org.htmlparser.tags

Class CompositeTag

public class CompositeTag extends TagNode

The base class for tags that have an end tag. Provided extra accessors for the children above and beyond what the basic {@link Tag} provides. Also handles the conversion of it's children for the {@link #toHtml toHtml} method.
Field Summary
protected static CompositeTagScannermDefaultCompositeScanner
The default scanner for non-composite tags.
protected TagmEndTag
The tag that causes this tag to finish.
Constructor Summary
CompositeTag()
Create a composite tag.
Method Summary
voidaccept(NodeVisitor visitor)
Tag visiting code.
NodechildAt(int index)
Get child at given index
SimpleNodeIteratorchildren()
Get an iterator over the children of this node.
voidcollectInto(NodeList list, NodeFilter filter)
Collect this node and its child nodes (if-applicable) into the list parameter, provided the node satisfies the filtering criteria.
Text[]digupStringNode(String searchText)
Finds a text node, however embedded it might be, and returns it.
SimpleNodeIteratorelements()
Return the child tags as an iterator.
intfindPositionOf(String text)
Returns the node number of the first node containing the given text.
intfindPositionOf(String text, Locale locale)
Returns the node number of the first node containing the given text.
intfindPositionOf(Node searchNode)
Returns the node number of a child node given the node object.
NodegetChild(int index)
Get the child of this node at the given position.
intgetChildCount()
Return the number of child nodes in this tag.
Node[]getChildrenAsNodeArray()
Get the children as an array of Node objects.
StringgetChildrenHTML()
Return the HTML code for the children of this tag.
TaggetEndTag()
Get the end tag for this tag.
StringgetStringText()
Return the text between the start tag and the end tag.
StringgetText()
Return the text contained in this tag.
protected voidputChildrenInto(StringBuffer sb, boolean verbatim)
Add the textual contents of the children of this node to the buffer.
protected voidputEndTagInto(StringBuffer sb, boolean verbatim)
Add the textual contents of the end tag of this node to the buffer.
voidremoveChild(int i)
Remove the child at the position given.
TagsearchByName(String name)
Searches all children who for a name attribute.
NodeListsearchFor(String searchString)
Searches for all nodes whose text representation contains the search string.
NodeListsearchFor(String searchString, boolean caseSensitive)
Searches for all nodes whose text representation contains the search string.
NodeListsearchFor(String searchString, boolean caseSensitive, Locale locale)
Searches for all nodes whose text representation contains the search string.
NodeListsearchFor(Class classType, boolean recursive)
Collect all objects that are of a certain type Note that this will not check for parent types, and will not recurse through child tags
voidsetEndTag(Tag tag)
Set the end tag for this tag.
StringtoHtml(boolean verbatim)
Return this tag as HTML code.
StringtoPlainTextString()
Return the textual contents of this tag and it's children.
StringtoString()
Return a string representation of the contents of this tag, it's children and it's end tag suitable for debugging.
voidtoString(int level, StringBuffer buffer)
Return a string representation of the contents of this tag, it's children and it's end tag suitable for debugging.

Field Detail

mDefaultCompositeScanner

protected static final CompositeTagScanner mDefaultCompositeScanner
The default scanner for non-composite tags.

mEndTag

protected Tag mEndTag
The tag that causes this tag to finish. May be a virtual tag generated by the scanning logic.

Constructor Detail

CompositeTag

public CompositeTag()
Create a composite tag.

Method Detail

accept

public void accept(NodeVisitor visitor)
Tag visiting code. Invokes accept() on the start tag and then walks the child list invoking accept() on each of the children, finishing up with an accept() call on the end tag. If shouldRecurseSelf() returns true it then asks the visitor to visit itself.

Parameters: visitor The NodeVisitor object to be signalled for each child and possibly this tag.

childAt

public Node childAt(int index)
Get child at given index

Parameters: index The index into the child node list.

Returns: Node The child node at the given index or null if none.

children

public SimpleNodeIterator children()
Get an iterator over the children of this node.

Returns: Am iterator over the children of this node.

collectInto

public void collectInto(NodeList list, NodeFilter filter)
Collect this node and its child nodes (if-applicable) into the list parameter, provided the node satisfies the filtering criteria.

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 {@link 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 list = new NodeList();
 NodeFilter filter = new TagNameFilter ("A");
 for (NodeIterator e = parser.elements(); e.hasMoreNodes();)
      e.nextNode().collectInto(list, filter);
 
Thus, list will hold all the link nodes, irrespective of how deep the links are embedded.

Another way to accomplish the same objective is:

 NodeList list = new NodeList();
 NodeFilter filter = new TagClassFilter (LinkTag.class);
 for (NodeIterator e = parser.elements(); e.hasMoreNodes();)
      e.nextNode().collectInto(list, filter);
 
This is slightly less specific because the LinkTag class may be registered for more than one node name, e.g. <LINK> tags too.

Parameters: list The list to add nodes to. filter The filter to apply.

See Also: org.htmlparser.filters

digupStringNode

public Text[] digupStringNode(String searchText)
Finds a text node, however embedded it might be, and returns it. The text node will retain links to its parents, so further navigation is possible.

Parameters: searchText The text to search for.

Returns: The list of text nodes (recursively) found.

elements

public SimpleNodeIterator elements()
Return the child tags as an iterator. Equivalent to calling getChildren ().elements ().

Returns: An iterator over the children.

findPositionOf

public int findPositionOf(String text)
Returns the node number of the first node containing the given text. This can be useful to index into the composite tag and get other children. Text is compared without case sensitivity and conversion to uppercase uses an English locale.

Parameters: text The text to search for.

Returns: int The node index in the children list of the node containing the text or -1 if not found.

See Also: CompositeTag

findPositionOf

public int findPositionOf(String text, Locale locale)
Returns the node number of the first node containing the given text. This can be useful to index into the composite tag and get other children. Text is compared without case sensitivity and conversion to uppercase uses the supplied locale.

Parameters: locale The locale to use in converting to uppercase. text The text to search for.

Returns: int The node index in the children list of the node containing the text or -1 if not found.

findPositionOf

public int findPositionOf(Node searchNode)
Returns the node number of a child node given the node object. This would typically be used in conjuction with digUpStringNode, after which the string node's parent can be used to find the string node's position. Faster than calling findPositionOf(text) again. Note that the position is at a linear level alone - there is no recursion in this method.

Parameters: searchNode The child node to find.

Returns: The offset of the child tag or -1 if it was not found.

getChild

public Node getChild(int index)
Get the child of this node at the given position.

Parameters: index The in the node list of the child.

Returns: The child at that index.

getChildCount

public int getChildCount()
Return the number of child nodes in this tag.

Returns: The child node count.

getChildrenAsNodeArray

public Node[] getChildrenAsNodeArray()
Get the children as an array of Node objects.

Returns: The children in an array.

getChildrenHTML

public String getChildrenHTML()
Return the HTML code for the children of this tag.

Returns: A string with the HTML code for the contents of this tag.

getEndTag

public Tag getEndTag()
Get the end tag for this tag. For example, if the node is {@.html

getStringText

public String getStringText()
Return the text between the start tag and the end tag.

Returns: The contents of the CompositeTag.

getText

public String getText()
Return the text contained in this tag.

Returns: The complete contents of the tag (within the angle brackets).

putChildrenInto

protected void putChildrenInto(StringBuffer sb, boolean verbatim)
Add the textual contents of the children of this node to the buffer.

Parameters: verbatim If true return as close to the original page text as possible. sb The buffer to append to.

putEndTagInto

protected void putEndTagInto(StringBuffer sb, boolean verbatim)
Add the textual contents of the end tag of this node to the buffer.

Parameters: verbatim If true return as close to the original page text as possible. sb The buffer to append to.

removeChild

public void removeChild(int i)
Remove the child at the position given.

Parameters: i The index of the child to remove.

searchByName

public Tag searchByName(String name)
Searches all children who for a name attribute. Returns first match.

Parameters: name Attribute to match in tag

Returns: Tag Tag matching the name attribute

searchFor

public NodeList searchFor(String searchString)
Searches for all nodes whose text representation contains the search string. Collects all nodes containing the search string into a NodeList. This search is case-insensitive and the search string and the node text are converted to uppercase using an English locale. For example, if you wish to find any textareas in a form tag containing "hello world", the code would be: NodeList nodeList = formTag.searchFor("Hello World");

Parameters: searchString Search criterion.

Returns: A collection of nodes whose string contents or representation have the searchString in them.

searchFor

public NodeList searchFor(String searchString, boolean caseSensitive)
Searches for all nodes whose text representation contains the search string. Collects all nodes containing the search string into a NodeList. For example, if you wish to find any textareas in a form tag containing "hello world", the code would be: NodeList nodeList = formTag.searchFor("Hello World");

Parameters: searchString Search criterion. caseSensitive If true this search should be case sensitive. Otherwise, the search string and the node text are converted to uppercase using an English locale.

Returns: A collection of nodes whose string contents or representation have the searchString in them.

searchFor

public NodeList searchFor(String searchString, boolean caseSensitive, Locale locale)
Searches for all nodes whose text representation contains the search string. Collects all nodes containing the search string into a NodeList. For example, if you wish to find any textareas in a form tag containing "hello world", the code would be: NodeList nodeList = formTag.searchFor("Hello World");

Parameters: searchString Search criterion. caseSensitive If true this search should be case sensitive. Otherwise, the search string and the node text are converted to uppercase using the locale provided. locale The locale for uppercase conversion.

Returns: A collection of nodes whose string contents or representation have the searchString in them.

searchFor

public NodeList searchFor(Class classType, boolean recursive)
Collect all objects that are of a certain type Note that this will not check for parent types, and will not recurse through child tags

Parameters: classType The class to search for. recursive If true, recursively search through the children.

Returns: A list of children found.

setEndTag

public void setEndTag(Tag tag)
Set the end tag for this tag.

Parameters: tag The new end tag for this tag. Note: no checking is perfromed so you can generate bad HTML by setting the end tag with a name not equal to the name of the start tag, i.e. {@.html

toHtml

public String toHtml(boolean verbatim)
Return this tag as HTML code.

Parameters: verbatim If true return as close to the original page text as possible.

Returns: This tag and it's contents (children) and the end tag as HTML code.

toPlainTextString

public String toPlainTextString()
Return the textual contents of this tag and it's children.

Returns: The 'browser' text contents of this tag.

toString

public String toString()
Return a string representation of the contents of this tag, it's children and it's end tag suitable for debugging.

Returns: A textual representation of the tag.

toString

public void toString(int level, StringBuffer buffer)
Return a string representation of the contents of this tag, it's children and it's end tag suitable for debugging.

Parameters: level The indentation level to use. buffer The buffer to append to.

HTML Parser is an open source library released under LGPL. SourceForge.net