Use the HTMLPARSER framework to analyze the HTML content in the Java class library
Use the HTMLPARSER framework to analyze the HTML content in the Java class library
Overview:
In Java applications, analysis of HTML content is a common task.To analyze and extract the data in the HTML document, the existing Java library can be used.This article will introduce how to use the HTMLPARSER framework to resolve the HTML content in the Java class library and provide some related Java code examples.
Introduction to HTMLPARSER framework
HTMLPARSER is an open source Java class library for analysis and processing HTML documents.It provides a set of APIs that are easy to use to extract information such as elements, attributes and texts in HTML documents.
Second, the installation and configuration of the HTMLPARSER framework
To use the HTMLPARSER framework, we need to add it to the dependence of the Java project.You can add HTMLPARSER to the project dependencies through the following Maven configuration:
<dependency>
<groupId>nu.validator.htmlparser</groupId>
<artifactId>htmlparser</artifactId>
<version>1.6.2</version>
</dependency>
Third, use HTMLPARSER to analyze HTML content
The following is an example code that shows how to use the HTMLPARSER framework to analyze the HTML content in the Java class library:
import org.htmlparser.Parser;
import org.htmlparser.filters.TagNameFilter;
import org.htmlparser.util.NodeList;
import org.htmlparser.util.ParserException;
import org.htmlparser.util.ParserUtils;
public class HtmlParserExample {
public static void main(String[] args) {
// html content
String htmlcontent = "<html> <head> <Title> sample page </title> </head> <body> </h1> <p> paragraph </p> </body> </html>";
try {
// Create a parster
Parser parser = new Parser();
// Set the html content of the parser
parser.setInputHTML(htmlContent);
// Filter, used to choose a specified label
TagNameFilter filter = new TagNameFilter("p");
// Get the filtered HTML element
NodeList nodeList = parser.parse(filter);
// Output extraction text content
System.out.println ("Extracted text content:");
for (int i = 0; i < nodeList.size(); i++) {
System.out.println(nodeList.elementAt(i).toPlainTextString());
}
} catch (ParserException e) {
e.printStackTrace();
}
}
}
In the above code, a PARSER object is first created, and the HTML content to be parsed through the SetInputHtml () method.Next, select the specified `<p>` tag using the Tagnamefilter filter.Then, the PARSE () method is called to analyze the HTML content and obtain the filtered HTML element.Finally, through traversing the Nodelist object, you can get the extracted text content.
Fourth, summary
This article introduces the method of analyzing the HTML content in the Java library using the HTMLPARSER framework.By using the HTMLPARSER framework, you can easily extract the elements, attributes and texts in the HTML document.The above Java code example can be used as an entry guide to help readers quickly get started with the HTMLPARSER framework.I hope this article will help you!
