jelly-tags/xml/src/main/java/org/apache/commons/jelly/tags/xml/SetTag.java - commons-jelly - 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.commons.jelly.tags.xml;

 import org.apache.commons.jelly.JellyTagException;
 import org.apache.commons.jelly.MissingAttributeException;
 import org.apache.commons.jelly.XMLOutput;
 import org.apache.commons.jelly.xpath.XPathComparator;
 import org.apache.commons.jelly.xpath.XPathTagSupport;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;

 import org.dom4j.Node;

 import org.jaxen.XPath;
 import org.jaxen.JaxenException;

 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.ListIterator;

 /** A tag which defines a variable from an XPath expression.
   * This function creates a variable of type {@link List} or {@link org.dom4j.Node}
   * (for example {@link org.dom4j.Element} or {@link org.dom4j.Attribute}).
   * Thus, the variable created from xml:set can be
   * used from the other xml library functions.
   *
   * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
   * @version $Revision$
   */
 public class SetTag extends XPathTagSupport {

     private static final int RETURN_NODE_LIST = 0;
     private static final int RETURN_FIRST_NODE = 1;
     private static final int RETURN_STRING_LIST = 2;
     private static final int RETURN_DELIMITED_STRING_LIST = 3;
     private static final int RETURN_FIRST_AS_STRING = 4;

     /** The Log to which logging calls will be made. */
     private Log log = LogFactory.getLog(SetTag.class);

     /** The variable name to export. */
     private String var;

     /** The XPath expression to evaluate. */
     private XPath select;

     /** Xpath comparator for sorting */
     private XPathComparator xpCmp = null;

     private Boolean single = null;

     private Boolean asString = null;

     private String delimiter = null;

     private String delim = null;

     public SetTag() {

     }

     // Tag interface
     //-------------------------------------------------------------------------
     public void doTag(XMLOutput output) throws MissingAttributeException, JellyTagException {
         if (var == null) {
             throw new MissingAttributeException( "var" );
         }
         if (select == null) {
             throw new MissingAttributeException( "select" );
         }

         Object xpathContext = getXPathContext();
         Object value = null;
         try {
             if( single != null && single.booleanValue() == true ) {
                 value = select.selectSingleNode(xpathContext);
             } else {
                 value = select.evaluate(xpathContext);
             }
         }
         catch (JaxenException e) {
             throw new JellyTagException(e);
         }

         if (value instanceof List) {
             List list = (List) value;
             // sort the list if xpCmp is set.
             if (xpCmp != null && (xpCmp.getXpath() != null)) {
                 Collections.sort(list, xpCmp);
             }
             if(list.isEmpty()) {
                 value = null;
             }
         }


         // handle single
         if (single!=null) {
             if (single.booleanValue() == true) {
                 if(value instanceof List) {
                     List l = (List) value;
                     if (l.size() == 0)
                         value=null;
                     else
                         value=l.get(0);
                 }
             } else { // single == false
                 if(! (value instanceof List) ) {
                     List l = null;
                     if (value==null) {
                         l = new ArrayList(0);
                     } else {
                         l = new ArrayList(1);
                         l.add(value);
                     }
                     value = l;
                 }
             }
         }

         // now convert the result(s) to string if need
         if(asString != null && asString.booleanValue()) {
             if(value instanceof Node) {
                 value = ((Node) value).getStringValue();
             } else if(value instanceof List) {
                 for(ListIterator it = ((List) value).listIterator(); it.hasNext(); ) {
                     Object v = it.next();
                     if(v instanceof Node) {
                         v = ((Node) v).getStringValue();
                         it.set(v);
                     }
                 }
             }
         }

         // finally convert the result to a concatenated string if delimiter is defined
         if(delimiter != null && value instanceof List) {
             StringBuffer buff = new StringBuffer();
             for(Iterator it = ((List) value).iterator(); it.hasNext(); ) {
                 Object v = it.next();
                 if (v instanceof Node) {
                     buff.append( ((Node) v).getStringValue());
                 } else {
                     buff.append(v.toString());
                 }
                 if(it.hasNext()) {
                     buff.append(delimiter);
                 }
             }
             buff.setLength(buff.length());
             value = buff.toString();
         }


         //log.info( "Evaluated xpath: " + select + " as: " + value + " of type: " + value.getClass().getName() );

         context.setVariable(var, value);
     }

     private List valueAsList( final Object value ) {
         if (value instanceof List) {
             return (List)value;
         } else {
             if (value == null) {
                 return Collections.EMPTY_LIST;
             } else {
                 return Collections.singletonList(value);
             }
         }
     }

     private Object valueAsSingle( final Object value ) {
         if (value instanceof List) {
             List l = (List) value;
             if (l.isEmpty())
                 return null;
             else
                 return l.get(0);
         } else {
             return value;
         }
     }

     private String singleValueAsString( final Object value ) {
         if (value instanceof Node) {
             return ((Node) value).getStringValue();
         } else {
             return null;
         }
     }

     private List nodeListToStringList( final List values ) {
         List l = new ArrayList(values.size());
         for (Iterator it = values.iterator(); it.hasNext(); ) {
             Object v = it.next();
             String s = singleValueAsString(v);
             if (s != null) {
                 l.add(s);
             }
         }
         return l;
     }

     private String joinDelimitedElements( final List values ) {
         StringBuffer sb = new StringBuffer();
         int sz = values.size();
         for (int i = 0; i < sz; i++) {
             String s = (String)values.get(i);
             sb.append(s);
             if (i < sz - 1)
                 sb.append(delim);
         }
         return sb.toString();
     }

     private int determineReturnType() {
         int resultType;
         if (single != null && single.booleanValue()) { // first node
             if (asString != null && asString.booleanValue()) {
                 resultType = RETURN_FIRST_AS_STRING;
             } else {
                 resultType = RETURN_FIRST_NODE;
             }
         } else { // all nodes
             if (asString != null && asString.booleanValue()) {
                 if (delim != null) {
                     resultType = RETURN_DELIMITED_STRING_LIST;
                 } else {
                     resultType = RETURN_STRING_LIST;
                 }
             } else {
                 resultType = RETURN_NODE_LIST;
             }
         }
         return resultType;
     }

     // Properties
     //-------------------------------------------------------------------------

     /** Sets the variable name to define for this expression
      */
     public void setVar(String var) {
         this.var = var;
     }

     /** Sets the XPath expression to evaluate. */
     public void setSelect(XPath select) {
         this.select = select;
     }

     /** If set to true will only take the first element matching.
         It then guarantees that the result is of type
         {@link org.dom4j.Node} thereby making sure that, for example,
         when an element is selected, one can directly call such methods
         as setAttribute.<br/>
         If set to false, guarantees that a list is returned.
         If set to false, guarantees that a list is returned.
         */
     public void setSingle(boolean single) {
         this.single = new Boolean(single);
     }

     /** If set to true, will ensure that the (XPath) text-value
       * of the selected node is taken instead of the node
       * itself.
       * This ensures that, thereafter, string manipulations
       * can be performed on the result.
       */
     public void setAsString(boolean asString) {
         this.asString = new Boolean(asString);
     }

     /** If set, returns a string delimited by this delimiter.
       * Implies <code>asString</code> to be true.
       */
     public void setDelim(String delim) {
         this.delimiter = delim;
         if( delim!=null ) {
             this.asString = Boolean.TRUE;
         }
     }

     /** Sets the xpath expression to use to sort selected nodes.
      *  Ignored if single is true.
      */
     public void setSort(XPath sortXPath) throws JaxenException {
         if (xpCmp == null) xpCmp = new XPathComparator();
         xpCmp.setXpath(sortXPath);
     }

     /**
      * Set whether to sort ascending or descending.
      */
     public void setDescending(boolean descending) {
         if (xpCmp == null) xpCmp = new XPathComparator();
         xpCmp.setDescending(descending);
     }
 }
	/*
	* 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.commons.jelly.tags.xml;

	import org.apache.commons.jelly.JellyTagException;
	import org.apache.commons.jelly.MissingAttributeException;
	import org.apache.commons.jelly.XMLOutput;
	import org.apache.commons.jelly.xpath.XPathComparator;
	import org.apache.commons.jelly.xpath.XPathTagSupport;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;

	import org.dom4j.Node;

	import org.jaxen.XPath;
	import org.jaxen.JaxenException;

	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.Iterator;
	import java.util.List;
	import java.util.ListIterator;

	/** A tag which defines a variable from an XPath expression.
	* This function creates a variable of type {@link List} or {@link org.dom4j.Node}
	* (for example {@link org.dom4j.Element} or {@link org.dom4j.Attribute}).
	* Thus, the variable created from xml:set can be
	* used from the other xml library functions.
	*
	* @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
	* @version $Revision$
	*/
	public class SetTag extends XPathTagSupport {

	private static final int RETURN_NODE_LIST = 0;
	private static final int RETURN_FIRST_NODE = 1;
	private static final int RETURN_STRING_LIST = 2;
	private static final int RETURN_DELIMITED_STRING_LIST = 3;
	private static final int RETURN_FIRST_AS_STRING = 4;

	/** The Log to which logging calls will be made. */
	private Log log = LogFactory.getLog(SetTag.class);

	/** The variable name to export. */
	private String var;

	/** The XPath expression to evaluate. */
	private XPath select;

	/** Xpath comparator for sorting */
	private XPathComparator xpCmp = null;

	private Boolean single = null;

	private Boolean asString = null;

	private String delimiter = null;

	private String delim = null;

	public SetTag() {

	}

	// Tag interface
	//-------------------------------------------------------------------------
	public void doTag(XMLOutput output) throws MissingAttributeException, JellyTagException {
	if (var == null) {
	throw new MissingAttributeException( "var" );
	}
	if (select == null) {
	throw new MissingAttributeException( "select" );
	}

	Object xpathContext = getXPathContext();
	Object value = null;
	try {
	if( single != null && single.booleanValue() == true ) {
	value = select.selectSingleNode(xpathContext);
	} else {
	value = select.evaluate(xpathContext);
	}
	}
	catch (JaxenException e) {
	throw new JellyTagException(e);
	}

	if (value instanceof List) {
	List list = (List) value;
	// sort the list if xpCmp is set.
	if (xpCmp != null && (xpCmp.getXpath() != null)) {
	Collections.sort(list, xpCmp);
	}
	if(list.isEmpty()) {
	value = null;
	}
	}


	// handle single
	if (single!=null) {
	if (single.booleanValue() == true) {
	if(value instanceof List) {
	List l = (List) value;
	if (l.size() == 0)
	value=null;
	else
	value=l.get(0);
	}
	} else { // single == false
	if(! (value instanceof List) ) {
	List l = null;
	if (value==null) {
	l = new ArrayList(0);
	} else {
	l = new ArrayList(1);
	l.add(value);
	}
	value = l;
	}
	}
	}

	// now convert the result(s) to string if need
	if(asString != null && asString.booleanValue()) {
	if(value instanceof Node) {
	value = ((Node) value).getStringValue();
	} else if(value instanceof List) {
	for(ListIterator it = ((List) value).listIterator(); it.hasNext(); ) {
	Object v = it.next();
	if(v instanceof Node) {
	v = ((Node) v).getStringValue();
	it.set(v);
	}
	}
	}
	}

	// finally convert the result to a concatenated string if delimiter is defined
	if(delimiter != null && value instanceof List) {
	StringBuffer buff = new StringBuffer();
	for(Iterator it = ((List) value).iterator(); it.hasNext(); ) {
	Object v = it.next();
	if (v instanceof Node) {
	buff.append( ((Node) v).getStringValue());
	} else {
	buff.append(v.toString());
	}
	if(it.hasNext()) {
	buff.append(delimiter);
	}
	}
	buff.setLength(buff.length());
	value = buff.toString();
	}


	//log.info( "Evaluated xpath: " + select + " as: " + value + " of type: " + value.getClass().getName() );

	context.setVariable(var, value);
	}

	private List valueAsList( final Object value ) {
	if (value instanceof List) {
	return (List)value;
	} else {
	if (value == null) {
	return Collections.EMPTY_LIST;
	} else {
	return Collections.singletonList(value);
	}
	}
	}

	private Object valueAsSingle( final Object value ) {
	if (value instanceof List) {
	List l = (List) value;
	if (l.isEmpty())
	return null;
	else
	return l.get(0);
	} else {
	return value;
	}
	}

	private String singleValueAsString( final Object value ) {
	if (value instanceof Node) {
	return ((Node) value).getStringValue();
	} else {
	return null;
	}
	}

	private List nodeListToStringList( final List values ) {
	List l = new ArrayList(values.size());
	for (Iterator it = values.iterator(); it.hasNext(); ) {
	Object v = it.next();
	String s = singleValueAsString(v);
	if (s != null) {
	l.add(s);
	}
	}
	return l;
	}

	private String joinDelimitedElements( final List values ) {
	StringBuffer sb = new StringBuffer();
	int sz = values.size();
	for (int i = 0; i < sz; i++) {
	String s = (String)values.get(i);
	sb.append(s);
	if (i < sz - 1)
	sb.append(delim);
	}
	return sb.toString();
	}

	private int determineReturnType() {
	int resultType;
	if (single != null && single.booleanValue()) { // first node
	if (asString != null && asString.booleanValue()) {
	resultType = RETURN_FIRST_AS_STRING;
	} else {
	resultType = RETURN_FIRST_NODE;
	}
	} else { // all nodes
	if (asString != null && asString.booleanValue()) {
	if (delim != null) {
	resultType = RETURN_DELIMITED_STRING_LIST;
	} else {
	resultType = RETURN_STRING_LIST;
	}
	} else {
	resultType = RETURN_NODE_LIST;
	}
	}
	return resultType;
	}

	// Properties
	//-------------------------------------------------------------------------

	/** Sets the variable name to define for this expression
	*/
	public void setVar(String var) {
	this.var = var;
	}

	/** Sets the XPath expression to evaluate. */
	public void setSelect(XPath select) {
	this.select = select;
	}

	/** If set to true will only take the first element matching.
	It then guarantees that the result is of type
	{@link org.dom4j.Node} thereby making sure that, for example,
	when an element is selected, one can directly call such methods
	as setAttribute.<br/>
	If set to false, guarantees that a list is returned.
	If set to false, guarantees that a list is returned.
	*/
	public void setSingle(boolean single) {
	this.single = new Boolean(single);
	}

	/** If set to true, will ensure that the (XPath) text-value
	* of the selected node is taken instead of the node
	* itself.
	* This ensures that, thereafter, string manipulations
	* can be performed on the result.
	*/
	public void setAsString(boolean asString) {
	this.asString = new Boolean(asString);
	}

	/** If set, returns a string delimited by this delimiter.
	* Implies <code>asString</code> to be true.
	*/
	public void setDelim(String delim) {
	this.delimiter = delim;
	if( delim!=null ) {
	this.asString = Boolean.TRUE;
	}
	}

	/** Sets the xpath expression to use to sort selected nodes.
	* Ignored if single is true.
	*/
	public void setSort(XPath sortXPath) throws JaxenException {
	if (xpCmp == null) xpCmp = new XPathComparator();
	xpCmp.setXpath(sortXPath);
	}

	/**
	* Set whether to sort ascending or descending.
	*/
	public void setDescending(boolean descending) {
	if (xpCmp == null) xpCmp = new XPathComparator();
	xpCmp.setDescending(descending);
	}
	}