Package org.apache.velocity.tools.generic

Class XmlTool

  • All Implemented Interfaces:
    java.io.Serializable
    @DefaultKey("xml")
public class XmlTool
extends SafeConfig
implements java.io.Serializable

    Tool for reading/navigating XML files, with XPath expressions support.

    Configuration parameters:

    • resource=file or classpath resource
    • source=URL

    Here's a short example:

     XML file:
   <foo><bar>woogie</bar><a name="test"/></foo>

 Template:
   $foo.bar.text
   $foo.find('a')
   $foo.a.name

 Output:
   woogie
   <a name="test"/>
   test

 Configuration:
 <tools>
   <toolbox scope="application">
     <tool class="org.apache.velocity.tools.generic.XmlTool"
              key="foo" source="doc.xml"/>
   </toolbox>
 </tools>

    Note that this tool is included in the default GenericTools configuration under the key "xml". You can read but unless you set safeMode="false" for it, you will only be able to parse XML strings. Safe mode is on by default and blocks access to the read(String) method.

    Since:
    VelocityTools 2.0
    Version:
    $Revision: 1769055 $ $Date: 2006-11-27 10:49:37 -0800 (Mon, 27 Nov 2006) $
    Author:
    Nathan Bubna, Claude Brisson
    See Also:
    Serialized Form

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  XmlTool.NodeIterator
      Iterator implementation that wraps a Node list iterator to return new XmlTool instances for each item in the wrapped iterator.s

    • Constructor Summary

      Constructors 
      Constructor Description
      XmlTool()
      Default constructor.
      XmlTool​(java.util.List<org.w3c.dom.Node> nodes)
      Builds an XmlTool around a nodes list.
      XmlTool​(org.w3c.dom.Node node)
      Builds an XmlTool around a node.

    • Method Summary

      All Methods Instance Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      java.lang.String attr​(java.lang.Object o)
      Returns the value of the specified attribute for the first/sole Node in the internal Node list for this instance, if that Node is an Element.
      java.util.Map<java.lang.String,​java.lang.String> attributes()
      Returns a Map of all attributes for the first/sole Node held internally by this instance.
      XmlTool children()
      Returns a new XmlTool instance that wraps all the child Elements of all the current internally held nodes that are Elements themselves.
      protected void configure​(ValueParser values)
      Configuration.
      XmlTool fetch​(java.lang.String url)
      Reads and parses a remote or local URL
      XmlTool find​(java.lang.Object o)
      Converts the specified object to a String and calls find(String) with that.
      XmlTool find​(java.lang.String xpath)
      Performs an XPath selection on the current set of Nodes held by this instance and returns a new XmlTool instance that wraps those results.
      XmlTool get​(java.lang.Number n)
      Returns an XmlTool that wraps the specified Node from this instance's internal Node list.
      java.lang.Object get​(java.lang.Object o)
      This will first attempt to find an attribute with the specified name and return its value.
      XmlTool getFirst()
      Returns an XmlTool that wraps only the first Node from this instance's internal Node list.
      XmlTool getLast()
      Returns an XmlTool that wraps only the last Node from this instance's internal Node list.
      java.lang.Object getName()
      Asks get(Object) for a "name" result.
      java.lang.String getNodeName()
      Returns the name of the root node.
      java.lang.String getNodePath()
      Returns the XPath that identifies the first/sole Node represented by this instance.
      XmlTool getParent()
      Returns a new XmlTool instance that wraps the parent Element of the first/sole Node being wrapped by this instance.
      java.lang.String getPath()
      Deprecated.
      use getNodePath()
      java.lang.String getText()
      Returns the concatenated text content of all the internally held nodes.
      protected void initializeImportSupport​(ValueParser config)
      ImportSupport initialization
      boolean isEmpty()
      Returns true if there are no Nodes internally held by this instance.
      java.util.Iterator<XmlTool> iterator()
      Returns an Iterator that returns new XmlTool instances for each Node held internally by this instance.
      org.w3c.dom.Node node()
      Returns the first/sole Node from this instance's internal Node list, if any.
      XmlTool parents()
      Returns a new XmlTool instance that wraps the parent Elements of each of the Nodes being wrapped by this instance.
      XmlTool parse​(java.lang.String xml)
      Parses the given XML string and uses the resulting Document as the root Node.
      XmlTool read​(java.lang.String resource)
      Reads and parses a local resource file
      protected void setRoot​(org.w3c.dom.Node node)
      Sets a singular root Node for this instance.
      int size()
      Returns the number of Nodes internally held by this instance.
      java.lang.String toString()
      If this instance has no XML Nodes, then this returns the result of super.toString().

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • importSupport

        protected transient ImportSupport importSupport
        ImportSupport utility which provides underlying i/o

    • Constructor Detail

      • XmlTool

        public XmlTool()
        Default constructor.

      • XmlTool

        public XmlTool​(org.w3c.dom.Node node)
        Builds an XmlTool around a node.
        Parameters:
        node - target node

      • XmlTool

        public XmlTool​(java.util.List<org.w3c.dom.Node> nodes)
        Builds an XmlTool around a nodes list.
        Parameters:
        nodes - nodes list

    • Method Detail

      • initializeImportSupport

        protected void initializeImportSupport​(ValueParser config)
        ImportSupport initialization
        Parameters:
        config - configuration values

      • configure

        protected void configure​(ValueParser values)
        Configuration.
        Overrides:
        configure in class SafeConfig
        Parameters:
        values - configuration values

      • setRoot

        protected void setRoot​(org.w3c.dom.Node node)
        Sets a singular root Node for this instance.
        Parameters:
        node - new root node

      • parse

        public XmlTool parse​(java.lang.String xml)
        Parses the given XML string and uses the resulting Document as the root Node.
        Parameters:
        xml - XML string
        Returns:
        new XmlTool

      • read

        public XmlTool read​(java.lang.String resource)
        Reads and parses a local resource file
        Parameters:
        resource - resource path
        Returns:
        new XmlTool

      • fetch

        public XmlTool fetch​(java.lang.String url)
        Reads and parses a remote or local URL
        Parameters:
        url - resource URL
        Returns:
        new XmlTool

      • get

        public java.lang.Object get​(java.lang.Object o)
        This will first attempt to find an attribute with the specified name and return its value. If no such attribute exists or its value is null, this will attempt to convert the given value to a Number and get the result of get(Number). If the number conversion fails, then this will convert the object to a string. If that string does not contain a '/', it appends the result of getPath() and a '/' to the front of it. Finally, it delegates the string to the find(String) method and returns the result of that.
        Parameters:
        o - attribute name, number, xpath relative expression
        Returns:
        found value or null

      • getName

        public java.lang.Object getName()
        Asks get(Object) for a "name" result. If none, this will return the result of getNodeName().
        Returns:
        found value or null

      • getNodeName

        public java.lang.String getNodeName()
        Returns the name of the root node. If the internal Node list has more than one Node, it will only return the name of the first node in the list.
        Returns:
        node name

      • getPath

        @Deprecated
public java.lang.String getPath()
        Deprecated.
        use getNodePath()

        Returns the XPath that identifies the first/sole Node represented by this instance.

        This function is deprecated. In future versions, this function will first try get("path") before resorting to getNodePath().

        Returns:
        xpath node path

      • getNodePath

        public java.lang.String getNodePath()
        Returns the XPath that identifies the first/sole Node represented by this instance.
        Returns:
        xpath node path
        Since:
        3.2

      • attr

        public java.lang.String attr​(java.lang.Object o)
        Returns the value of the specified attribute for the first/sole Node in the internal Node list for this instance, if that Node is an Element. If it is a non-Element node type or there is no value for that attribute in this element, then this will return null.
        Parameters:
        o - attribute name
        Returns:
        attribute value or null

      • attributes

        public java.util.Map<java.lang.String,​java.lang.String> attributes()
        Returns a Map of all attributes for the first/sole Node held internally by this instance. If that Node is not an Element, this will return null.
        Returns:
        attributes map

      • isEmpty

        public boolean isEmpty()
        Returns true if there are no Nodes internally held by this instance.
        Returns:
        whether the set of current nodes is empty

      • size

        public int size()
        Returns the number of Nodes internally held by this instance.
        Returns:
        the size of the set of current nodes

      • iterator

        public java.util.Iterator<XmlTool> iterator()
        Returns an Iterator that returns new XmlTool instances for each Node held internally by this instance.
        Returns:
        an iterator on wrappers of current nodes or null

      • getFirst

        public XmlTool getFirst()
        Returns an XmlTool that wraps only the first Node from this instance's internal Node list.
        Returns:
        a wrapper on the first node or null

      • getLast

        public XmlTool getLast()
        Returns an XmlTool that wraps only the last Node from this instance's internal Node list.
        Returns:
        a wrapper on the last node or null

      • get

        public XmlTool get​(java.lang.Number n)
        Returns an XmlTool that wraps the specified Node from this instance's internal Node list.
        Parameters:
        n - node index in current nodes list
        Returns:
        a wrapper on the nth node or null

      • node

        public org.w3c.dom.Node node()
        Returns the first/sole Node from this instance's internal Node list, if any.
        Returns:
        the unwrapped first node or null

      • find

        public XmlTool find​(java.lang.Object o)
        Converts the specified object to a String and calls find(String) with that.
        Parameters:
        o - xpath to search
        Returns:
        a wrapper on found nodes or null

      • find

        public XmlTool find​(java.lang.String xpath)
        Performs an XPath selection on the current set of Nodes held by this instance and returns a new XmlTool instance that wraps those results. If the specified value is null or this instance does not currently hold any nodes, then this will return null. If the specified value, when converted to a string, does not contain a '/' character, then it has "//" prepended to it. This means that a call to $xml.find("a") is equivalent to calling $xml.find("//a"). The full range of XPath selectors is supported here.
        Parameters:
        xpath - xpath to search
        Returns:
        a wrapper on found nodes or null

      • getParent

        public XmlTool getParent()
        Returns a new XmlTool instance that wraps the parent Element of the first/sole Node being wrapped by this instance.
        Returns:
        wrapper on the parent of the first node or null

      • parents

        public XmlTool parents()
        Returns a new XmlTool instance that wraps the parent Elements of each of the Nodes being wrapped by this instance. This does not return all ancestors, just the immediate parents.
        Returns:
        a wrapper on the set of parents nodes or null

      • children

        public XmlTool children()
        Returns a new XmlTool instance that wraps all the child Elements of all the current internally held nodes that are Elements themselves.
        Returns:
        a wrapper on the children of current nodes

      • getText

        public java.lang.String getText()
        Returns the concatenated text content of all the internally held nodes. Obviously, this is most useful when only one node is held.
        Returns:
        text of current nodes or null

      • toString

        public java.lang.String toString()
        If this instance has no XML Nodes, then this returns the result of super.toString(). Otherwise, it returns the XML (as a string) of all the internally held nodes that are not Attributes. For attributes, only the value is used.
        Overrides:
        toString in class java.lang.Object
        Returns:
        XML string of current nodes or null