public abstract class AbstractNode extends java.lang.Object implements Node, java.io.Serializable
Page
, the
starting and ending position in the page, the parent and the list of
children
.Modifier and Type | Field and Description |
---|---|
protected NodeList |
children
The children of this node.
|
protected Page |
mPage
The page this node came from.
|
protected int |
nodeBegin
The beginning position of the tag in the line
|
protected int |
nodeEnd
The ending position of the tag in the line
|
protected Node |
parent
The parent of this node.
|
Constructor and Description |
---|
AbstractNode(Page page,
int start,
int end)
Create an abstract node with the page positions given.
|
Modifier and Type | Method and Description |
---|---|
abstract void |
accept(NodeVisitor visitor)
Visit this node.
|
java.lang.Object |
clone()
Clone this object.
|
void |
collectInto(NodeList list,
NodeFilter filter)
Collect this node and its child nodes (if-applicable) into the collectionList parameter, provided the node
satisfies the filtering criteria.
|
void |
doSemanticAction()
Perform the meaning of this tag.
|
NodeList |
getChildren()
Get the children of this node.
|
int |
getEndPosition()
Gets the ending position of the node.
|
Page |
getPage()
Get the page this node came from.
|
Node |
getParent()
Get the parent of this node.
|
int |
getStartPosition()
Gets the starting position of the node.
|
java.lang.String |
getText()
Returns the text of the node.
|
void |
setChildren(NodeList children)
Set the children of this node.
|
void |
setEndPosition(int position)
Sets the ending position of the node.
|
void |
setPage(Page page)
Set the page this node came from.
|
void |
setParent(Node node)
Sets the parent of this node.
|
void |
setStartPosition(int position)
Sets the starting position of the node.
|
void |
setText(java.lang.String text)
Sets the string contents of the node.
|
abstract java.lang.String |
toHtml()
Return the HTML that generated this node.
|
abstract java.lang.String |
toPlainTextString()
Returns a string representation of the node.
|
abstract java.lang.String |
toString()
Return a string representation of the node.
|
protected Page mPage
protected int nodeBegin
protected int nodeEnd
protected Node parent
protected NodeList children
public AbstractNode(Page page, int start, int end)
page
- The page this tag was read from.start
- The starting offset of this node within the page.end
- The ending offset of this node within the page.public java.lang.Object clone() throws java.lang.CloneNotSupportedException
public abstract java.lang.String toPlainTextString()
Node node; for (Enumeration e = parser.elements (); e.hasMoreElements (); ) { node = (Node)e.nextElement(); System.out.println (node.toPlainTextString ()); // or do whatever processing you wish with the plain text string }
toPlainTextString
in interface Node
public abstract java.lang.String toHtml()
public abstract java.lang.String toString()
System.out.println(node)
public void collectInto(NodeList list, NodeFilter filter)
This mechanism allows powerful filtering code to be written very easily,
without bothering about collection of embedded tags separately.
e.g. when we try to get all the links on a page, it is not possible to
get it at the top-level, as many tags (like form tags), can contain
links embedded in them. We could get the links out by checking if the
current node is a CompositeTag
, and going through its children.
So this method provides a convenient way to do this.
Using collectInto(), programs get a lot shorter. Now, the code to extract all links from a page would look like:
NodeList collectionList = new NodeList(); NodeFilter filter = new TagNameFilter ("A"); for (NodeIterator e = parser.elements(); e.hasMoreNodes();) e.nextNode().collectInto(collectionList, filter);Thus, collectionList will hold all the link nodes, irrespective of how deep the links are embedded.
Another way to accomplish the same objective is:
NodeList collectionList = new NodeList(); NodeFilter filter = new TagClassFilter (LinkTag.class); for (NodeIterator e = parser.elements(); e.hasMoreNodes();) e.nextNode().collectInto(collectionList, filter);This is slightly less specific because the LinkTag class may be registered for more than one node name, e.g. <LINK> tags too.
collectInto
in interface Node
list
- The node list to collect acceptable nodes into.filter
- The filter to determine which nodes are retained.public Page getPage()
public void setPage(Page page)
public int getStartPosition()
getStartPosition
in interface Node
public void setStartPosition(int position)
setStartPosition
in interface Node
position
- The new start position.public int getEndPosition()
getEndPosition
in interface Node
public void setEndPosition(int position)
setEndPosition
in interface Node
position
- The new end position.public abstract void accept(NodeVisitor visitor)
public Node getParent()
CompositeTag
.public void setParent(Node node)
public NodeList getChildren()
getChildren
in interface Node
null
otherwise.public void setChildren(NodeList children)
setChildren
in interface Node
children
- The new list of children this node contains.public java.lang.String getText()
public void setText(java.lang.String text)
public void doSemanticAction() throws ParserException
doSemanticAction
in interface Node
ParserException
- Not used. Provides for subclasses
that may want to indicate an exceptional condition.HTML Parser is an open source library released under LGPL.