The implementation principle and application instance of the Chicory CLI framework in the Java library
The Chicory CLI framework is a Java class library used to build a command line interface application. It provides a simple and powerful way to realize the command line interaction and process user input.This article will explore the implementation principles of the Chicory CLI framework in the Java class library, and explain the complete programming code and related configuration through an application instance.
## implementation principle
The Chicory CLI framework is based on the Java's reflection mechanism and annotation. It uses annotations to mark the command line commands and parameters, and realize the corresponding method of dynamic calling through the reflection mechanism.The principle of realization is mainly divided into the following steps:
1. Define the command line commands and parameters: Use the annotation provided by the Chicory Cli to mark the Java method and parameters, and convert it into an executable command line command.
2. Analyze the user input: The Chicory Cli framework will analyze the command line parameters of the user input and map it to the corresponding Java method and parameters.
3. Methods through reflection: According to the commands and parameters entered by the user, the corresponding method is dynamically called using the reflex mechanism of the Java.
4. Processing method Return results: The framework will convert the return result of the method into an appropriate output form and display it to the user.
## Applications
In order to better understand the application of the Chicory CLI framework, we will demonstrate its use method through a simple example.
Suppose we are developing an command line calculator application to support addition, subtraction and multiplication operations.We can use the Chicory CLI framework to implement the application. The following are some example code and configuration files:
import io.chicori.CLIApplication;
import io.chicori.annotations.Command;
import io.chicori.annotations.Option;
public class CalculatorApp {
@Command(name = "add", description = "Perform addition operation")
public int add(@Option(name = "a") int a, @Option(name = "b") int b) {
return a + b;
}
@Command(name = "subtract", description = "Perform subtraction operation")
public int subtract(@Option(name = "a") int a, @Option(name = "b") int b) {
return a - b;
}
@Command(name = "multiply", description = "Perform multiplication operation")
public int multiply(@Option(name = "a") int a, @Option(name = "b") int b) {
return a * b;
}
public static void main(String[] args) {
CLIApplication.run(CalculatorApp.class, args);
}
}
In the above example, we define a `CalculatorApp` class, which contains three methods, which are used to perform addition, subtraction and multiplication operations.These methods use annotations provided by the Chicory CLI framework to mark commands and parameters.Each command defines the name and description, and each parameter defines the name.
In the `Main` method, the Chicory CLI framework was started using the` Cliapplication.run () method, and the `Calculatorapp` class was passed as parameters to the method.
Through the above code and the following configuration files, we can build a complete command line calculator application:
yaml
name: CalculatorApp
description: A command-line calculator application
commands:
- name: add
description: Perform addition operation
arguments:
- name: a
description: First number
type: integer
- name: b
description: Second number
type: integer
- name: subtract
description: Perform subtraction operation
arguments:
- name: a
description: First number
type: integer
- name: b
description: Second number
type: integer
- name: multiply
description: Perform multiplication operation
arguments:
- name: a
description: First number
type: integer
- name: b
description: Second number
type: integer
The above is a simple YAML configuration file, which contains the name, description, and details of each command.In this configuration file, we define the three commands of the `add ',` subtract` and `multiply`, and specify the parameters of each command.
Through the above code and configuration files, we can compile and run this command line calculator application.Users can enter different commands and parameters through command lines. The application will perform corresponding operations and return the result to the user.
The above is the implementation principle of the Chicory CLI framework in the Java class library and a simple application example.By using the Chicory CLI framework, we can easily build a powerful command line application and provide flexible and friendly interaction methods.
