) + " must be less than or equal to " + end);
	}
	}

	private int peekNextIndex() {
	return currentIndex + step;
	}

	public void remove() {
	throw new UnsupportedOperationException("Values cannot be removed from this iterator");
	}
	}

	@StrutsTagAttribute(description="If specified, an instanceof IteratorStatus will be pushed into stack upon each iteration",
	type="Boolean", defaultValue="false")
	public void setStatus(String status) {
	this.statusAttr = status;
	}

	@StrutsTagAttribute(description="the iteratable source to iterate over, else an the object itself will be put into a newly created List")
	public void setValue(String value) {
	this.value = value;
	}

	@StrutsTagAttribute(description="if specified the iteration will start on that index", type="Integer", defaultValue="0")
	public void setBegin(String begin) {
	this.beginStr = begin;
	}

	@StrutsTagAttribute(description="if specified the iteration will end on that index(inclusive)", type="Integer",
	defaultValue="Size of the 'values' List or array, or 0 if 'step' is negative")
	public void setEnd(String end) {
	this.endStr = end;
	}

	@StrutsTagAttribute(description="if specified the iteration index will be increased by this value on each iteration. It can be a negative " +
	"value, in which case 'begin' must be greater than 'end'", type="Integer", defaultValue="1")
	public void setStep(String step) {
	this.stepStr = step;
	}
	}