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    1   /*
    2    * Copyright (c) 2002-2007 by OpenSymphony
    3    * All rights reserved.
    4    */
    5   package com.opensymphony.xwork2.interceptor;
    6   
    7   import com.opensymphony.xwork2.ActionInvocation;
    8   import com.opensymphony.xwork2.Unchainable;
    9   import com.opensymphony.xwork2.inject.Inject;
   10   import com.opensymphony.xwork2.util.CompoundRoot;
   11   import com.opensymphony.xwork2.util.ValueStack;
   12   import com.opensymphony.xwork2.util.logging.Logger;
   13   import com.opensymphony.xwork2.util.logging.LoggerFactory;
   14   import com.opensymphony.xwork2.util.reflection.ReflectionProvider;
   15   
   16   import java.util;
   17   
   18   
   19   /**
   20    * <!-- START SNIPPET: description -->
   21    *
   22    * An interceptor that copies all the properties of every object in the value stack to the currently executing object,
   23    * except for any object that implements {@link Unchainable}. A collection of optional <i>includes</i> and
   24    * <i>excludes</i> may be provided to control how and which parameters are copied. Only includes or excludes may be
   25    * specified. Specifying both results in undefined behavior. See the javadocs for {@link ReflectionProvider#copy(Object, Object,
   26    * java.util.Map, java.util.Collection, java.util.Collection)} for more information.
   27    *
   28    * <p/>
   29    * <b>Note:</b> It is important to remember that this interceptor does nothing if there are no objects already on the stack.
   30    * <br/>This means two things:
   31    * <br/><b>One</b>, you can safely apply it to all your actions without any worry of adverse affects.
   32    * <br/><b/>Two</b>, it is up to you to ensure an object exists in the stack prior to invoking this action. The most typical way this is done
   33    * is through the use of the <b>chain</b> result type, which combines with this interceptor to make up the action
   34    * chaining feature.
   35    *
   36    * <!-- END SNIPPET: description -->
   37    *
   38    * <p/> <u>Interceptor parameters:</u>
   39    *
   40    * <!-- START SNIPPET: parameters -->
   41    *
   42    * <ul>
   43    *
   44    * <li>excludes (optional) - the list of parameter names to exclude from copying (all others will be included).</li>
   45    *
   46    * <li>includes (optional) - the list of parameter names to include when copying (all others will be excluded).</li>
   47    *
   48    * </ul>
   49    *
   50    * <!-- END SNIPPET: parameters -->
   51    *
   52    * <p/> <u>Extending the interceptor:</u>
   53    *
   54    * <p/>
   55    *
   56    * <!-- START SNIPPET: extending -->
   57    *
   58    * There are no known extension points to this interceptor.
   59    *
   60    * <!-- END SNIPPET: extending -->
   61    *
   62    * <p/> <u>Example code:</u>
   63    *
   64    * <pre>
   65    * <!-- START SNIPPET: example -->
   66    * 
   67    * &lt;action name="someAction" class="com.examples.SomeAction"&gt;
   68    *     &lt;interceptor-ref name="basicStack"/&gt;
   69    *     &lt;result name="success" type="chain"&gt;otherAction&lt;/result&gt;
   70    * &lt;/action&gt;
   71    *
   72    * &lt;action name="otherAction" class="com.examples.OtherAction"&gt;
   73    *     &lt;interceptor-ref name="chain"/&gt;
   74    *     &lt;interceptor-ref name="basicStack"/&gt;
   75    *     &lt;result name="success"&gt;good_result.ftl&lt;/result&gt;
   76    * &lt;/action&gt;
   77    * 
   78    * <!-- END SNIPPET: example -->
   79    * </pre>
   80    *
   81    * @see com.opensymphony.xwork2.ActionChainResult
   82    * @author mrdon
   83    * @author tm_jee ( tm_jee(at)yahoo.co.uk )
   84    */
   85   public class ChainingInterceptor extends AbstractInterceptor {
   86   	
   87   	private static final Logger LOG = LoggerFactory.getLogger(ChainingInterceptor.class);
   88   	
   89       protected Collection<String> excludes;
   90       protected Collection<String> includes;
   91       
   92       protected ReflectionProvider reflectionProvider;
   93       
   94       @Inject
   95       public void setReflectionProvider(ReflectionProvider prov) {
   96           this.reflectionProvider = prov;
   97       }
   98   
   99       @Override
  100       public String intercept(ActionInvocation invocation) throws Exception {
  101           ValueStack stack = invocation.getStack();
  102           CompoundRoot root = stack.getRoot();
  103   
  104           if (root.size() > 1) {
  105               List<CompoundRoot> list = new ArrayList<CompoundRoot>(root);
  106               list.remove(0);
  107               Collections.reverse(list);
  108   
  109               Map<String, Object> ctxMap = invocation.getInvocationContext().getContextMap();
  110               Iterator<CompoundRoot> iterator = list.iterator();
  111               int index = 1; // starts with 1, 0 has been removed
  112               while (iterator.hasNext()) {
  113               	index = index + 1;
  114                   Object o = iterator.next();
  115                   if (o != null) {
  116                   	if (!(o instanceof Unchainable)) {
  117                   		reflectionProvider.copy(o, invocation.getAction(), ctxMap, excludes, includes);
  118                   	}
  119                   }
  120                   else {
  121                   	LOG.warn("compound root element at index "+index+" is null");
  122                   }
  123               }
  124           }
  125           
  126           return invocation.invoke();
  127       }
  128       
  129       /**
  130        * Gets list of parameter names to exclude
  131        *
  132        * @return the exclude list
  133        */
  134       public Collection<String> getExcludes() {
  135           return excludes;
  136       }
  137   
  138       /**
  139        * Sets the list of parameter names to exclude from copying (all others will be included).
  140        *
  141        * @param excludes  the excludes list
  142        */
  143       public void setExcludes(Collection<String> excludes) {
  144           this.excludes = excludes;
  145       }
  146   
  147       /**
  148        * Gets list of parameter names to include
  149        *
  150        * @return the include list
  151        */
  152       public Collection<String> getIncludes() {
  153           return includes;
  154       }
  155   
  156       /**
  157        * Sets the list of parameter names to include when copying (all others will be excluded).
  158        *
  159        * @param includes  the includes list
  160        */
  161       public void setIncludes(Collection<String> includes) {
  162           this.includes = includes;
  163       }
  164   
  165   }

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