The principle and practice of the "reconstruction 'framework technical principle in the Java library

The technical principles and practice of the "reconstruction 'framework' framework in the Java class library Abstract: Reconstruction is an important activity in software development, which aims to improve the readability, maintenance and scalability of code.The "reconstruction" framework technology in the Java class library provides developers with a way to automate reconstruction code.This article will introduce the work principle of the "reconstruction 'framework, and the practice of using the framework for code reconstruction. introduction: In the process of software development, with the change of demand and the evolution of the system, the structure and design of the code are often difficult to maintain clear and efficient.In this case, reconstruction is a very useful technology that can improve the quality of the code and reduce maintenance costs.However, manual reorganization is a time -consuming task, so the introduction of automated 'reconstruction' framework has become very important. The principle of reconstruction framework: The "reconstruction 'framework in the Java library is implemented based on a specific" reconstruction' mode and reflection mechanism.It analyzes and analyzes the code to find places that can apply the "reconstruction 'mode and automatically modify the code.Specifically, the 'reconstruction' framework includes the following main working steps: 1. Code analysis: 'Reconstruction' framework first analyzes the target code, and builds the code representation of the abstract syntax (AST) or other forms of code representation.This step can be completed using the API or other third -party tool libraries provided by the Java compiler. 2. Code analysis: Next, the "reconstruction 'framework will analyze the structure and semantics of the code, and find the place where the" reconstruction "mode can be applied.This involves the basic concepts of object -oriented programming, such as class, methods, fields, and inheritance relationships.This step usually requires the support of the parser and semantic analyzer. 3. Reconstruction mode matching: Once you find a place where you can apply the "reconstruction" mode, the "reconstruction 'framework will match the code fragment that meets the mode according to the predetermined reconstruction rules.These rules describe the method of code conversion and constraints. 4. Code modification: Once you find the matching code fragment, the "reconstruction 'framework will apply the corresponding' reconstruction 'mode to modify the code.Before modifying the code, it may also require additional inspection and verification to ensure that the modified code is still correct and reliable. 5. Code generation and replacement: Finally, the "reconstruction 'framework will make the modified code into the target code file and replace the original code file.In this way, developers can see the "reconstruction" code in the code library. Reconstruction framework practice: The following is a simple practical example, showing how to use the "reconstruction" framework in the Java class library to perform common reconstruction operations. Suppose we have an old code library, one of which is called "Customer", which contains a very lengthy method "CalculaTotalorderPrice". We decided to reconstruct it to two smaller methods. First of all, we need to introduce the 'reconstruction' framework in the Java class library and set up the working environment. import org.reflections.Reflections; import java.util.Set; // Use the reflex mechanism to scan the class Reflections reflections = new Reflections("com.example"); Set<Class<?>> classes = reflections.getSubTypesOf(Object.class); Next, we can use the rules defined by the "reconstruction 'framework to modify the code. // Import the necessary 'reconstruction' framework class import org.refactoring.example.ExtractMethodRefactoring; import org.refactoring.example.RefactoringExecutor; // Create a reconstruction object ExtractMethodRefactoring refactoring = new ExtractMethodRefactoring(); // Execute the reconstruction operation refactoring.setTargetClass(Customer.class); refactoring.setTargetMethod("calculateTotalOrderPrice"); refactoring.setNewMethodNames("calculateSubtotal", "calculateTax"); RefactoringExecutor executor = new RefactoringExecutor(); executor.execute(refactoring); In the above code, we use a "reconstruction" object called "ExtractMethodReFactoring", which can split a large method into multiple small methods.By setting the target class and methods, and specifying a new method name, we can perform the reconstruction operation.Finally, use "RefactoringExecutor" to perform reconstruction operations. in conclusion: The 'reconstruction' framework technology in the Java class library provides a way to automate the code reconstruction.By analyzing and analyzing the code, matching and modifying code fragments that conform to the "reconstruction 'mode, we can improve the quality and maintenance of the code.Through a reasonable application of reconstruction framework, developers can more efficient code reconstruction and improve the efficiency and quality of software development.