CLJ Tagsoup framework in the Java library (Guide to use the clj tagsoup framework in Java Class Libraares)
CLJ tagsoup framework in the Java library
introduce:
ClJ Tagsoup is a Java -based HTML parsing gay library, which aims to allow Java developers to more easily analyze and handle HTML documents.This article will introduce how to use the CLJ Tagsoup framework in the Java library and provide some related Java code examples.
Install ClJ tagsoup:
To use the ClJ Tagsoup in the Java project, you need to add it as a dependent item first.You can add the following dependencies to the project's construction file (such as Maven's Pom.xml or Gradle's Build.gradle):
Maven:
<dependency>
<groupId>org.ccil.cowan.tagsoup</groupId>
<artifactId>tagsoup</artifactId>
<version>1.2.1</version>
</dependency>
Gradle:
groovy
implementation 'org.ccil.cowan.tagsoup:tagsoup:1.2.1'
Initialize CLJ tagsoup:
Before using clj tagsoup, you need to create an org.ccil.cowan.tagsoup.parser instance.You can use the following code to complete the initialization:
import org.ccil.cowan.tagsoup.Parser;
Parser parser = new Parser();
Analyze HTML document:
Once you are initialized, you can use ClJ Tagsoup to resolve HTML documents.The following is a simple example that shows how to resolve HTML from the URL:
import org.ccil.cowan.tagsoup.Parser;
import org.xml.sax.InputSource;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
Parser parser = new Parser();
try {
URL url = new URL("https://example.com");
InputStreamReader reader = new InputStreamReader(url.openStream());
InputSource source = new InputSource(reader);
parser.parse(source);
} catch (IOException e) {
e.printStackTrace();
}
In this example, we use java.net.url to obtain HTML content from the specified URL, and use InputStreamReader and Inputsource to pass it to the PARSE method of CLJ TAGSOUP for analysis.
Processing analysis results:
Once the HTML document is successfully analyzed, you can use the method provided by the clj tagsoup to handle the analysis results.Here are some common operation examples:
Positioning element:
You can use the method provided by CLJ TAGSOUP to locate specific HTML elements.The following example demonstrates how to find all <a> label elements:
import org.ccil.cowan.tagsoup.Parser;
import org.ccil.cowan.tagsoup.TagSoupParser;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import java.io.IOException;
Parser parser = new Parser();
try {
URL url = new URL("https://example.com");
InputStreamReader reader = new InputStreamReader(url.openStream());
InputSource source = new InputSource(reader);
DefaultHandler handler = new DefaultHandler() {
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
if (qName.equalsIgnoreCase("a")) {
// Treat <a> tag elements
}
}
};
parser.setContentHandler(handler);
parser.parse(source);
} catch (IOException | SAXException e) {
e.printStackTrace();
}
In this example, we created an instance of DefaultHandler and check whether the label name (QName) of the element is "A" in the Startelement method to find all <a> tag elements.
Extract element content:
You can use the method provided by CLJ Tagsoup to extract the content of the HTML element.The following example demonstrates how to extract the text content in the <a> label:
import org.ccil.cowan.tagsoup.Parser;
import org.ccil.cowan.tagsoup.TagSoupParser;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import java.io.IOException;
Parser parser = new Parser();
try {
URL url = new URL("https://example.com");
InputStreamReader reader = new InputStreamReader(url.openStream());
InputSource source = new InputSource(reader);
DefaultHandler handler = new DefaultHandler() {
boolean insideTag = false;
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
if (qName.equalsIgnoreCase("a")) {
insideTag = true;
}
}
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
if (insideTag) {
String content = new String(ch, start, length);
// Treat the text content in the <a> label
}
}
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
if (qName.equalsIgnoreCase("a")) {
insideTag = false;
}
}
};
parser.setContentHandler(handler);
parser.parse(source);
} catch (IOException | SAXException e) {
e.printStackTrace();
}
In this example, we set up a logo position Insidetag in the Startelement method to indicate whether the currently label is inside the <a> label.Then, the text content surrounded by the label was extracted in the Characters method.
Summarize:
By using the CLJ Tagsoup framework, you can easily analyze and process HTML documents.This article provides a guidelines for CLJ TAGSOUP in the Java class library and gives some related Java code examples to help you start using this powerful HTML parsing library.I hope this information will be helpful to you, and I wish you successfully using CLJ TAGSOUP for Java development.
