Class Segment

public Segment(Source source,
               int begin,
               int end)

Constructs a new Segment within the specified source document with the specified begin and end character positions.

Parameters:

source - the Source document, must not be null.

begin - the character position in the source where this segment begins, inclusive.

end - the character position in the source where this segment ends, exclusive.

public int compareTo(Object o)

Compares this Segment object to another object.

If the argument is not a Segment, a ClassCastException is thrown.

A segment is considered to be before another segment if its begin position is earlier, or in the case that both segments begin at the same position, its end position is earlier.

Segments that begin and end at the same position are considered equal for the purposes of this comparison, even if they relate to different source documents.

Note: this class has a natural ordering that is inconsistent with equals. This means that this method may return zero in some cases where calling the equals(Object) method with the same argument returns false.

Parameters:

o - the segment to be compared

Returns:

a negative integer, zero, or a positive integer as this segment is before, equal to, or after the specified segment.

public final boolean encloses(Segment segment)

Indicates whether this Segment encloses the specified Segment.

This is the case if getBegin()<=segment.getBegin() && getEnd()>=segment.getEnd().

Parameters:

segment - the segment to be tested for being enclosed by this segment.

Returns:

true if this Segment encloses the specified Segment, otherwise false.

public final boolean encloses(int pos)

Indicates whether this segment encloses the specified character position in the source document.

This is the case if getBegin() <= pos < getEnd().

Parameters:

pos - the position in the Source document.

Returns:

true if this segment encloses the specified character position in the source document, otherwise false.

public final boolean equals(Object object)

Compares the specified object with this Segment for equality.

Returns true if and only if the specified object is also a Segment, and both segments have the same Source, and the same begin and end positions.

Parameters:

object - the object to be compared for equality with this Segment.

Returns:

true if the specified object is equal to this Segment, otherwise false.

public String extractText()

Deprecated. Use getTextExtractor().toString() instead.

Extracts the textual content from the HTML markup of this segment.

This method has been deprecated as of version 2.4 and replaced with the getTextExtractor() method.

Returns:

the textual content from the HTML markup of this segment.

public String extractText(boolean includeAttributes)

Deprecated. Use getTextExtractor().setIncludeAttributes(includeAttributes).toString() instead.

Extracts the textual content from the HTML markup of this segment.

This method has been deprecated as of version 2.4 and replaced with the getTextExtractor() method.

Parameters:

includeAttributes - specifies whether the values of title, alt, label, and summary attributes are included in the output.

Returns:

the textual content from the HTML markup of this segment.

public List findAllCharacterReferences()

Returns a list of all CharacterReference objects that are enclosed by this segment.

Returns:

a list of all CharacterReference objects that are enclosed by this segment.

public List findAllElements()

Returns a list of all Element objects that are enclosed by this segment.

The Source.fullSequentialParse() method should be called after construction of the Source object if this method is to be used on a large proportion of the source. It is called automatically if this method is called on the Source object itself.

The elements returned correspond exactly with the start tags returned in the findAllStartTags() method.

Returns:

a list of all Element objects that are enclosed by this segment.

public List findAllElements(String name)

Returns a list of all Element objects with the specified name that are enclosed by this segment.

The elements returned correspond exactly with the start tags returned in the findAllStartTags(String name) method.

Specifying a null argument to the name parameter is equivalent to findAllElements().

This method also returns elements consisting of unregistered tags if the specified name is not a valid XML tag name.

Parameters:

name - the name of the elements to find.

Returns:

a list of all Element objects with the specified name that are enclosed by this segment.

public List findAllElements(String attributeName,
                            String value,
                            boolean valueCaseSensitive)

Returns a list of all Element objects with the specified attribute name/value pair that are enclosed by this segment.

The elements returned correspond exactly with the start tags returned in the findAllStartTags(String attributeName, String value, boolean valueCaseSensitive) method.

Parameters:

attributeName - the attribute name (case insensitive) to search for, must not be null.

value - the value of the specified attribute to search for, must not be null.

valueCaseSensitive - specifies whether the attribute value matching is case sensitive.

Returns:

a list of all Element objects with the specified attribute name/value pair that are enclosed by this segment.

public List findAllElements(StartTagType startTagType)

Returns a list of all Element objects with start tags of the specified type that are enclosed by this segment.

The elements returned correspond exactly with the start tags returned in the findAllTags(TagType) method.

Parameters:

startTagType - the type of start tags to find, must not be null.

Returns:

a list of all Element objects with start tags of the specified type that are enclosed by this segment.

public List findAllStartTags()

Returns a list of all StartTag objects that are enclosed by this segment.

The Source.fullSequentialParse() method should be called after construction of the Source object if this method is to be used on a large proportion of the source. It is called automatically if this method is called on the Source object itself.

See the Tag class documentation for more details about the behaviour of this method.

Returns:

a list of all StartTag objects that are enclosed by this segment.

public List findAllStartTags(String name)

Returns a list of all normal StartTag objects with the specified name that are enclosed by this segment.

See the Tag class documentation for more details about the behaviour of this method.

Specifying a null argument to the name parameter is equivalent to findAllStartTags().

This method also returns unregistered tags if the specified name is not a valid XML tag name.

Parameters:

name - the name of the start tags to find.

Returns:

a list of all normal StartTag objects with the specified name that are enclosed by this segment.

public List findAllStartTags(String attributeName,
                             String value,
                             boolean valueCaseSensitive)

Returns a list of all StartTag objects with the specified attribute name/value pair that are enclosed by this segment.

See the Tag class documentation for more details about the behaviour of this method.

Parameters:

attributeName - the attribute name (case insensitive) to search for, must not be null.

value - the value of the specified attribute to search for, must not be null.

valueCaseSensitive - specifies whether the attribute value matching is case sensitive.

Returns:

a list of all StartTag objects with the specified attribute name/value pair that are enclosed by this segment.

public List findAllTags()

Returns a list of all Tag objects that are enclosed by this segment.

The Source.fullSequentialParse() method should be called after construction of the Source object if this method is to be used on a large proportion of the source. It is called automatically if this method is called on the Source object itself.

See the Tag class documentation for more details about the behaviour of this method.

Returns:

a list of all Tag objects that are enclosed by this segment.

public List findAllTags(TagType tagType)

Returns a list of all Tag objects of the specified type that are enclosed by this segment.

See the Tag class documentation for more details about the behaviour of this method.

Specifying a null argument to the tagType parameter is equivalent to findAllTags().

Parameters:

tagType - the type of tags to find.

Returns:

a list of all Tag objects of the specified type that are enclosed by this segment.

public List findFormControls()

Returns a list of the FormControl objects that are enclosed by this segment.

Returns:

a list of the FormControl objects that are enclosed by this segment.

public FormFields findFormFields()

Returns the FormFields object representing all form fields that are enclosed by this segment.

This is equivalent to new FormFields(findFormControls()).

Returns:

the FormFields object representing all form fields that are enclosed by this segment.

See Also:

findFormControls()

public final int getBegin()

Returns the character position in the Source document at which this segment begins, inclusive.

Returns:

the character position in the Source document at which this segment begins, inclusive.

public List getChildElements()

Returns a list of the immediate children of this segment in the document element hierarchy.

The returned list may include an element that extends beyond the end of this segment, as long as it begins within this segment.

An element found at the start of this segment is included in the list. Note however that if this segment is an Element, the overriding Element.getChildElements() method is called instead, which only returns the children of the element.

Calling getChildElements() on an Element is usually more efficient than calling it on a Segment.

The objects in the list are all of type Element.

The Source.fullSequentialParse() method should be called after construction of the Source object if this method is to be used on a large proportion of the source. It is called automatically if this method is called on the Source object itself.

See the Source.getChildElements() method for more details.

Returns:

the a list of the immediate children of this segment in the document element hierarchy, guaranteed not null.

See Also:

Element.getParentElement()

public final int getEnd()

Returns the character position in the Source document immediately after the end of this segment.

The character at the position specified by this property is not included in the segment.

Returns:

the character position in the Source document immediately after the end of this segment.

public Iterator getNodeIterator()

Returns an iterator over every tag and text segment contained within this segment.

Every tag found in the findAllTags() list is included in this iterator, including all server tags.

Segments of the document between the tags are also included, resulting in a sequential walk-through of every "node" in this segment, where a node is either a tag or a segment of text. The end position of each segment should correspond with the begin position of the subsequent segment, unless any of the tags are enclosed by other tags, which is common when server tags are present.

The CharacterReference.decodeCollapseWhiteSpace(CharSequence) method can be used to retrieve the text from each text segment.

 for (Iterator nodeIterator=segment.getNoteIterator(); nodeIterator.hasNext();) {
   Segment nodeSegment=(Segment)nodeIterator.next();
   if (nodeSegment instanceof Tag) {
     Tag tag=(Tag)nodeSegment;
     if (tag.getTagType().isServerTag()) continue; // ignore server tags
     // Process the tag (just output it in this example):
     System.out.println(tag.tidy());
   } else {
     // Segment is a text segment.
     // Process the text segment (just output its text in this example):
     String text=CharacterReference.decodeCollapseWhiteSpace(nodeSegment);
     System.out.println(text);
   }
 }

Returns:

an iterator over every tag and text segment contained within this segment.

public Renderer getRenderer()

Performs a simple rendering of the HTML markup in this segment into text.

The output can be configured by setting any number of properties on the returned Renderer instance before obtaining its output.

Returns:

an instance of Renderer based on this segment.

See Also:

getTextExtractor()

public final Source getSource()

Returns the Source document containing this segment.

Returns:

the Source document containing this segment.

public TextExtractor getTextExtractor()

Extracts the textual content from the HTML markup of this segment.

The output can be configured by setting properties on the returned TextExtractor instance before obtaining its output.

Returns:

an instance of TextExtractor based on this segment.

See Also:

getRenderer()

public void ignoreWhenParsing()

Causes the this segment to be ignored when parsing.

Ignored segments are treated as blank spaces by the parsing mechanism, but are included as normal text in all other functions.

This method was originally the only means of preventing server tags located inside normal tags from interfering with the parsing of the tags (such as where an attribute of a normal tag uses a server tag to dynamically set its value), as well as preventing non-server tags from being recognised inside server tags.

As of version 2.4 it is no longer necessary to use this method to ignore server tags located inside normal tags, as the attributes parser now automatically ignores any server tags.

As of version 2.5 it is no longer necessary to use this method to ignore the contents of SCRIPT elements, as the parser now does this automatically when performing a full sequential parse.

As of version 2.6 is is no longer necessary to use this method to ignore non-server tags inside server tags, as the parser now does this automatically when performing a full sequential parse.

This leaves only very few scenarios where calling this method still provides a significant benefit.

One such case is where XML-style server tags are used inside normal tags. Here is an example using an XML-style JSP tag:

<a href="<i18n:resource path="/Portal"/>?BACK=TRUE">back</a>

The first double-quote of "/Portal" will be interpreted as the end quote for the href attribute, as there is no way for the parser to recognise the il8n:resource element as a server tag. Such use of XML-style server tags inside normal tags is generally seen as bad practice, but it is nevertheless valid JSP. The only way to ensure that this library is able to parse the normal tag surrounding it is to find these server tags first and call the ignoreWhenParsing method to ignore them before parsing the rest of the document.

It is important to understand the difference between ignoring the segment when parsing and removing the segment completely. Any text inside a segment that is ignored when parsing is treated by most functions as content, and as such is included in the output of tools such as TextExtractor and Renderer.

To remove segments completely, create an OutputDocument and call its remove(Segment) or replaceWithSpaces(int begin, int end) method for each segment. Then create a new source document using new Source(outputDocument.toString()) and perform the desired operations on this new source object.

Calling this method after the Source.fullSequentialParse() method has been called is not permitted and throws an IllegalStateException.

Any tags appearing in this segment that are found before this method is called will remain in the tag cache, and so will continue to be found by the tag search methods. If this is undesirable, the Source.clearCache() method can be called to remove them from the cache. Calling the Source.fullSequentialParse() method after this method clears the cache automatically.

For best performance, this method should be called on all segments that need to be ignored without calling any of the tag search methods in between.

See Also:

Source.ignoreWhenParsing(Collection segments)

public final boolean isWhiteSpace()

Indicates whether this segment consists entirely of white space.

Returns:

true if this segment consists entirely of white space, otherwise false.

public static final boolean isWhiteSpace(char ch)

Indicates whether the specified character is white space.

The HTML 4.01 specification section 9.1 specifies the following white space characters:

• space (U+0020)
• tab (U+0009)
• form feed (U+000C)
• line feed (U+000A)
• carriage return (U+000D)
• zero-width space (U+200B)

Despite the explicit inclusion of the zero-width space in the HTML specification, Microsoft IE6 does not recognise them as white space and renders them as an unprintable character (empty square). Even zero-width spaces included using the numeric character reference ​ are rendered this way.

Parameters:

ch - the character to test.

Returns:

true if the specified character is white space, otherwise false.

public Attributes parseAttributes()

Parses any Attributes within this segment. This method is only used in the unusual situation where attributes exist outside of a start tag. The StartTag.getAttributes() method should be used in normal situations.

This is equivalent to source.parseAttributes(getBegin(),getEnd()).

Returns:

the Attributes within this segment, or null if too many errors occur while parsing.

public String toString()

Returns the source text of this segment as a String.

The returned String is newly created with every call to this method, unless this segment is itself an instance of Source.

Note that before version 2.0 this returned a representation of this object useful for debugging purposes, which can now be obtained via the getDebugInfo() method.

Returns:

the source text of this segment as a String.