Package components.xmltree

Interface XMLTree

All Known Implementing Classes:
XMLTree1, XMLTree2, XMLTreeSecondary
public interface XMLTree
XMLTree component with all its methods. (Note: by package-wide convention, all references are non-null.)

An XMLTree is modeled by a tree where each node has a label (either a tag or some text) and if the label is a tag, the node also has a set of (attribute, value) pairs.

There are two constructors. One takes the name of a file or a URL and a boolean flag, and constructs an XMLTree corresponding to the XML read from the file or URL. The boolean flag indicates whether leading/trailing whitespace should be trimmed from text nodes. The second constructor only takes the name of a file or a URL and behaves exactly as if the first constructor was invoked with a true flag (i.e., by default it trims whitespace).

  • Method Summary

    Modifier and Type
    Method
    Description
    Iterable<String>
    attributeNames()
    Returns an Iterable<String> of the attribute names of the root of this.
    String
    attributeValue(String name)
    Returns the value associated with the attribute of the root tag of this called name.
    XMLTree
    child(int k)
    Returns the k-th subtree of the root of this.
    void
    display()
    Displays this in a new window with a default title.
    void
    display(String title)
    Displays this in a new window with the given title.
    boolean
    hasAttribute(String name)
    Returns whether the root tag of this has an attribute called name.
    boolean
    isTag()
    Returns whether the label of the root of this is a tag.
    String
    label()
    Returns the label of the root of this.
    int
    numberOfChildren()
    Returns the number of subtrees of the root of this.
    String
    toString()
    Returns the XML string representation of this.

  • Method Details

    • label

      String label()
      Returns the label of the root of this.
      Returns:
      the label of the root of this
      Ensures:
      label = [the label of the root of this (not including <> for tags)]

    • isTag

      boolean isTag()
      Returns whether the label of the root of this is a tag.
      Returns:
      true iff the label of the root of this is a tag
      Ensures:
      isTag = [the label of the root of this is a tag]

    • hasAttribute

      boolean hasAttribute(String name)
      Returns whether the root tag of this has an attribute called name.
      Parameters:
      name - the name of the possible attribute
      Returns:
      true iff the root tag of this has an attribute called name
      Requires:
      [the label of the root of this is a tag]
      Ensures:
      hasAttribute =
  [label of the root of this has an attribute called name]

    • attributeValue

      String attributeValue(String name)
      Returns the value associated with the attribute of the root tag of this called name.
      Parameters:
      name - the name of the attribute
      Returns:
      the value associated to attribute name of the root tag of this
      Requires:
      [the label of the root of this is a tag and
   it has an attribute called name]
      Ensures:
      attributeValue =
  [the value associated with attribute name of the root tag of this]

    • numberOfChildren

      int numberOfChildren()
      Returns the number of subtrees of the root of this.
      Returns:
      the number of subtrees of the root of this
      Requires:
      [the label of the root of this is a tag]
      Ensures:
      numberOfChildren = [the number of subtrees of the root of this]

    • child

      XMLTree child(int k)
      Returns the k-th subtree of the root of this.
      Parameters:
      k - the subtree to return
      Returns:
      the k-th subtree of the root of this
      Requires:
      [the label of the root of this is a tag and
     0 <= k < the number of subtrees of the root of this]
      Ensures:
      child = [the k-th subtree of the root of this]

    • attributeNames

      Iterable<String> attributeNames()
      Returns an Iterable<String> of the attribute names of the root of this.
      Returns:
      an Iterable<String> of the attribute names of the root of this
      Requires:
      [the label of the root of this is a tag]
      Ensures:
      attributeNames =
  [an Iterable<String> of the attribute names of the root of this]

    • display

      void display()
      Displays this in a new window with a default title.
      Ensures:
      [this is displayed in a new window]

    • display

      void display(String title)
      Displays this in a new window with the given title.
      Parameters:
      title - the window title
      Ensures:
      [this is displayed in a new window]

    • toString

      String toString()
      Returns the XML string representation of this.
      Overrides:
      toString in class Object
      Returns:
      the XML string representation of this
      Ensures:
      toString = [the XML string representation of this]