Elements
package org.jsoup.select;
import org.jsoup.helper.Validate;
import org.jsoup.nodes.Element;
import org.jsoup.nodes.FormElement;
import org.jsoup.nodes.Node;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.List;
/**
A list of {@link Element}s, with methods that act on every element in the list.
<p>
To get an {@code Elements} object, use the {@link Element#select(String)} method.
</p>
@author Jonathan Hedley, [email protected] */
public class Elements extends ArrayList<Element> {
public Elements() {
}
public Elements(int initialCapacity) {
super(initialCapacity);
}
public Elements(Collection<Element> elements) {
super(elements);
}
public Elements(List<Element> elements) {
super(elements);
}
public Elements(Element... elements) {
super(Arrays.asList(elements));
}
/**
* Creates a deep copy of these elements.
* @return a deep copy
*/
@Override
public Elements clone() {
Elements clone = new Elements(size());
for(Element e : this)
clone.add(e.clone());
return clone;
}
// attribute methods
/**
Get an attribute value from the first matched element that has the attribute.
@param attributeKey The attribute key.
@return The attribute value from the first matched element that has the attribute.. If no elements were matched (isEmpty() == true),
or if the no elements have the attribute, returns empty string.
@see #hasAttr(String)
*/
public String attr(String attributeKey) {
for (Element element : this) {
if (element.hasAttr(attributeKey))
return element.attr(attributeKey);
}
return "";
}
/**
Checks if any of the matched elements have this attribute defined.
@param attributeKey attribute key
@return true if any of the elements have the attribute; false if none do.
*/
public boolean hasAttr(String attributeKey) {
for (Element element : this) {
if (element.hasAttr(attributeKey))
return true;
}
return false;
}
/**
* Get the attribute value for each of the matched elements. If an element does not have this attribute, no value is
* included in the result set for that element.
* @param attributeKey the attribute name to return values for. You can add the {@code abs:} prefix to the key to
* get absolute URLs from relative URLs, e.g.: {@code doc.select("a").eachAttr("abs:href")} .
* @return a list of each element's attribute value for the attribute
*/
public List<String> eachAttr(String attributeKey) {
List<String> attrs = new ArrayList<>(size());
for (Element element : this) {
if (element.hasAttr(attributeKey))
attrs.add(element.attr(attributeKey));
}
return attrs;
}
/**
* Set an attribute on all matched elements.
* @param attributeKey attribute key
* @param attributeValue attribute value
* @return this
*/
public Elements attr(String attributeKey, String attributeValue) {
for (Element element : this) {
element.attr(attributeKey, attributeValue);
}
return this;
}
/**
* Remove an attribute from every matched element.
* @param attributeKey The attribute to remove.
* @return this (for chaining)
*/
public Elements removeAttr(String attributeKey) {
for (Element element : this) {
element.removeAttr(attributeKey);
}
return this;
}
/**
Add the class name to every matched element's {@code class} attribute.
@param className class name to add
@return this
*/
public Elements addClass(String className) {
for (Element element : this) {
element.addClass(className);
}
return this;
}
/**
Remove the class name from every matched element's {@code class} attribute, if present.
@param className class name to remove
@return this
*/
public Elements removeClass(String className) {
for (Element element : this) {
element.removeClass(className);
}
return this;
}
/**
Toggle the class name on every matched element's {@code class} attribute.
@param className class name to add if missing, or remove if present, from every element.
@return this
*/
public Elements toggleClass(String className) {
for (Element element : this) {
element.toggleClass(className);
}
return this;
}
/**
Determine if any of the matched elements have this class name set in their {@code class} attribute.
@param className class name to check for
@return true if any do, false if none do
*/
public boolean hasClass(String className) {
for (Element element : this) {
if (element.hasClass(className))
return true;
}
return false;
}
/**
* Get the form element's value of the first matched element.
* @return The form element's value, or empty if not set.
* @see Element#val()
*/
public String val() {
if (size() > 0)
return first().val();
else
return "";
}
/**
* Set the form element's value in each of the matched elements.
* @param value The value to set into each matched element
* @return this (for chaining)
*/
public Elements val(String value) {
for (Element element : this)
element.val(value);
return this;
}
/**
* Get the combined text of all the matched elements.
* <p>
* Note that it is possible to get repeats if the matched elements contain both parent elements and their own
* children, as the Element.text() method returns the combined text of a parent and all its children.
* @return string of all text: unescaped and no HTML.
* @see Element#text()
* @see #eachText()
*/
public String text() {
StringBuilder sb = new StringBuilder();
for (Element element : this) {
if (sb.length() != 0)
sb.append(" ");
sb.append(element.text());
}
return sb.toString();
}
/**
Test if any matched Element has any text content, that is not just whitespace.
@return true if any element has non-blank text content.
@see Element#hasText()
*/
public boolean hasText() {
for (Element element: this) {
if (element.hasText())
return true;
}
return false;
}
/**
* Get the text content of each of the matched elements. If an element has no text, then it is not included in the
* result.
* @return A list of each matched element's text content.
* @see Element#text()
* @see Element#hasText()
* @see #text()
*/
public List<String> eachText() {
ArrayList<String> texts = new ArrayList<>(size());
for (Element el: this) {
if (el.hasText())
texts.add(el.text());
}
return texts;
}
/**
* Get the combined inner HTML of all matched elements.
* @return string of all element's inner HTML.
* @see #text()
* @see #outerHtml()
*/
public String html() {
StringBuilder sb = new StringBuilder();
for (Element element : this) {
if (sb.length() != 0)
sb.append("\n");
sb.append(element.html());
}
return sb.toString();
}
/**
* Get the combined outer HTML of all matched elements.
* @return string of all element's outer HTML.
* @see #text()
* @see #html()
*/
public String outerHtml() {
StringBuilder sb = new StringBuilder();
for (Element element : this) {
if (sb.length() != 0)
sb.append("\n");
sb.append(element.outerHtml());
}
return sb.toString();
}
/**
* Get the combined outer HTML of all matched elements. Alias of {@link #outerHtml()}.
* @return string of all element's outer HTML.
* @see #text()
* @see #html()
*/
@Override
public String toString() {
return outerHtml();
}
/**
* Update the tag name of each matched element. For example, to change each {@code <i>} to a {@code <em>}, do
* {@code doc.select("i").tagName("em");}
* @param tagName the new tag name
* @return this, for chaining
* @see Element#tagName(String)
*/
public Elements tagName(String tagName) {
for (Element element : this) {
element.tagName(tagName);
}
return this;
}
/**
* Set the inner HTML of each matched element.
* @param html HTML to parse and set into each matched element.
* @return this, for chaining
* @see Element#html(String)
*/
public Elements html(String html) {
for (Element element : this) {
element.html(html);
}
return this;
}
/**
* Add the supplied HTML to the start of each matched element's inner HTML.
* @param html HTML to add inside each element, before the existing HTML
* @return this, for chaining
* @see Element#prepend(String)
*/
public Elements prepend(String html) {
for (Element element : this) {
element.prepend(html);
}
return this;
}
/**
* Add the supplied HTML to the end of each matched element's inner HTML.
* @param html HTML to add inside each element, after the existing HTML
* @return this, for chaining
* @see Element#append(String)
*/
public Elements append(String html) {
for (Element element : this) {
element.append(html);
}
return this;
}
/**
* Insert the supplied HTML before each matched element's outer HTML.
* @param html HTML to insert before each element
* @return this, for chaining
* @see Element#before(String)
*/
public Elements before(String html) {
for (Element element : this) {
element.before(html);
}
return this;
}
/**
* Insert the supplied HTML after each matched element's outer HTML.
* @param html HTML to insert after each element
* @return this, for chaining
* @see Element#after(String)
*/
public Elements after(String html) {
for (Element element : this) {
element.after(html);
}
return this;
}
/**
Wrap the supplied HTML around each matched elements. For example, with HTML
{@code <p><b>This</b> is <b>Jsoup</b></p>},
<code>doc.select("b").wrap("<i></i>");</code>
becomes {@code <p><i><b>This</b></i> is <i><b>jsoup</b></i></p>}
@param html HTML to wrap around each element, e.g. {@code <div class="head"></div>}. Can be arbitrarily deep.
@return this (for chaining)
@see Element#wrap
*/
public Elements wrap(String html) {
Validate.notEmpty(html);
for (Element element : this) {
element.wrap(html);
}
return this;
}
/**
* Removes the matched elements from the DOM, and moves their children up into their parents. This has the effect of
* dropping the elements but keeping their children.
* <p>
* This is useful for e.g removing unwanted formatting elements but keeping their contents.
* </p>
*
* E.g. with HTML: <p>{@code <div><font>One</font> <font><a href="/">Two</a></font></div>}</p>
* <p>{@code doc.select("font").unwrap();}</p>
* <p>HTML = {@code <div>One <a href="/">Two</a></div>}</p>
*
* @return this (for chaining)
* @see Node#unwrap
*/
public Elements unwrap() {
for (Element element : this) {
element.unwrap();
}
return this;
}
/**
* Empty (remove all child nodes from) each matched element. This is similar to setting the inner HTML of each
* element to nothing.
* <p>
* E.g. HTML: {@code <div><p>Hello <b>there</b></p> <p>now</p></div>}<br>
* <code>doc.select("p").empty();</code><br>
* HTML = {@code <div><p></p> <p></p></div>}
* @return this, for chaining
* @see Element#empty()
* @see #remove()
*/
public Elements empty() {
for (Element element : this) {
element.empty();
}
return this;
}
/**
* Remove each matched element from the DOM. This is similar to setting the outer HTML of each element to nothing.
* <p>
* E.g. HTML: {@code <div><p>Hello</p> <p>there</p> <img /></div>}<br>
* <code>doc.select("p").remove();</code><br>
* HTML = {@code <div> <img /></div>}
* <p>
* Note that this method should not be used to clean user-submitted HTML; rather, use {@link org.jsoup.safety.Cleaner} to clean HTML.
* @return this, for chaining
* @see Element#empty()
* @see #empty()
*/
public Elements remove() {
for (Element element : this) {
element.remove();
}
return this;
}
// filters
/**
* Find matching elements within this element list.
* @param query A {@link Selector} query
* @return the filtered list of elements, or an empty list if none match.
*/
public Elements select(String query) {
return Selector.select(query, this);
}
/**
* Remove elements from this list that match the {@link Selector} query.
* <p>
* E.g. HTML: {@code <div class=logo>One</div> <div>Two</div>}<br>
* <code>Elements divs = doc.select("div").not(".logo");</code><br>
* Result: {@code divs: [<div>Two</div>]}
* <p>
* @param query the selector query whose results should be removed from these elements
* @return a new elements list that contains only the filtered results
*/
public Elements not(String query) {
Elements out = Selector.select(query, this);
return Selector.filterOut(this, out);
}
/**
* Get the <i>nth</i> matched element as an Elements object.
* <p>
* See also {@link #get(int)} to retrieve an Element.
* @param index the (zero-based) index of the element in the list to retain
* @return Elements containing only the specified element, or, if that element did not exist, an empty list.
*/
public Elements eq(int index) {
return size() > index ? new Elements(get(index)) : new Elements();
}
/**
* Test if any of the matched elements match the supplied query.
* @param query A selector
* @return true if at least one element in the list matches the query.
*/
public boolean is(String query) {
Evaluator eval = QueryParser.parse(query);
for (Element e : this) {
if (e.is(eval))
return true;
}
return false;
}
/**
* Get the immediate next element sibling of each element in this list.
* @return next element siblings.
*/
public Elements next() {
return siblings(null, true, false);
}
/**
* Get the immediate next element sibling of each element in this list, filtered by the query.
* @param query CSS query to match siblings against
* @return next element siblings.
*/
public Elements next(String query) {
return siblings(query, true, false);
}
/**
* Get all of the following element siblings of each element in this list.
* @return all following element siblings.
*/
public Elements nextAll() {
return siblings(null, true, true);
}
/**
* Get all of the following element siblings of each element in this list, filtered by the query.
* @param query CSS query to match siblings against
* @return all following element siblings.
*/
public Elements nextAll(String query) {
return siblings(query, true, true);
}
/**
* Get the immediate previous element sibling of each element in this list.
* @return previous element siblings.
*/
public Elements prev() {
return siblings(null, false, false);
}
/**
* Get the immediate previous element sibling of each element in this list, filtered by the query.
* @param query CSS query to match siblings against
* @return previous element siblings.
*/
public Elements prev(String query) {
return siblings(query, false, false);
}
/**
* Get all of the previous element siblings of each element in this list.
* @return all previous element siblings.
*/
public Elements prevAll() {
return siblings(null, false, true);
}
/**
* Get all of the previous element siblings of each element in this list, filtered by the query.
* @param query CSS query to match siblings against
* @return all previous element siblings.
*/
public Elements prevAll(String query) {
return siblings(query, false, true);
}
private Elements siblings(String query, boolean next, boolean all) {
Elements els = new Elements();
Evaluator eval = query != null? QueryParser.parse(query) : null;
for (Element e : this) {
do {
Element sib = next ? e.nextElementSibling() : e.previousElementSibling();
if (sib == null) break;
if (eval == null)
els.add(sib);
else if (sib.is(eval))
els.add(sib);
e = sib;
} while (all);
}
return els;
}
/**
* Get all of the parents and ancestor elements of the matched elements.
* @return all of the parents and ancestor elements of the matched elements
*/
public Elements parents() {
HashSet<Element> combo = new LinkedHashSet<>();
for (Element e: this) {
combo.addAll(e.parents());
}
return new Elements(combo);
}
// list-like methods
/**
Get the first matched element.
@return The first matched element, or <code>null</code> if contents is empty.
*/
public Element first() {
return isEmpty() ? null : get(0);
}
/**
Get the last matched element.
@return The last matched element, or <code>null</code> if contents is empty.
*/
public Element last() {
return isEmpty() ? null : get(size() - 1);
}
/**
* Perform a depth-first traversal on each of the selected elements.
* @param nodeVisitor the visitor callbacks to perform on each node
* @return this, for chaining
*/
public Elements traverse(NodeVisitor nodeVisitor) {
NodeTraversor.traverse(nodeVisitor, this);
return this;
}
/**
* Perform a depth-first filtering on each of the selected elements.
* @param nodeFilter the filter callbacks to perform on each node
* @return this, for chaining
*/
public Elements filter(NodeFilter nodeFilter) {
NodeTraversor.filter(nodeFilter, this);
return this;
}
/**
* Get the {@link FormElement} forms from the selected elements, if any.
* @return a list of {@link FormElement}s pulled from the matched elements. The list will be empty if the elements contain
* no forms.
*/
public List<FormElement> forms() {
ArrayList<FormElement> forms = new ArrayList<>();
for (Element el: this)
if (el instanceof FormElement)
forms.add((FormElement) el);
return forms;
}
}
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标签：Elements,return,Element,element,public,matched From： https://www.cnblogs.com/herd/p/16268424.html