Class Element

java.lang.Object
org.jdom2.Content
org.jdom2.Element
All Implemented Interfaces:
Serializable, Cloneable, NamespaceAware, Parent
Direct Known Subclasses:
LocatedElement
public class Element extends Content implements Parent
An XML element. Methods allow the user to get and manipulate its child elements and content, directly access the element's textual content, manipulate its attributes, and manage namespaces.

See NamespaceAware and getNamespacesInScope() for more details on what the Namespace scope is and how it is managed in JDOM and specifically by this Element class.

Author:
Brett McLaughlin, Jason Hunter, Lucas Gonze, Kevin Regan, Dan Schaffer, Yusuf Goolamabbas, Kent C. Johnson, Jools Enticknap, Alex Rosen, Bradley S. Huffman, Victor Toni, Rolf Lear
See Also:

  • Field Details

    • name

      protected String name
      The local name of the element

    • namespace

      protected Namespace namespace
      The namespace of the element

  • Constructor Details

    • Element

      protected Element()
      This protected constructor is provided in order to support an Element subclass that wants full control over variable initialization. It intentionally leaves all instance variables null, allowing a lightweight subclass implementation. The subclass is responsible for ensuring all the get and set methods on Element behave as documented.

      When implementing an Element subclass which doesn't require full control over variable initialization, be aware that simply calling super() (or letting the compiler add the implicit super() call) will not initialize the instance variables which will cause many of the methods to throw a NullPointerException. Therefore, the constructor for these subclasses should call one of the public constructors so variable initialization is handled automatically.

    • Element

      public Element(String name, Namespace namespace)
      Creates a new element with the supplied (local) name and namespace. If the provided namespace is null, the element will have no namespace.
      Parameters:
      name - local name of the element
      namespace - namespace for the element
      Throws:
      IllegalNameException - if the given name is illegal as an element name

    • Element

      public Element(String name)
      Create a new element with the supplied (local) name and no namespace.
      Parameters:
      name - local name of the element
      Throws:
      IllegalNameException - if the given name is illegal as an element name.

    • Element

      public Element(String name, String uri)
      Creates a new element with the supplied (local) name and a namespace given by a URI. The element will be put into the unprefixed (default) namespace.
      Parameters:
      name - name of the element
      uri - namespace URI for the element
      Throws:
      IllegalNameException - if the given name is illegal as an element name or the given URI is illegal as a namespace URI

    • Element

      public Element(String name, String prefix, String uri)
      Creates a new element with the supplied (local) name and a namespace given by the supplied prefix and URI combination.
      Parameters:
      name - local name of the element
      prefix - namespace prefix
      uri - namespace URI for the element
      Throws:
      IllegalNameException - if the given name is illegal as an element name, the given prefix is illegal as a namespace prefix, or the given URI is illegal as a namespace URI

  • Method Details

    • getName

      public String getName()
      Returns the (local) name of the element (without any namespace prefix).
      Returns:
      local element name

    • setName

      public Element setName(String name)
      Sets the (local) name of the element.
      Parameters:
      name - the new (local) name of the element
      Returns:
      the target element
      Throws:
      IllegalNameException - if the given name is illegal as an Element name

    • getNamespace

      public Namespace getNamespace()
      Returns the element's Namespace.
      Returns:
      the element's namespace

    • setNamespace

      public Element setNamespace(Namespace namespace)
      Sets the element's Namespace. If the provided namespace is null, the element will have no namespace.
      Parameters:
      namespace - the new namespace. A null implies Namespace.NO_NAMESPACE.
      Returns:
      the target element
      Throws:
      IllegalAddException - if there is a Namespace conflict

    • getNamespacePrefix

      public String getNamespacePrefix()
      Returns the namespace prefix of the element or an empty string if none exists.
      Returns:
      the namespace prefix

    • getNamespaceURI

      public String getNamespaceURI()
      Returns the namespace URI mapped to this element's prefix (or the in-scope default namespace URI if no prefix). If no mapping is found, an empty string is returned.
      Returns:
      the namespace URI for this element

    • getNamespace

      public Namespace getNamespace(String prefix)
      Returns the Namespace corresponding to the given prefix in scope for this element. This involves searching up the tree, so the results depend on the current location of the element. Returns null if there is no namespace in scope with the given prefix at this point in the document.
      Parameters:
      prefix - namespace prefix to look up
      Returns:
      the Namespace for this prefix at this location, or null if none

    • getQualifiedName

      public String getQualifiedName()
      Returns the full name of the element, in the form [namespacePrefix]:[localName]. If the element does not have a namespace prefix, then the local name is returned.
      Returns:
      qualified name of the element (including namespace prefix)

    • addNamespaceDeclaration

      public boolean addNamespaceDeclaration(Namespace additionalNamespace)
      Adds a namespace declarations to this element. This should not be used to add the declaration for this element itself; that should be assigned in the construction of the element. Instead, this is for adding namespace declarations on the element not relating directly to itself. It's used during output to for stylistic reasons move namespace declarations higher in the tree than they would have to be.
      Parameters:
      additionalNamespace - namespace to add
      Returns:
      true if the namespace is added (false if it was previously added)
      Throws:
      IllegalAddException - if the namespace prefix collides with another namespace prefix on the element

    • removeNamespaceDeclaration

      public void removeNamespaceDeclaration(Namespace additionalNamespace)
      Removes an additional namespace declarations from this element. This should not be used to remove the declaration for this element itself; that should be handled in the construction of the element. Instead, this is for removing namespace declarations on the element not relating directly to itself. If the declaration is not present, this method does nothing.
      Parameters:
      additionalNamespace - namespace to remove. A null Namespace does nothing.

    • getAdditionalNamespaces

      public List<Namespace> getAdditionalNamespaces()
      Returns a list of the additional namespace declarations on this element. This includes only additional namespace, not the namespace of the element itself, which can be obtained through getNamespace(). If there are no additional declarations, this returns an empty list. Note, the returned list is unmodifiable.
      Returns:
      a List of the additional namespace declarations

    • getValue

      public String getValue()
      Returns the XPath 1.0 string value of this element, which is the complete, ordered content of all text node descendants of this element (i.e. the text that's left after all references are resolved and all other markup is stripped out.)
      Specified by:
      getValue in class Content
      Returns:
      a concatenation of all text node descendants

    • isRootElement

      public boolean isRootElement()
      Returns whether this element is a root element. This can be used in tandem with Content.getParent() to determine if an element has any "attachments" to a parent element or document.

      An element is a root element when it has a parent and that parent is a Document. In particular, this means that detached Elements are not root elements.

      Returns:
      whether this is a root element

    • getContentSize

      public int getContentSize()
      Description copied from interface: Parent
      Returns the number of children in this parent's content list. Children may be any Content type.
      Specified by:
      getContentSize in interface Parent
      Returns:
      number of children

    • indexOf

      public int indexOf(Content child)
      Description copied from interface: Parent
      Returns the index of the supplied child in the content list, or -1 if not a child of this parent.
      Specified by:
      indexOf in interface Parent
      Parameters:
      child - child to search for
      Returns:
      index of child, or -1 if not found

    • getText

      public String getText()
      Returns the textual content directly held under this element as a string. This includes all text within this single element, including whitespace and CDATA sections if they exist. It's essentially the concatenation of all Text and CDATA nodes returned by getContent(). The call does not recurse into child elements. If no textual value exists for the element, an empty string is returned.
      Returns:
      text content for this element, or empty string if none

    • getTextTrim

      public String getTextTrim()
      Returns the textual content of this element with all surrounding whitespace removed. If no textual value exists for the element, or if only whitespace exists, the empty string is returned.
      Returns:
      trimmed text content for this element, or empty string if none

    • getTextNormalize

      public String getTextNormalize()
      Returns the textual content of this element with all surrounding whitespace removed and internal whitespace normalized to a single space. If no textual value exists for the element, or if only whitespace exists, the empty string is returned.
      Returns:
      normalized text content for this element, or empty string if none

    • getChildText

      public String getChildText(String cname)
      Returns the textual content of the named child element, or null if there's no such child. This method is a convenience because calling getChild().getText() can throw a NullPointerException.
      Parameters:
      cname - the name of the child
      Returns:
      text content for the named child, or null if no such child

    • getChildTextTrim

      public String getChildTextTrim(String cname)
      Returns the trimmed textual content of the named child element, or null if there's no such child. See getTextTrim() for details of text trimming.
      Parameters:
      cname - the name of the child
      Returns:
      trimmed text content for the named child, or null if no such child

    • getChildTextNormalize

      public String getChildTextNormalize(String cname)
      Returns the normalized textual content of the named child element, or null if there's no such child. See getTextNormalize() for details of text normalizing.
      Parameters:
      cname - the name of the child
      Returns:
      normalized text content for the named child, or null if no such child

    • getChildText

      public String getChildText(String cname, Namespace ns)
      Returns the textual content of the named child element, or null if there's no such child.
      Parameters:
      cname - the name of the child
      ns - the namespace of the child. A null implies Namespace.NO_NAMESPACE.
      Returns:
      text content for the named child, or null if no such child

    • getChildTextTrim

      public String getChildTextTrim(String cname, Namespace ns)
      Returns the trimmed textual content of the named child element, or null if there's no such child.
      Parameters:
      cname - the name of the child
      ns - the namespace of the child. A null implies Namespace.NO_NAMESPACE.
      Returns:
      trimmed text content for the named child, or null if no such child

    • getChildTextNormalize

      public String getChildTextNormalize(String cname, Namespace ns)
      Returns the normalized textual content of the named child element, or null if there's no such child.
      Parameters:
      cname - the name of the child
      ns - the namespace of the child. A null implies Namespace.NO_NAMESPACE.
      Returns:
      normalized text content for the named child, or null if no such child

    • setText

      public Element setText(String text)
      Sets the content of the element to be the text given. All existing text content and non-text context is removed. If this element should have both textual content and nested elements, use setContent(Collection) instead. Setting a null text value is equivalent to setting an empty string value.
      Parameters:
      text - new text content for the element
      Returns:
      the target element
      Throws:
      IllegalDataException - if the assigned text contains an illegal character such as a vertical tab (as determined by Verifier.checkCharacterData(String))

    • coalesceText

      public boolean coalesceText(boolean recursively)
      Adjacent Text content is merged into the first Text in document order, and the redundant Text items are removed (including any empty Text).
      Parameters:
      recursively - true if you want the text of child elements coalesced too. False if you only want to coalesce this Element's Text.
      Returns:
      true if any content was changed by this operation.

    • getContent

      public List<Content> getContent()
      This returns the full content of the element as a List which may contain objects of type Text, Element, Comment, ProcessingInstruction, CDATA, and EntityRef. The List returned is "live" in document order and modifications to it affect the element's actual contents. Whitespace content is returned in its entirety.

      Sequential traversal through the List is best done with an Iterator since the underlying implement of List.size() may require walking the entire list.

      Specified by:
      getContent in interface Parent
      Returns:
      a List containing the mixed content of the element: may contain Text, Element, Comment, ProcessingInstruction, CDATA, and EntityRef objects.

    • getContent

      public <E extends Content> List<E> getContent(Filter<E> filter)
      Return a filter view of this Element's content.

      Sequential traversal through the List is best done with a Iterator since the underlying implement of List.size() may require walking the entire list.

      Specified by:
      getContent in interface Parent
      Type Parameters:
      E - The Generic type of the returned content (the Filter's type)
      Parameters:
      filter - Filter to apply Note that the Filters class has a number of predefined, useful filters.
      Returns:
      List - filtered Element content

    • removeContent

      public List<Content> removeContent()
      Removes all child content from this parent.
      Specified by:
      removeContent in interface Parent
      Returns:
      list of the old children detached from this parent

    • removeContent

      public <F extends Content> List<F> removeContent(Filter<F> filter)
      Remove all child content from this parent matching the supplied filter.
      Specified by:
      removeContent in interface Parent
      Type Parameters:
      F - The Generic type of the content to remove.
      Parameters:
      filter - filter to select which content to remove Note that the Filters class has a number of predefined, useful filters.
      Returns:
      list of the old children detached from this parent

    • setContent

      public Element setContent(Collection<? extends Content> newContent)
      This sets the content of the element. The supplied List should contain only objects of type Element, Text, CDATA, Comment, ProcessingInstruction, and EntityRef.

      When all objects in the supplied List are legal and before the new content is added, all objects in the old content will have their parentage set to null (no parent) and the old content list will be cleared. This has the effect that any active list (previously obtained with a call to getContent() or getChildren()) will also change to reflect the new content. In addition, all objects in the supplied List will have their parentage set to this element, but the List itself will not be "live" and further removals and additions will have no effect on this elements content. If the user wants to continue working with a "live" list, then a call to setContent should be followed by a call to getContent() or getChildren() to obtain a "live" version of the content.

      Passing a null or empty List clears the existing content.

      In event of an exception the original content will be unchanged and the objects in the supplied content will be unaltered.

      Parameters:
      newContent - Collection of content to set
      Returns:
      this element modified
      Throws:
      IllegalAddException - if the List contains objects of illegal types or with existing parentage.

    • setContent

      public Element setContent(int index, Content child)
      Replace the current child the given index with the supplied child.

      In event of an exception the original content will be unchanged and the supplied child will be unaltered.

      Parameters:
      index - - index of child to replace.
      child - - child to add.
      Returns:
      element on which this method was invoked
      Throws:
      IllegalAddException - if the supplied child is already attached or not legal content for this parent.
      IndexOutOfBoundsException - if index is negative or greater than the current number of children.

    • setContent

      public Parent setContent(int index, Collection<? extends Content> newContent)
      Replace the child at the given index with the supplied collection.

      In event of an exception the original content will be unchanged and the content in the supplied collection will be unaltered.

      Parameters:
      index - - index of child to replace.
      newContent - - Collection of content to replace child.
      Returns:
      object on which this method was invoked
      Throws:
      IllegalAddException - if the collection contains objects of illegal types.
      IndexOutOfBoundsException - if index is negative or greater than the current number of children.

    • addContent

      public Element addContent(String str)
      This adds text content to this element. It does not replace the existing content as does setText().
      Parameters:
      str - String to add
      Returns:
      this element modified
      Throws:
      IllegalDataException - if str contains an illegal character such as a vertical tab (as determined by Verifier.checkCharacterData(String))

    • addContent

      public Element addContent(Content child)
      Appends the child to the end of the element's content list.
      Specified by:
      addContent in interface Parent
      Parameters:
      child - child to append to end of content list
      Returns:
      the element on which the method was called
      Throws:
      IllegalAddException - if the given child already has a parent.

    • addContent

      public Element addContent(Collection<? extends Content> newContent)
      Appends all children in the given collection to the end of the content list. In event of an exception during add the original content will be unchanged and the objects in the supplied collection will be unaltered.
      Specified by:
      addContent in interface Parent
      Parameters:
      newContent - Collection of content to append
      Returns:
      the element on which the method was called
      Throws:
      IllegalAddException - if any item in the collection already has a parent or is of an inappropriate type.

    • addContent

      public Element addContent(int index, Content child)
      Inserts the child into the content list at the given index.
      Specified by:
      addContent in interface Parent
      Parameters:
      index - location for adding the collection
      child - child to insert
      Returns:
      the parent on which the method was called
      Throws:
      IndexOutOfBoundsException - if index is negative or beyond the current number of children
      IllegalAddException - if the given child already has a parent.

    • addContent

      public Element addContent(int index, Collection<? extends Content> newContent)
      Inserts the content in a collection into the content list at the given index. In event of an exception the original content will be unchanged and the objects in the supplied collection will be unaltered.
      Specified by:
      addContent in interface Parent
      Parameters:
      index - location for adding the collection
      newContent - Collection of content to insert
      Returns:
      the parent on which the method was called
      Throws:
      IndexOutOfBoundsException - if index is negative or beyond the current number of children
      IllegalAddException - if any item in the collection already has a parent or is of an inappropriate type.

    • cloneContent

      public List<Content> cloneContent()
      Description copied from interface: Parent
      Returns a list containing detached clones of this parent's content list.
      Specified by:
      cloneContent in interface Parent
      Returns:
      list of cloned child content

    • getContent

      public Content getContent(int index)
      Description copied from interface: Parent
      Returns the child at the given index.
      Specified by:
      getContent in interface Parent
      Parameters:
      index - location of desired child
      Returns:
      child at the given index

    • removeContent

      public boolean removeContent(Content child)
      Description copied from interface: Parent
      Removes a single child node from the content list.
      Specified by:
      removeContent in interface Parent
      Parameters:
      child - child to remove
      Returns:
      whether the removal occurred

    • removeContent

      public Content removeContent(int index)
      Description copied from interface: Parent
      Removes and returns the child at the given index, or returns null if there's no such child.
      Specified by:
      removeContent in interface Parent
      Parameters:
      index - index of child to remove
      Returns:
      detached child at given index or null if no

    • setContent

      public Element setContent(Content child)
      Set this element's content to be the supplied child.

      If the supplied child is legal content for this parent and before it is added, all content in the current content list will be cleared and all current children will have their parentage set to null.

      This has the effect that any active list (previously obtained with a call to one of the getContent() methods will also change to reflect the new content. In addition, all content in the supplied collection will have their parentage set to this parent. If the user wants to continue working with a "live" list of this parent's child, then a call to setContent should be followed by a call to one of the getContent() methods to obtain a "live" version of the children.

      Passing a null child clears the existing content.

      In event of an exception the original content will be unchanged and the supplied child will be unaltered.

      Parameters:
      child - new content to replace existing content
      Returns:
      the parent on which the method was called
      Throws:
      IllegalAddException - if the supplied child is already attached or not legal content for an Element

    • isAncestor

      public boolean isAncestor(Element element)
      Determines if this element is the ancestor of another element.
      Parameters:
      element - Element to check against
      Returns:
      true if this element is the ancestor of the supplied element

    • hasAttributes

      public boolean hasAttributes()
      Indicate whether this Element has any attributes. Where possible you should call this method before calling getAttributes() because calling getAttributes() will create the necessary Attribute List memory structures, even if there are no Attributes attached to the Element. Calling hasAttributes() first can save memory.
      Returns:
      true if this Element has attributes.

    • hasAdditionalNamespaces

      public boolean hasAdditionalNamespaces()
      Indicate whether this Element has any additional Namespace declarations. Where possible you should call this method before calling getAdditionalNamespaces() because calling getAttributes() will create an unnecessary List even if there are no Additional Namespaces attached to the Element. Calling this method first can save memory and time.
      Returns:
      true if this Element has additional Namespaces.

    • getAttributes

      public List<Attribute> getAttributes()

      This returns the complete set of attributes for this element, as a List of Attribute objects in no particular order, or an empty list if there are none.

      The returned list is "live" and changes to it affect the element's actual attributes.

      Use the methods hasAttributes() or getAttributesSize() if you just want to see whether there are attributes. Calling this method may be inefficient if there are no Attributes.
      Returns:
      attributes for the element

    • getAttributesSize

      public int getAttributesSize()
      Get the number of Attributes currently attached to this Element.
      Returns:
      the number of Attributes attached.

    • getAttribute

      public Attribute getAttribute(String attname)

      This returns the attribute for this element with the given name and within no namespace, or null if no such attribute exists.

      Parameters:
      attname - name of the attribute to return
      Returns:
      attribute for the element

    • getAttribute

      public Attribute getAttribute(String attname, Namespace ns)

      This returns the attribute for this element with the given name and within the given Namespace, or null if no such attribute exists.

      Parameters:
      attname - name of the attribute to return
      ns - Namespace to search within. A null implies Namespace.NO_NAMESPACE.
      Returns:
      attribute for the element

    • getAttributeValue

      public String getAttributeValue(String attname)

      This returns the attribute value for the attribute with the given name and within no namespace, null if there is no such attribute, and the empty string if the attribute value is empty.

      Parameters:
      attname - name of the attribute whose value to be returned
      Returns:
      the named attribute's value, or null if no such attribute

    • getAttributeValue

      public String getAttributeValue(String attname, String def)

      This returns the attribute value for the attribute with the given name and within no namespace, or the passed-in default if there is no such attribute.

      Parameters:
      attname - name of the attribute whose value to be returned
      def - a default value to return if the attribute does not exist
      Returns:
      the named attribute's value, or the default if no such attribute

    • getAttributeValue

      public String getAttributeValue(String attname, Namespace ns)

      This returns the attribute value for the attribute with the given name and within the given Namespace, null if there is no such attribute, and the empty string if the attribute value is empty.

      Parameters:
      attname - name of the attribute whose valud is to be returned
      ns - Namespace to search within. A null implies Namespace.NO_NAMESPACE.
      Returns:
      the named attribute's value, or null if no such attribute

    • getAttributeValue

      public String getAttributeValue(String attname, Namespace ns, String def)

      This returns the attribute value for the attribute with the given name and within the given Namespace, or the passed-in default if there is no such attribute.

      Parameters:
      attname - name of the attribute whose valud is to be returned
      ns - Namespace to search within. A null implies Namespace.NO_NAMESPACE.
      def - a default value to return if the attribute does not exist
      Returns:
      the named attribute's value, or the default if no such attribute

    • setAttributes

      public Element setAttributes(Collection<? extends Attribute> newAttributes)

      This sets the attributes of the element. The supplied Collection should contain only objects of type Attribute.

      When all objects in the supplied List are legal and before the new attributes are added, all old attributes will have their parentage set to null (no parent) and the old attribute list will be cleared. This has the effect that any active attribute list (previously obtained with a call to getAttributes()) will also change to reflect the new attributes. In addition, all attributes in the supplied List will have their parentage set to this element, but the List itself will not be "live" and further removals and additions will have no effect on this elements attributes. If the user wants to continue working with a "live" attribute list, then a call to setAttributes should be followed by a call to getAttributes() to obtain a "live" version of the attributes.

      Passing a null or empty List clears the existing attributes.

      In cases where the List contains duplicate attributes, only the last one will be retained. This has the same effect as calling setAttribute(Attribute) sequentially.

      In event of an exception the original attributes will be unchanged and the attributes in the supplied attributes will be unaltered.

      Parameters:
      newAttributes - Collection of attributes to set
      Returns:
      this element modified
      Throws:
      IllegalAddException - if the List contains objects that are not instances of Attribute, or if any of the Attribute objects have conflicting namespace prefixes.

    • setAttribute

      public Element setAttribute(String name, String value)

      This sets an attribute value for this element. Any existing attribute with the same name and namespace URI is removed.

      Parameters:
      name - name of the attribute to set
      value - value of the attribute to set
      Returns:
      this element modified
      Throws:
      IllegalNameException - if the given name is illegal as an attribute name.
      IllegalDataException - if the given attribute value is illegal character data (as determined by Verifier.checkCharacterData(String)).

    • setAttribute

      public Element setAttribute(String name, String value, Namespace ns)

      This sets an attribute value for this element. Any existing attribute with the same name and namespace URI is removed.

      Parameters:
      name - name of the attribute to set
      value - value of the attribute to set
      ns - namespace of the attribute to set. A null implies Namespace.NO_NAMESPACE.
      Returns:
      this element modified
      Throws:
      IllegalNameException - if the given name is illegal as an attribute name, or if the namespace is an unprefixed default namespace
      IllegalDataException - if the given attribute value is illegal character data (as determined by Verifier.checkCharacterData(String)).
      IllegalAddException - if the attribute namespace prefix collides with another namespace prefix on the element.

    • setAttribute

      public Element setAttribute(Attribute attribute)

      This sets an attribute value for this element. Any existing attribute with the same name and namespace URI is removed.

      Parameters:
      attribute - Attribute to set
      Returns:
      this element modified
      Throws:
      IllegalAddException - if the attribute being added already has a parent or if the attribute namespace prefix collides with another namespace prefix on the element.

    • removeAttribute

      public boolean removeAttribute(String attname)

      This removes the attribute with the given name and within no namespace. If no such attribute exists, this method does nothing.

      Parameters:
      attname - name of attribute to remove
      Returns:
      whether the attribute was removed

    • removeAttribute

      public boolean removeAttribute(String attname, Namespace ns)

      This removes the attribute with the given name and within the given Namespace. If no such attribute exists, this method does nothing.

      Parameters:
      attname - name of attribute to remove
      ns - namespace URI of attribute to remove. A null implies Namespace.NO_NAMESPACE.
      Returns:
      whether the attribute was removed

    • removeAttribute

      public boolean removeAttribute(Attribute attribute)

      This removes the supplied Attribute should it exist.

      Parameters:
      attribute - Reference to the attribute to be removed.
      Returns:
      whether the attribute was removed

    • toString

      public String toString()

      This returns a String representation of the Element, suitable for debugging. If the XML representation of the Element is desired, XMLOutputter.outputString(Element) should be used.

      Overrides:
      toString in class Object
      Returns:
      String - information about the Element

    • clone

      public Element clone()

      This returns a deep clone of this element. The new element is detached from its parent, and getParent() on the clone will return null.

      Specified by:
      clone in interface Parent
      Overrides:
      clone in class Content
      Returns:
      the clone of this element

    • getDescendants

      public IteratorIterable<Content> getDescendants()
      Returns an iterator that walks over all descendants in document order.
      Specified by:
      getDescendants in interface Parent
      Returns:
      an iterator to walk descendants

    • getDescendants

      public <F extends Content> IteratorIterable<F> getDescendants(Filter<F> filter)
      Returns an iterator that walks over all descendants in document order applying the Filter to return only content that match the filter rule. With filters you can match only Elements, only Comments, Elements or Comments, only Elements with a given name and/or prefix, and so on.
      Specified by:
      getDescendants in interface Parent
      Type Parameters:
      F - The generic type of the returned descendant data
      Parameters:
      filter - filter to select which descendants to see Note that the Filters class has a number of predefined, useful filters.
      Returns:
      an iterator to walk descendants within a filter

    • getChildren

      public List<Element> getChildren()
      This returns a List of all the child elements nested directly (one level deep) within this element, as Element objects. If this target element has no nested elements, an empty List is returned. The returned list is "live" in document order and changes to it affect the element's actual contents.

      Sequential traversal through the List is best done with a Iterator since the underlying implement of List.size() may not be the most efficient.

      No recursion is performed, so elements nested two levels deep would have to be obtained with: 

      
  for(Element oneLevelDeep : topElement.getChildren()) {
    List<Element> twoLevelsDeep = oneLevelDeep.getChildren();
    // Do something with these children
  }

      Returns:
      list of child Element objects for this element

    • getChildren

      public List<Element> getChildren(String cname)
      This returns a List of all the child elements nested directly (one level deep) within this element with the given local name and belonging to no namespace, returned as Element objects. If this target element has no nested elements with the given name outside a namespace, an empty List is returned. The returned list is "live" in document order and changes to it affect the element's actual contents.

      Please see the notes for getChildren() for a code example.

      Parameters:
      cname - local name for the children to match
      Returns:
      all matching child elements

    • getChildren

      public List<Element> getChildren(String cname, Namespace ns)
      This returns a List of all the child elements nested directly (one level deep) within this element with the given local name and belonging to the given Namespace, returned as Element objects. If this target element has no nested elements with the given name in the given Namespace, an empty List is returned. The returned list is "live" in document order and changes to it affect the element's actual contents.

      Please see the notes for getChildren() for a code example.

      Parameters:
      cname - local name for the children to match
      ns - Namespace to search within. A null implies Namespace.NO_NAMESPACE.
      Returns:
      all matching child elements

    • getChild

      public Element getChild(String cname, Namespace ns)
      This returns the first child element within this element with the given local name and belonging to the given namespace. If no elements exist for the specified name and namespace, null is returned.
      Parameters:
      cname - local name of child element to match. A null implies any name
      ns - Namespace to search within. A null implies any namespace.
      Returns:
      the first matching child element, or null if not found

    • getChild

      public Element getChild(String cname)
      This returns the first child element within this element with the given local name and belonging to no namespace. If no elements exist for the specified name and namespace, null is returned.
      Parameters:
      cname - local name of child element to match
      Returns:
      the first matching child element, or null if not found

    • removeChild

      public boolean removeChild(String cname)

      This removes the first child element (one level deep) with the given local name and belonging to no namespace. Returns true if a child was removed.

      Parameters:
      cname - the name of child elements to remove
      Returns:
      whether deletion occurred

    • removeChild

      public boolean removeChild(String cname, Namespace ns)

      This removes the first child element (one level deep) with the given local name and belonging to the given namespace. Returns true if a child was removed.

      Parameters:
      cname - the name of child element to remove
      ns - Namespace to search within. A null implies Namespace.NO_NAMESPACE.
      Returns:
      whether deletion occurred

    • removeChildren

      public boolean removeChildren(String cname)

      This removes all child elements (one level deep) with the given local name and belonging to no namespace. Returns true if any were removed.

      Parameters:
      cname - the name of child elements to remove
      Returns:
      whether deletion occurred

    • removeChildren

      public boolean removeChildren(String cname, Namespace ns)

      This removes all child elements (one level deep) with the given local name and belonging to the given namespace. Returns true if any were removed.

      Parameters:
      cname - the name of child elements to remove
      ns - Namespace to search within. A null implies Namespace.NO_NAMESPACE.
      Returns:
      whether deletion occurred

    • getNamespacesInScope

      public List<Namespace> getNamespacesInScope()
      Get the Namespaces that are in-scope on this Element. Element has the most complex rules for the namespaces-in-scope.

      The scope is built up from a number of sources following the rules of XML namespace inheritance as follows:

      • The Namespace.XML_NAMESPACE is added
      • The element's namespace is added (commonly Namespace.NO_NAMESPACE)
      • All the attributes are inspected and for those that have a namespace prefix then their Namespaces are included (the "default" namespace for attributes is not the same as the "default" namespace for the element that attribute is on).
      • All Namespaces declared on this Element using addNamespaceDeclaration(Namespace) are included.
      • If the element has a parent then the parent's Namespace scope is inspected, and any prefixes in the parent scope that are not yet bound in this Element's scope are included.
      • If the default Namespace (the no-prefix namespace) has not been encountered for this Element then Namespace.NO_NAMESPACE is included.
      The Element's Namespace scope consist of its inherited Namespaces and any modifications to that scope derived from the Element itself.

      Note that the Element's Namespace will always be reported first.

      Description copied from NamespaceAware.getNamespacesInScope():

      Obtain a list of all namespaces that are in scope for the current content.

      The contents of this list will always be the combination of getNamespacesIntroduced() and getNamespacesInherited().

      See NamespaceAware documentation for details on what the order of the Namespaces will be in the returned list.

      Specified by:
      getNamespacesInScope in interface NamespaceAware
      Overrides:
      getNamespacesInScope in class Content
      Returns:
      a read-only list of Namespaces.
      See Also:

    • getNamespacesInherited

      public List<Namespace> getNamespacesInherited()
      Description copied from interface: NamespaceAware
      Obtain a list of all namespaces that are in scope for this content, but were not introduced by this content.

      The contents of this list will always be a subset (but in the same order) of getNamespacesInScope(), and will never intersect getNamspacesIntroduced()

      Specified by:
      getNamespacesInherited in interface NamespaceAware
      Overrides:
      getNamespacesInherited in class Content
      Returns:
      a read-only list of Namespaces.

    • getNamespacesIntroduced

      public List<Namespace> getNamespacesIntroduced()
      Description copied from interface: NamespaceAware
      Obtain a list of all namespaces that are introduced to the XML tree by this node. Only Elements and Attributes can introduce namespaces, so all other Content types will return an empty list.

      The contents of this list will always be a subset (but in the same order) of getNamespacesInScope(), and will never intersect getNamspacesInherited()

      Specified by:
      getNamespacesIntroduced in interface NamespaceAware
      Overrides:
      getNamespacesIntroduced in class Content
      Returns:
      a read-only list of Namespaces.

    • detach

      public Element detach()
      Description copied from class: Content
      Detaches this child from its parent or does nothing if the child has no parent.

      This method can be overridden by particular Content subclasses to return a specific type of Content (co-variant return type). All overriding subclasses must call super.detach();

      Overrides:
      detach in class Content
      Returns:
      this child detached

    • canContainContent

      public void canContainContent(Content child, int index, boolean replace) throws IllegalAddException
      Description copied from interface: Parent
      Test whether this Parent instance can contain the specified content at the specified position.
      Specified by:
      canContainContent in interface Parent
      Parameters:
      child - The content to be checked
      index - The location where the content would be put.
      replace - true if the intention is to replace the content already at the index.
      Throws:
      IllegalAddException - if there is a problem with the content

    • sortContent

      public void sortContent(Comparator<? super Content> comparator)
      Sort the contents of this Element using a mechanism that is safe for JDOM content. See the notes on sortContent(Filter, Comparator) for how the algorithm works.

      Collections.sort(List, Comparator) is not appropriate for sorting the Lists returned from getContent() because those are 'live' lists, and the Collections.sort() method uses an algorithm that adds the content in the new location before removing it from the old. That creates validation issues with content attempting to attach to a parent before detaching first.

      This method provides a safe means to conveniently sort the content.

      Parameters:
      comparator - The Comparator to use for the sorting.

    • sortChildren

      public void sortChildren(Comparator<? super Element> comparator)
      Sort the child Elements of this Element using a mechanism that is safe for JDOM content. Other child content will be unaffected. See the notes on sortContent(Filter, Comparator) for how the algorithm works.

      Collections.sort(List, Comparator) is not appropriate for sorting the Lists returned from getContent() because those are 'live' lists, and the Collections.sort() method uses an algorithm that adds the content in the new location before removing it from the old. This creates validation issues with content attempting to attach to a parent before detaching first.

      This method provides a safe means to conveniently sort the content.

      Parameters:
      comparator - The Comparator to use for the sorting.

    • sortAttributes

      public void sortAttributes(Comparator<? super Attribute> comparator)
      Sort the Attributes of this Element using a mechanism that is safe for JDOM. Other child content will be unaffected. See the notes on sortContent(Filter, Comparator) for how the algorithm works.

      Collections.sort(List, Comparator) is not appropriate for sorting the Lists returned from getContent() because those are 'live' lists, and the Collections.sort() method uses an algorithm that adds the content in the new location before removing it from the old. This creates validation issues with content attempting to attach to a parent before detaching first.

      This method provides a safe means to conveniently sort the content.

      A null comparator will sort the Attributes alphabetically first by prefix, then by name

      Parameters:
      comparator - The Comparator to use for the sorting.

    • sortContent

      public <E extends Content> void sortContent(Filter<E> filter, Comparator<? super E> comparator)
      Sort the child content of this Element that matches the Filter, using a mechanism that is safe for JDOM content. Other child content (that does not match the filter) will be unaffected.

      The algorithm used for sorting affects the child content in the following ways:

      1. Items not matching the Filter will be unchanged. This includes the absolute position of that content in this Element. i.e. if child content cc does not match the Filter, then indexOf(cc) will not be changed by this sort.
      2. Items matching the Filter will be reordered according to the comparator. Only the relative order of the Filtered data will change.
      3. Items that compare as 'equals' using the comparator will keep the the same relative order as before the sort.

      Collections.sort(List, Comparator) is not appropriate for sorting the Lists returned from getContent() because those are 'live' lists, and the Collections.sort() method uses an algorithm that adds the content in the new location before removing it from the old. This creates validation issues with content attempting to attach to a parent before detaching first.

      This method provides a safe means to conveniently sort the content.

      Type Parameters:
      E - The generic type of the Filter used to select the content to sort.
      Parameters:
      filter - The Filter used to select which child content to sort. Note that the Filters class has a number of predefined, useful filters.
      comparator - The Comparator to use for the sorting.

    • getXMLBaseURI

      public URI getXMLBaseURI() throws URISyntaxException
      Calculate the XMLBase URI for this Element using the rules defined in the XMLBase specification, as well as the values supplied in the xml:base attributes on this Element and its ancestry.

      This method assumes that all values in xml:base attributes are valid URI values according to the java.net.URI implementation. The same implementation is used to resolve relative URI values, and thus this code follows the assumptions in java.net.URI.

      This technically deviates from the XMLBase spec because to fully support legacy HTML the xml:base attribute could contain what is called a 'LIERI' which is a superset of true URI values, but for practical purposes JDOM users should never encounter such values because they are not processing raw HTML (but xhtml maybe).

      Returns:
      a URI representing the XMLBase value for the supplied Element, or null if one could not be calculated.
      Throws:
      URISyntaxException - if it is not possible to create java.net.URI values from the data in the xml:base attributes.