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JavaXT
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Element Class
package javaxt.html;
import javaxt.xml.DOM;
//******************************************************************************
//** HTML Element
//******************************************************************************
/**
* Used to represent a DOM element in an HTML document.
*
******************************************************************************/
public class Element {
private String nodeName;
private String attributes;
private String innerHTML;
private String outerHTML;
private Parser parser;
private boolean isClosed;
//**************************************************************************
//** Constructor
//**************************************************************************
/** @param outerHTML HTML used to define a tag (e.g. <div id="1">test</div>)
*/
public Element(String outerHTML) throws Exception {
this.outerHTML = outerHTML;
//Get position of the first whitespace character
int ws = -1;
for (int z=0; z<outerHTML.length(); z++){
char t = outerHTML.charAt(z);
if (isWhitespace(t)){
ws = z+1;
break;
}
}
//Get position of the first ">" character
int gt = Parser.findGT(0, outerHTML+" ");
if (gt==-1) throw new Exception("Invalid or unsupported html"); //includes html comments
gt++;
//Set nodeName and attributes
int endNode;
if (ws==-1){
endNode = gt-1;
attributes = "";
}
else{
if (gt<ws){
endNode = gt-1;
attributes = "";
}
else{
endNode = ws;
attributes = outerHTML.substring(endNode, gt-1).trim();
if (attributes.endsWith("/")) attributes = attributes.substring(0, attributes.length()-1).trim();
}
}
nodeName = outerHTML.substring(1, endNode);
if (nodeName.endsWith("/")) nodeName = nodeName.substring(0, nodeName.length()-1);
nodeName = nodeName.trim();
//Set innerHTML
innerHTML = outerHTML.substring(gt);
if (innerHTML.trim().length()>0){ //has inner html
int idx = innerHTML.lastIndexOf("</" + nodeName);
if (idx>-1){
innerHTML = innerHTML.substring(0, idx);
isClosed = true;
}
else{
isClosed = false;
}
}
else{ //no inner html
//Check if the tag is self enclosing (e.g. "<hr/>")
char c = outerHTML.charAt(gt-2); //character immediately before ">"
isClosed = c=='/';
}
}
//**************************************************************************
//** getName
//**************************************************************************
/** Returns the node name associated with the element
*/
public String getName(){
return nodeName;
}
//**************************************************************************
//** getAttributes
//**************************************************************************
/** Returns the element attributes
* @return Anything that appears after the tag/node name
*/
public String getAttributes(){
return attributes;
}
//**************************************************************************
//** isClosed
//**************************************************************************
/** Returns true if the element has a closing tag or is self closing
*/
public boolean isClosed(){
return isClosed;
}
//**************************************************************************
//** getInnerHTML
//**************************************************************************
/** Returns the HTML content (inner HTML) of an element as a String.
*/
public String getInnerHTML(){
return innerHTML;
}
//**************************************************************************
//** getOuterHTML
//**************************************************************************
/** Returns the HTML used to define this element (tag and attributes), as
* well as the HTML content (inner HTML). You can use this String to remove
* or replace elements from the original HTML document.
*/
public String getOuterHTML(){
return outerHTML;
}
//**************************************************************************
//** getInnerText
//**************************************************************************
/** Removes all HTML tags and attributes inside this element, leaving the
* raw rendered text.
*/
public String getInnerText(){
return Parser.stripHTMLTags(innerHTML);
}
//**************************************************************************
//** getAttribute
//**************************************************************************
/** Returns the value for a given attribute. If no match is found, returns
* an empty string.
*/
public String getAttribute(String attributeName){
return _getAttributeValue(attributeName);
}
//**************************************************************************
//** getElementByID
//**************************************************************************
/** Returns an HTML Element with given a id. Returns null if the element was
* not found.
*/
public Element getElementByID(String id){
return getElementByAttributes(null, "id", id);
}
//**************************************************************************
//** getElementByTagName
//**************************************************************************
/** Returns an array of HTML Elements with given tag name.
*/
public Element[] getElementsByTagName(String tagName){
return getParser().getElementsByTagName(tagName);
}
//**************************************************************************
//** getElementByTagName
//**************************************************************************
/** Returns the first HTML Element with given tag name. Returns null if an
* element was not found.
*/
public Element getElementByTagName(String tagName){
return getElementByAttributes(tagName, null, null);
}
//**************************************************************************
//** getElements
//**************************************************************************
public Element[] getChildNodes(){
return getParser().getElements();
}
//**************************************************************************
//** getElements
//**************************************************************************
/** Returns an array of HTML Elements with given tag name, attribute, and
* attribute value (e.g. "div", "class", "panel-header").
*/
public Element[] getElements(String tagName, String attributeName, String attributeValue){
return getParser().getElements(tagName, attributeName, attributeValue);
}
//**************************************************************************
//** getElementByAttributes
//**************************************************************************
/** Returns the first HTML Element with given tag name and attribute. Returns
* null if an element was not found.
*/
public Element getElementByAttributes(String tagName, String attributeName, String attributeValue){
return getParser().getElementByAttributes(tagName, attributeName, attributeValue);
}
//**************************************************************************
//** getImageLinks
//**************************************************************************
/** Returns a list of links to images. The links may include relative paths.
* Use the Parser.getAbsolutePath() method to resolve the relative paths to
* a fully qualified url.
*/
public String[] getImageLinks(){
return getParser().getImageLinks();
}
//**************************************************************************
//** getParser
//**************************************************************************
private Parser getParser(){
if (parser==null) parser = new Parser(innerHTML);
return parser;
}
//**************************************************************************
//** toString
//**************************************************************************
/** Returns the outer HTML of this element. See getOuterHTML() for more
* information.
*/
public String toString(){
return outerHTML;
}
/** @deprecated Use getInnerText() */
public String stripHTMLTags(){
return getInnerText();
}
/** @deprecated Use getAttribute() */
public String getAttributeValue(String attributeName){
return getAttribute(attributeName);
}
//**************************************************************************
//** getAttributeValue
//**************************************************************************
/** Returns the value for a given attribute. If no match is found, returns
* an empty string.
*/
private String _getAttributeValue(String attributeName){
String tag = (nodeName + " " + attributes).trim();
try{
org.w3c.dom.Document XMLDoc = DOM.createDocument("<" + tag + "/>");
org.w3c.dom.NamedNodeMap attr = XMLDoc.getFirstChild().getAttributes();
return DOM.getAttributeValue(attr,attributeName);
}
catch(Exception e){
try{
return _getAttributeValue2(tag, attributeName);
}
catch(Exception ex){
return "";
}
}
}
private String _getAttributeValue2(String tag, String attributeName){
tag = tag.trim();
if (!tag.contains(" ")) return tag;
String orgTag = tag;
tag = tag.substring(tag.indexOf(" "), tag.length()).trim();
String tagName = orgTag + " ";
tagName = tagName.substring(0, tagName.indexOf(" "));
//compress spaces
String newTag = "";
tag += " ";
for (int i=0; i<tag.length()-1; i++){
char ch = tag.charAt(i);
if (ch==' ' && tag.charAt(i+1)==' '){
}
else{
newTag += ch;
}
}
newTag = newTag.replace("= ", "=");
newTag = newTag.replace(" =", "=");
//System.out.println("newTag = " + newTag);System.out.println();
newTag = " " + newTag + " ";
//attributeName = attributeName.toLowerCase();
for (int i=0; i<newTag.length(); i++){
char ch = newTag.charAt(i);
if (ch == '='){
String tmp = newTag.substring(0, i);
//System.out.println(tmp);
String AttrName = tmp.substring(tmp.lastIndexOf(" "), tmp.length()).trim();
String AttrValue = "";
//System.out.println("AttrName = " + AttrName);
if (AttrName.equalsIgnoreCase(attributeName)){
tmp = newTag.substring(i+1, newTag.length()).trim() + " ";
if (newTag.charAt(i+1)=='"'){
tmp = tmp.substring(1, tmp.length());
AttrValue = tmp.substring(0, tmp.indexOf("\""));
}
else if (newTag.charAt(i+1)=='\''){
tmp = tmp.substring(1, tmp.length());
AttrValue = tmp.substring(0, tmp.indexOf("'"));
}
else{
AttrValue = tmp.substring(0, tmp.indexOf(" "));
}
return AttrValue;
}
}
}
return "";
}
//**************************************************************************
//** isWhitespace
//**************************************************************************
/** Returns true if the given char is a white space, tab or return
*/
private static boolean isWhitespace(char c){
if (c==' ') return true;
if (c=='\r') return true;
if (c=='\n') return true;
if (c=='\t') return true;
return false;
}
}
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