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    1   /*
    2    * Copyright 2002,2004 The Apache Software Foundation.
    3    *
    4    * Licensed under the Apache License, Version 2.0 (the "License");
    5    * you may not use this file except in compliance with the License.
    6    * You may obtain a copy of the License at
    7    *
    8    *      http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  package org.apache.commons.jelly.tags.core;
    17
    18  import java.lang.reflect.InvocationTargetException;
    19  import java.util.Map;
    20
    21  import org.apache.commons.beanutils.BeanUtils;
    22
    23  import org.apache.commons.jelly.JellyException;
    24  import org.apache.commons.jelly.JellyTagException;
    25  import org.apache.commons.jelly.MissingAttributeException;
    26  import org.apache.commons.jelly.MapTagSupport;
    27  import org.apache.commons.jelly.XMLOutput;
    28  import org.apache.commons.jelly.impl.BeanSource;
    29
    30  /***
    31   * A tag which sets the bean properties on the given bean.
    32   * So if you used it as follows, for example using the &lt;j:new&gt; tag.
    33   * <pre>
    34   * &lt;j:new className="com.acme.Person" var="person"/&gt;
    35   * &lt;j:setProperties object="${person}" name="James" location="${loc}"/&gt;
    36   * </pre>
    37   * Then it would set the name and location properties on the bean denoted by
    38   * the expression ${person}.
    39   * <p>
    40   * This tag can also be nested inside a bean tag such as the &lt;useBean&gt; tag
    41   * or a JellySwing tag to set one or more properties, maybe inside some conditional
    42   * logic.
    43   *
    44   * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
    45   * @version $Revision: 155420 $
    46   */
    47  public class SetPropertiesTag extends MapTagSupport  {
    48
    49      public SetPropertiesTag(){
    50      }
    51
    52      // Tag interface
    53      //-------------------------------------------------------------------------
    54      public void doTag(XMLOutput output) throws MissingAttributeException, JellyTagException {
    55          Map attributes = getAttributes();
    56          Object bean = attributes.remove( "object" );
    57          if ( bean == null ) {
    58              // lets try find a parent bean
    59              BeanSource tag = (BeanSource) findAncestorWithClass(BeanSource.class);
    60              if (tag != null) {
    61                  try {
    62                      bean = tag.getBean();
    63                  } catch (JellyException e) {
    64                      throw new JellyTagException(e);
    65                  }
    66              }
    67              if (bean == null) {
    68                  throw new MissingAttributeException("bean");
    69              }
    70          }
    71          setBeanProperties(bean, attributes);
    72      }
    73
    74      // Implementation methods
    75      //-------------------------------------------------------------------------
    76
    77      /***
    78       * Sets the properties on the bean. Derived tags could implement some custom
    79       * type conversion etc.
    80       */
    81      protected void setBeanProperties(Object bean, Map attributes) throws JellyTagException {
    82          try {
    83              BeanUtils.populate(bean, attributes);
    84          } catch (IllegalAccessException e) {
    85              throw new JellyTagException("could not set the properties on a bean",e);
    86          } catch (InvocationTargetException e) {
    87              throw new JellyTagException("could not set the properties on a bean",e);
    88          }
    89      }
    90  }