Best Practices for Util Args Framework in Java Class Libraries

The best practice of the Util ARGS framework in the Java class library introduce Util ARGS is a parameter parsing library commonly used in the Java library. It can easily process command line parameters and configuration file parameters.In the development of the Java class library, reasonable use of the Util ARGS framework can provide better code readability and maintenance.This article will share some of the best practices that use the Util ARGS framework in the Java library, as well as related programming code and configuration description. 1. Why use Util ARGS framework When developing the Java library, parameters are often required from the command line or configuration file.The Util ARGS framework provides a simple and powerful way to handle these parameters.It can help us define the parameter form we need, automatically generate parameter help information, verify the legality of the parameters, and provide friendly wrong prompts.Therefore, using the Util ARGS framework can greatly simplify the process of parameter analysis and improve the reliability of the code. 2. The way to introduce Util ARGS framework To use the Util ARGS framework in the Java class library, you need to add the following dependencies in the constructing configuration file (such as Maven's pom.xml): <dependency> <groupId>com.beust</groupId> <artifactId>jcommander</artifactId> <version>1.72</version> </dependency> In this way, you can introduce the Util ARGS framework and start using it. Third, the best practice using Util ARGS framework 1. Define parameter class When using the Util ARGS framework, we need to define a parameter class first, and each field corresponds to different parameters.For example: import com.beust.jcommander.Parameter; public class AppArgs { @Parameter(names = {"--input", "-i"}, description = "Input file name", required = true) public String input; @Parameter(names = {"--output", "-o"}, description = "Output file name") public String output; // ... other parameters ... } In the above examples, we define two parameters `input` and` Output`, which represent the input file name and output file name, respectively. 2. Analysis parameters Before using the Util ARGS framework to parse the parameters, we need to create a parameter parser object and specify the parameter class to be parsed.Then, just call the `PARSE ()" method of the parser object, and the parameters in the command line parameter or configuration file can be parsed to the corresponding parameter instance.For example: import com.beust.jcommander.JCommander; public class App { public static void main(String[] args) { AppArgs appArgs = new AppArgs(); JCommander commander = JCommander.newBuilder().addObject(appArgs).build(); commander.parse(args); // Use the parsing parameters for follow -up operation // ... } } In the above example, we created a parameter instance `appargs`, and then created a parameter parser` Commander`, and specified the parameter class to be parsed.Finally, call the `PARSE ()` method to analyze the command line parameters or the parameters in the configuration file to the `appargs`. 3. Error processing and help information The Util ARGS framework provides rich error processing and help information.When the parameter parses errors, it automatically provides corresponding error prompts.And when the user passs into the parameter of `-help` or` -H`, the framework will automatically generate help information and output.For example: public class App { public static void main(String[] args) { AppArgs appArgs = new AppArgs(); JCommander commander = JCommander.newBuilder().addObject(appArgs).build(); try { commander.parse(args); } catch (Exception e) { System.err.println(e.getMessage()); Commander.usage (); // Output help information System.exit(1); } // Use the parsing parameters for follow -up operation // ... } } In the above example, we added an anomalous processing, capturing and output error messages during the analysis parameters.If an error occurs, we will output error information to the standard error flow, and call the `usage ()` method output help information.Finally, withdraw the program by calling the `System.exit (1)`. Fourth, summary By using the Util ARGS framework reasonably, we can easily handle command line parameters and configuration file parameters in the development of the Java class library to improve the readability and maintenance of the code.This article introduces the best practice of the Util ARGS framework, including the way to introduce frameworks, define parameters, parsing parameters, and output of incorrect processing and help information. I hope this article will help you use the Util ARGS framework in the development of the Java library!