"JannoCessor Framework Introduction Guide: Quickly Improve the Development Efficiency of Java Library Library"

JannoCessor Framework Introduction: Quickly Improve the development efficiency Overview: JannoCessor is an open source framework for accelerating the development of the Java library.Through the annotation of automation processing code, it realizes the function of automatically generating repeated code, thereby improving the efficiency of developers.This article will introduce the basic concepts and usage of JannoCessor, and provide some Java code examples to help readers better understand and apply the framework. 1 Introduction During the development of the Java library, we often encounter repeated and mechanical work, such as defining attributes, generating the Getter and Setter method.These repetitive code not only spend time, but also easily introduce errors, reducing development efficiency.The emergence of the JannoCessor framework is to solve this problem. It automatically generates these repetitive codes by annotating the processor, which greatly simplifies the development process. 2. The basic concept of the JannoCessor framework 2.1 Note processor The annotation processor is one of the core components of the JannoCessor framework.It analyzes the annotations in the Java source code to generate a new Java code or modify the existing Java code.By customizing the annotation processor, we can achieve different code generation logic, thereby meeting various development needs. 2.2 Note Note is a special label to provide programmer data to the compiler and other tools.In the JannoCessor framework, we can define our own annotations and use the annotation processor to automatically generate the corresponding code. 3. JannoCessor usage 3.1 Add JannoCessor dependencies First, we need to add JannoCessor dependencies to the construction file of the project.Assuming that we use Maven to build a project, we can add the following dependencies to pom.xml: <dependency> <groupId>org.jannocessor</groupId> <artifactId>jannocessor</artifactId> <version>1.0.0</version> </dependency> After adding dependencies, execute the Maven construction command to introduce JannoCessor into the project. 3.2 Definition annotation Next, we need to define an annotation to generate code.For example, we can define an annotation. import java.lang.annotation.*; @Retention(RetentionPolicy.RUNTIME) @Target(ElementType.TYPE) public @interface GenerateGetterSetter { } In this example, the retention strategy of the annotation specifies the retention strategy of the annotation is Runtime, that is, you can still read the annotation information through the reflection mechanism at runtime.`@Target` Specify the target of the annotation, the target of the annotation is Type, that is, the annotation of the class level. 3.3 Writing an annotation processor Next, we need to write an annotation processor to generate the corresponding code based on the `@geenerategettersetter`. import org.jannocessor.model.modifier.VisibilityModifier; import org.jannocessor.processor.GenericBeanProcessor; public class GetterSetterProcessor extends GenericBeanProcessor<GenerateGetterSetter> { @Override protected void processElement(JavaClassSource entity, GenerateGetterSetter annotation) { entity.addGetter().setVisibility(VisibilityModifier.PUBLIC); entity.addSetter().setVisibility(VisibilityModifier.PUBLIC); } } In this example, we inherited the `GENERICBEANPROCESSOR` class and implemented the` Processelement` method.In this method, we can add new members to the Java class, such as Getter and Setter methods. 3.4 Use the annotation processor Finally, we need to apply the annotation processor in the project.In the Maven project, you can specify the use of the annotation processor by configure the `Maven-Compiler-Plugin`. <build> <plugins> <plugin> <artifactId>maven-compiler-plugin</artifactId> <version>3.8.1</version> <configuration> <annotationProcessors> <annotationProcessor>com.example.GetterSetterProcessor</annotationProcessor> </annotationProcessors> </configuration> </plugin> </plugins> </build> Through the above configuration, Maven will automatically call our defined annotation processor to generate the corresponding code when compiling.After the compilation is completed, we can see the generated Getter and Setter method in the generated class file. 4. Summary This article introduces the basic concepts and usage of the JannoCessor framework, and provides a simple example to show how to use the framework.Through the JannoCessor framework, we can greatly improve the efficiency of the development of the Java library and reduce the writing of duplicate code.It is hoped that readers can better understand and apply the JannoCessor framework through the introduction of this article, and achieve better results in actual development.