Node

所有超级接口:

java.lang.Cloneable

所有已知子接口:

Remark, Tag, Text

所有已知实现类:

AbstractNode, AppletTag, BaseHrefTag, BodyTag, Bullet, BulletList, CompositeTag, CompositeTagScannerTest.AnotherTag, CompositeTagScannerTest.CustomTag, DefinitionList, DefinitionListBullet, Div, DoctypeTag, FormTag, FrameSetTag, FrameTag, HeadingTag, HeadTag, Html, ImageTag, InputTag, JspTag, LabelTag, LinkTag, MetaTag, ObjectTag, OptionTag, ParagraphTag, ProcessingInstructionTag, RemarkNode, ScriptTag, SelectTag, SHTag, Span, StyleTag, TableColumn, TableHeader, TableRow, TableTag, TagNode, TextareaTag, TextNode, TitleTag, UlTag
```
public interface Node
extends java.lang.Cloneable
```
Specifies the minimum requirements for nodes returned by the Lexer or Parser. There are three types of nodes in HTML: text, remarks and tags. You may wish to define your own nodes to be returned by the Lexer or Parser, but each of the types must support this interface. More specific interface requirements for each of the node types are specified by the Text, Remark and Tag interfaces.

方法概要

所有方法实例方法抽象方法
限定符和类型	方法和说明
`void`	`accept(NodeVisitor visitor)` Apply the visitor to this node.
`java.lang.Object`	`clone()` Allow cloning of nodes.
`void`	`collectInto(NodeList list, NodeFilter filter)` Collect this node and its child nodes into a list, 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.
`Node`	`getFirstChild()` Get the first child of this node.
`Node`	`getLastChild()` Get the last child of this node.
`Node`	`getNextSibling()` Get the next sibling to this node.
`Page`	`getPage()` Get the page this node came from.
`Node`	`getParent()` Get the parent of this node.
`Node`	`getPreviousSibling()` Get the previous sibling to 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.
`java.lang.String`	`toHtml()` Return the HTML for this node.
`java.lang.String`	`toHtml(boolean verbatim)` Return the HTML for this node.
`java.lang.String`	`toPlainTextString()` A string representation of the node.
`java.lang.String`	`toString()` Return the string representation of the node.

- 方法详细资料
  - toPlainTextString
```
java.lang.String toPlainTextString()
```
    A string representation of the node. This is an important method, it allows a simple string transformation of a web page, regardless of a node. For a Text node this is obviously the textual contents itself. For a Remark node this is the remark contents (sic). For tags this is the text contents of it's children (if any). Because multiple nodes are combined when presenting a page in a browser, this will not reflect what a user would see. See HTML specification section 9.1 White space http://www.w3.org/TR/html4/struct/text.html#h-9.1.
    Typical application code (for extracting only the text from a web page) would be:
```
 for (Enumeration e = parser.elements (); e.hasMoreElements ();)
     // or do whatever processing you wish with the plain text string
     System.out.println ((Node)e.nextElement ()).toPlainTextString ());
 
```
    返回:
    
    The text of this node including it's children.
  - toHtml
```
java.lang.String toHtml()
```
    Return the HTML for this node. This should be the sequence of characters that were encountered by the parser that caused this node to be created. Where this breaks down is where broken nodes (tags and remarks) have been encountered and fixed. Applications reproducing html can use this method on nodes which are to be used or transferred as they were received or created.
    
    返回:
    
    The sequence of characters that would cause this node to be returned by the parser or lexer.
  - toHtml
```
java.lang.String toHtml(boolean verbatim)
```
    Return the HTML for this node. This should be the exact sequence of characters that were encountered by the parser that caused this node to be created. Where this breaks down is where broken nodes (tags and remarks) have been encountered and fixed. Applications reproducing html can use this method on nodes which are to be used or transferred as they were received or created.
    
    参数:
    
    verbatim - If true return as close to the original page text as possible.
    
    返回:
    
    The (exact) sequence of characters that would cause this node to be returned by the parser or lexer.
  - toString
```
java.lang.String toString()
```
    Return the string representation of the node. The return value may not be the entire contents of the node, and non- printable characters may be translated in order to make them visible. This is typically to be used in the manner
```
 System.out.println (node);
 
```
    or within a debugging environment.
    覆盖:
    
    toString 在类中 java.lang.Object
    
    返回:
    
    A string representation of this node suitable for printing, that isn't too large.
  - collectInto
```
void collectInto(NodeList list,
                 NodeFilter filter)
```
    Collect this node and its child nodes into a list, 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 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.
    参数:
    
    list - The list to collect nodes into.
    
    filter - The criteria to use when deciding if a node should be added to the list.
  - getStartPosition
```
int getStartPosition()
```
    Gets the starting position of the node. This is the character (not byte) offset of this node in the page.
    
    返回:
    
    The start position.
    
    另请参阅:
    
    setStartPosition(int)
  - setStartPosition
```
void setStartPosition(int position)
```
    Sets the starting position of the node.
    
    参数:
    
    position - The new start position.
    
    另请参阅:
    
    getStartPosition()
  - getEndPosition
```
int getEndPosition()
```
    Gets the ending position of the node. This is the character (not byte) offset of the character following this node in the page.
    
    返回:
    
    The end position.
    
    另请参阅:
    
    setEndPosition(int)
  - setEndPosition
```
void setEndPosition(int position)
```
    Sets the ending position of the node.
    
    参数:
    
    position - The new end position.
    
    另请参阅:
    
    getEndPosition()
  - getPage
```
Page getPage()
```
    Get the page this node came from.
    
    返回:
    
    The page that supplied this node.
    
    另请参阅:
    
    setPage(org.htmlparser.lexer.Page)
  - setPage
```
void setPage(Page page)
```
    Set the page this node came from.
    
    参数:
    
    page - The page that supplied this node.
    
    另请参阅:
    
    getPage()
  - accept
```
void accept(NodeVisitor visitor)
```
    Apply the visitor to this node.
    
    参数:
    
    visitor - The visitor to this node.
  - getParent
```
Node getParent()
```
    Get the parent of this node. This will always return null when parsing with the Lexer. Currently, the object returned from this method can be safely cast to a CompositeTag, but this behaviour should not be expected in the future.
    
    返回:
    
    The parent of this node, if it's been set, null otherwise.
    
    另请参阅:
    
    setParent(org.htmlparser.Node)
  - setParent
```
void setParent(Node node)
```
    Sets the parent of this node.
    
    参数:
    
    node - The node that contains this node.
    
    另请参阅:
    
    getParent()
  - getChildren
```
NodeList getChildren()
```
    Get the children of this node.
    
    返回:
    
    The list of children contained by this node, if it's been set, null otherwise.
    
    另请参阅:
    
    setChildren(org.htmlparser.util.NodeList)
  - setChildren
```
void setChildren(NodeList children)
```
    Set the children of this node.
    
    参数:
    
    children - The new list of children this node contains.
    
    另请参阅:
    
    getChildren()
  - getFirstChild
```
Node getFirstChild()
```
    Get the first child of this node.
    
    返回:
    
    The first child in the list of children contained by this node, null otherwise.
  - getLastChild
```
Node getLastChild()
```
    Get the last child of this node.
    
    返回:
    
    The last child in the list of children contained by this node, null otherwise.
  - getPreviousSibling
```
Node getPreviousSibling()
```
    Get the previous sibling to this node.
    
    返回:
    
    The previous sibling to this node if one exists, null otherwise.
  - getNextSibling
```
Node getNextSibling()
```
    Get the next sibling to this node.
    
    返回:
    
    The next sibling to this node if one exists, null otherwise.
  - getText
```
java.lang.String getText()
```
    Returns the text of the node.
    
    返回:
    
    The contents of the string or remark node, and in the case of a tag, the contents of the tag less the enclosing angle brackets.
    
    另请参阅:
    
    setText(java.lang.String)
  - setText
```
void setText(java.lang.String text)
```
    Sets the string contents of the node.
    
    参数:
    
    text - The new text for the node.
    
    另请参阅:
    
    getText()
  - doSemanticAction
```
void doSemanticAction()
               throws ParserException
```
    Perform the meaning of this tag. This is defined by the tag, for example the bold tag <B> may switch bold text on and off. Only a few tags have semantic meaning to the parser. These have to do with the character set to use (<META>) and the base URL to use (<BASE>). Other than that, the semantic meaning is up to the application and it's custom nodes.
    The semantic action is performed when the node has been parsed. For composite nodes (those that contain other nodes), the children will have already been parsed and will be available via getChildren().
    
    抛出:
    
    ParserException - If a problem is encountered performing the semantic action.
  - clone
```
java.lang.Object clone()
                throws java.lang.CloneNotSupportedException
```
    Allow cloning of nodes. Creates and returns a copy of this object. The precise meaning of "copy" may depend on the class of the object. The general intent is that, for any object x, the expression:
    x.clone() != x
    will be true, and that the expression:
    x.clone().getClass() == x.getClass()
    will be true, but these are not absolute requirements. While it is typically the case that:
    x.clone().equals(x)
    will be true, this is not an absolute requirement.
    By convention, the returned object should be obtained by calling super.clone. If a class and all of its superclasses (except Object) obey this convention, it will be the case that x.clone().getClass() == x.getClass().
    By convention, the object returned by this method should be independent of this object (which is being cloned). To achieve this independence, it may be necessary to modify one or more fields of the object returned by super.clone before returning it. Typically, this means copying any mutable objects that comprise the internal "deep structure" of the object being cloned and replacing the references to these objects with references to the copies. If a class contains only primitive fields or references to immutable objects, then it is usually the case that no fields in the object returned by super.clone need to be modified.
    The method clone for class Object performs a specific cloning operation. First, if the class of this object does not implement the interface Cloneable, then a CloneNotSupportedException is thrown. Note that all arrays are considered to implement the interface Cloneable. Otherwise, this method creates a new instance of the class of this object and initializes all its fields with exactly the contents of the corresponding fields of this object, as if by assignment; the contents of the fields are not themselves cloned. Thus, this method performs a "shallow copy" of this object, not a "deep copy" operation.
    The class Object does not itself implement the interface Cloneable, so calling the clone method on an object whose class is Object will result in throwing an exception at run time.
    返回:
    
    a clone of this instance.
    
    抛出:
    
    java.lang.CloneNotSupportedException - if the object's class does not support the Cloneable interface. Subclasses that override the clone method can also throw this exception to indicate that an instance cannot be cloned.
    
    另请参阅:
    
    Cloneable

接口 Node

方法概要

方法详细资料

toPlainTextString

toHtml

toHtml

toString

collectInto

getStartPosition

setStartPosition

getEndPosition

setEndPosition

getPage

setPage

accept

getParent

setParent

getChildren

setChildren

getFirstChild

getLastChild

getPreviousSibling

getNextSibling

getText

setText

doSemanticAction

clone