Use the ATTOPARSER framework to develop Java libraries
Use the ATTOPARSER framework to develop Java libraries
Overview:
Attoparser is a Java class library for parsing HTML and XML documents.It provides a simple and efficient way to process HTML and XML documents and extract useful information from it.Using ATTOPARSER, developers can quickly build their own network crawlers, information extraction tools, and data processing programs.
Introduction:
Attoparser uses an event -driven model to customize the callback function to handle various events in the analysis process.It provides a set of flexible and easy -to -use APIs that allow developers to easily analyze the labels, attributes and contents in HTML and XML documents.
The example code of the HTML document with Attoparser is as follows:
First, we need to add the dependency item of Attoparser.In the Maven project, the following dependencies can be added to the POM.XML file:
<dependency>
<groupId>org.attoparser</groupId>
<artifactId>attoparser</artifactId>
<version>2.0.2</version>
</dependency>
Then, we can create an HTML resolution instance and define the corresponding callback function to handle various HTML tags and content:
import org.attoparser.MarkupParser;
import org.attoparser.ParseException;
import org.attoparser.dom.Document;
import org.attoparser.dom.Tag;
import org.attoparser.dom.Text;
import java.util.List;
public class HtmlParser {
public static void main(String[] args) throws ParseException {
String html = "<html><body><h1>Title</h1><p>Paragraph</p></body></html>";
MarkupParser parser = new MarkupParser();
Document document = parser.parse(html);
processElement(document.getRootElement(), 0);
}
private static void processElement(Tag tag, int level) {
System.out.println(getIndentation(level) + "[" + tag.getElementCompleteName() + "]");
List<Tag> children = tag.getChildren();
for (Tag child : children) {
if (child instanceof Text) {
String text = ((Text) child).getContent();
System.out.println(getIndentation(level + 1) + text);
} else if (child instanceof Tag) {
processElement((Tag) child, level + 1);
}
}
}
private static String getIndentation(int level) {
StringBuilder indentation = new StringBuilder();
for (int i = 0; i < level; i++) {
indentation.append("\t");
}
return indentation.toString();
}
}
Run the above code, the output result is as follows:
[html]
\t[body]
\t\t[h1]
\t\t\tTitle
\t\t[p]
\t\t\tParagraph
In this example, we first created a HTML string, and then created a MarkupParser instance and passed the HTML string to it.Then, we define the processlement () method to recursively process the labels and content in the HTML document, and reduce the printing according to their levels.
Attoparser's advantage:
1. High performance: Attoparser uses an efficient analysis algorithm that can quickly analyze large HTML and XML documents.
2. Easy -to -use: ATTOPARSER's API design is simple and clear, easy to learn and use.
3. Powerful and flexible: Attoparser provides a series of callback functions that enable developers to customize behaviors in the process of analysis and meet different application needs.
4. Support HTML5 and XML: ATTOPARSER can analyze HTML5 and XML documents, and handle the labels and content as needed.
Summarize:
Attoparser is a powerful and flexible Java class library for parsing HTML and XML documents.It provides a simple and efficient way to handle information extraction and data processing tasks in Web.Regardless of whether to build a network crawler, developing data processing procedures, or automation test script, ATTOPARSER is an indispensable tool.I hope this article can help you understand and start using Attoparser for Java library development.
