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package org.w3c.dom;

The ElementTraversal interface is a set of read-only attributes which allow an author to easily navigate between elements in a document.

In conforming implementations of Element Traversal, all objects that implement Element must also implement the ElementTraversal interface. Four of the methods, getFirstElementChild, getLastElementChild, getPreviousElementSibling, and getNextElementSibling, each provides a live reference to another element with the defined relationship to the current element, if the related element exists. The fifth method, getChildElementCount, exposes the number of child elements of an element, for preprocessing before navigation.

See Also:
Since:9
/** * The {@code ElementTraversal} interface is a set of read-only attributes * which allow an author to easily navigate between elements in a document. * <p> * In conforming implementations of Element Traversal, all objects that * implement {@link Element} must also implement the {@code ElementTraversal} * interface. Four of the methods, * {@link #getFirstElementChild}, {@link #getLastElementChild}, * {@link #getPreviousElementSibling}, and {@link #getNextElementSibling}, * each provides a live reference to another element with the defined * relationship to the current element, if the related element exists. The * fifth method, {@link #getChildElementCount}, exposes the number of child * elements of an element, for preprocessing before navigation. * * @see * <a href='http://www.w3.org/TR/ElementTraversal/'><cite>Element Traversal Specification</cite></a> * * @since 9 */
public interface ElementTraversal {
Returns a reference to the first child node of the element which is of the Element type.
Returns:a reference to an element child, null if the element has no child of the Element type.
/** * Returns a reference to the first child node of the element which is of * the {@link Element} type. * * @return a reference to an element child, {@code null} if the element has * no child of the {@link Element} type. */
Element getFirstElementChild();
Returns a reference to the last child node of the element which is of the Element type.
Returns:a reference to an element child, null if the element has no child of the Element type.
/** * Returns a reference to the last child node of the element which is of * the {@link Element} type. * * @return a reference to an element child, {@code null} if the element has * no child of the {@link Element} type. */
Element getLastElementChild();
Returns a reference to the sibling node of the element which most immediately precedes the element in document order, and which is of the Element type.
Returns:a reference to an element child, null if the element has no sibling node of the Element type that comes before this one.
/** * Returns a reference to the sibling node of the element which most immediately * precedes the element in document order, and which is of the {@link Element} type. * * @return a reference to an element child, {@code null} if the element has * no sibling node of the {@link Element} type that comes before this one. */
Element getPreviousElementSibling();
Returns a reference to the sibling node of the element which most immediately follows the element in document order, and which is of the Element type.
Returns:a reference to an element child, null if the element has no sibling node of the Element type that comes after this one.
/** * Returns a reference to the sibling node of the element which most immediately * follows the element in document order, and which is of the {@link Element} type. * * @return a reference to an element child, {@code null} if the element has * no sibling node of the {@link Element} type that comes after this one. */
Element getNextElementSibling();
Returns the current number of child nodes of the element which are of the Element type.
Returns:the number of element children, or 0 if the element has no element children.
/** * Returns the current number of child nodes of the element which are of * the {@link Element} type. * * @return the number of element children, or {@code 0} if the element has * no element children. */
int getChildElementCount(); }