org.dlese.dpc.util

Class HTMLParser

java.lang.Object

org.dlese.dpc.util.HTMLParser

public class HTMLParser
extends java.lang.Object

The HTMLParser class contains methods which allow an HTML document to be parsed. These methods allow text in the document to be extracted, as well as the contents of Meta tags Header (h1 , h2, h3, .. h6) tags, the Title tag, all the links in the page etc. Example html document at http://www.abc.org: (for help with explaining the methods in this API)

Welcome to ABC.ORG.

Hurricane season is here!

Whether directly affected or not, students can benefit from the engaging learning experiences these dramatic events can provide. Keep abreast of the current storm at the Tropical Prediction Center, where you can view advisories, maps and forecast tracks.

Middle school students can learn about hurricane science and safety with the Hurricane Strike module, while more advanced students can utilize the multimedia technology of the online meteorology guide Hurricanes.

One of ABC's newest collections, the NASA Scientific Visualization Studio, offers data, images and animations from previous Atlantic storms.

Author:

Sonal Bhushan

Constructor Summary

Constructors

Constructor and Description
HTMLParser(java.lang.String resourcelocn) Constructor of an HTMLParser object
HTMLParser(java.lang.String htmlcontent, java.lang.String charset) Constructor of an HTMLParser object

Method Summary

Modifier and Type	Method and Description
java.lang.String[]	getAllLinks() returns a String array of all the links in the html document.
java.lang.String	getHeaderText() returns all the text in the html page which is contained within header tags (which includes
java.lang.String	getImgAlts() returns a String containing all the text within the alt attribute of all the img tags in the html document
java.lang.String	getLinkTitles() returns a String containing all the text within the title attribute of all the links in the html document
java.lang.String	getMetaTagContentByName(java.lang.String name) returns the content of the Meta tag whose name equals mname.
java.lang.String	getTitleText() returns the title of the HTML page , i.e.
java.lang.String	getWholeText() returns the text of the whole html document, stripped of all the HTML tags.
boolean	hasMetaTagName(java.lang.String name) returns true if the html document contains a Meta tag with a name equal to mname , otherwise returns false e.g.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HTMLParser

public HTMLParser(java.lang.String resourcelocn)
           throws org.htmlparser.util.ParserException

Constructor of an HTMLParser object

Parameters:

resourcelocn - either a URL or the name of an HTML file

Throws:

org.htmlparser.util.ParserException - e.g.: HTMLParser hp = new HTMLParser("http://www.dlese.org"); HTMLParser hp2 = new HTMLParser(testthis.htm);

HTMLParser

public HTMLParser(java.lang.String htmlcontent,
                  java.lang.String charset)
           throws org.htmlparser.util.ParserException

Constructor of an HTMLParser object

Parameters:

htmlcontent - String containing the HTML to be parsed

charset - if null, the default encoding is used

Throws:

org.htmlparser.util.ParserException

Method Detail

getHeaderText

public java.lang.String getHeaderText()
                               throws org.htmlparser.util.ParserException

returns all the text in the html page which is contained within header tags (which includes

-

). If none of these tags are present in the page, it returns an empty string. e.g. : HTMLParser hp = new HTMLParser("http://www.abc.org"); System.out.println(hp.getHeaderText()); This prints out the following : Welcome to ABC.ORG Hurricane season is here!

Returns:

text in the header tags in the html document

Throws:

org.htmlparser.util.ParserException

getTitleText

public java.lang.String getTitleText()
                              throws org.htmlparser.util.ParserException

returns the title of the HTML page , i.e. the text enclosed by the tag. If this tag is not present in the page, it returns an empty string. e.g. : HTMLParserhp = new HTMLParser("http://www.abc.org"); System.out.println(hp.getTitleText()); This prints out the following : ABC.ORG's MAIN PAGE

Returns:

text in the title tag(s) in the html doc.

Throws:

org.htmlparser.util.ParserException

hasMetaTagName

public boolean hasMetaTagName(java.lang.String name)
                       throws org.htmlparser.util.ParserException

returns true if the html document contains a Meta tag with a name equal to mname , otherwise returns false e.g. : HTMLParser hp = new HTMLParser("http://www.abc.org"); boolean containskeywords = hp.hasMetaTagName("keywords"); boolean containsxyz = hp.hasMetaTagName("xyz"); In this code, containskeywords will be true, and containsxyz will be false.

Parameters:

name - name of the Meta Tag

Returns:

true or false, if this tag is present or not

Throws:

org.htmlparser.util.ParserException

getMetaTagContentByName

public java.lang.String getMetaTagContentByName(java.lang.String name)
                                         throws org.htmlparser.util.ParserException

returns the content of the Meta tag whose name equals mname. If such a tag does not exist, returns an empty string. E.g. : HTMLParser hp = new HTMLParser("http://www.abc.org"); if (hp.hasMetaTagName("organization")) { System.out.println(hp.getMetaTagContentByName("organization")); } This prints out the following : ABC Program Center

Parameters:

name - name of the Meta Tag

Returns:

The value of this meta tag

Throws:

org.htmlparser.util.ParserException

getAllLinks

public java.lang.String[] getAllLinks()
                               throws org.htmlparser.util.ParserException

returns a String array of all the links in the html document.

Returns:

a string array of all the links

Throws:

org.htmlparser.util.ParserException

getLinkTitles

public java.lang.String getLinkTitles()
                               throws org.htmlparser.util.ParserException

returns a String containing all the text within the title attribute of all the links in the html document

Returns:

all the text within the title attribute of all the links in the doc.

Throws:

org.htmlparser.util.ParserException

getImgAlts

public java.lang.String getImgAlts()
                            throws org.htmlparser.util.ParserException

returns a String containing all the text within the alt attribute of all the img tags in the html document

Returns:

all the text within the alt attribute of all the img tahs in the html doc

Throws:

org.htmlparser.util.ParserException

getWholeText

public java.lang.String getWholeText()
                              throws org.htmlparser.util.ParserException

returns the text of the whole html document, stripped of all the HTML tags. This text also includes the text within the alt attribute of all the img tags, as well as the text within the title attribute of all the link tags.

Returns:

The wholeText value

Throws:

org.htmlparser.util.ParserException