Detailed explanation of the technical principles of Apache Commons Digester framework in the Java class library

Apache Commons Digest is a Java -based open source framework that is used to map the XML file to the Java object.It provides a simple and powerful way to analyze the XML document and convert it into an operable Java object, which simplifies the task of developers when processing XML data. The core principle of the DIGESTER is to process the XML document using an event -driven parser, and map the XML element to the Java object according to the predetermined rules. Below is the workflow of the DIGESTER framework: 1. Create a Digestter object: First of all, we need to create a Digest object to analyze XML documents. Digester digester = new Digester(); 2. Configuration rules: Then, we need to configure a set of rules for the DIGESTER object. These rules specify the mapping relationship between XML elements and Java objects. digester.addObjectCreate("root/element", MyObject.class); digester.addSetProperties("root/element"); digester.addBeanPropertySetter("root/element/property", "propertyName"); The above code indicates that when the `ROOT> <Element>` element in the XML document is encountered, a MyObject object will be created and the attribute value and sub -element value of the XML element will be set to the attribute. 3. Analyze XML: Once the rules are configured, we can use the Digerster object to parse the XML document. MyObject myObject = (MyObject) digester.parse(inputStream); This statement will analyze the given XML input stream and return the Java object that matches the rule. In this way, we can easily convert complex XML documents into Java objects with layered structures. It should be noted that the DIGESTER framework can be used not only to resolve XML documents, but also to generate XML documents. In summary, the technical principle of the Apache Commons Digester framework is to analyze the XML document and map the XML element to the Java object according to the predetermined rules.This method simplifies the task of XML data processing, enabling developers to process and operate XML data more efficiently. I hope this article can help you understand the technical principles of the Apache Commons Digest framework.