設(shè)計(jì)Kotlin命令行應(yīng)用的結(jié)構(gòu)時(shí),可以考慮以下幾個(gè)方面來確保代碼的可維護(hù)性和可擴(kuò)展性:
my-cli-app/
├── build.gradle.kts
├── settings.gradle.kts
├── src/
│ ├── main/
│ │ ├── kotlin/
│ │ │ ├── com/
│ │ │ │ ├── mycliapp/
│ │ │ │ │ ├── Main.kt
│ │ │ │ │ ├── CommandLineArgs.kt
│ │ │ │ │ ├── Commands.kt
│ │ │ │ │ └── ...
│ │ └── resources/
│ └── test/
│ ├── kotlin/
│ │ ├── com/
│ │ │ ├── mycliapp/
│ │ │ │ ├── MainTest.kt
│ │ │ │ └── ...
│ └── resources/
├── .gitignore
├── README.md
└── ...
Main.kt
和命令行參數(shù)解析CommandLineArgs.kt
。com.mycliapp.commands/
├── HelpCommand.kt
├── GreetCommand.kt
├── ...
com.mycliapp.services/
├── UserService.kt
├── DataService.kt
├── ...
com.mycliapp.models/
├── User.kt
├── Settings.kt
├── ...
在build.gradle.kts
中定義依賴項(xiàng):
plugins {
kotlin("jvm") version "1.5.31"
application
}
group = "com.mycliapp"
version = "1.0-SNAPSHOT"
repositories {
mavenCentral()
}
dependencies {
implementation(kotlin("stdlib"))
implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.5.2")
testImplementation("org.junit.jupiter:junit-jupiter-api:5.7.0")
testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.7.0")
}
application {
mainClass.set("com.mycliapp.MainKt")
}
使用JCommander
或args4j
等庫(kù)來解析命令行參數(shù):
import com.beust.jcommander.JCommander
import com.beust.jcommander.Parameter
data class CommandLineArgs(
@Parameter(names = ["-n", "--name"], description = "Your name")
val name: String? = null,
@Parameter(names = ["-v", "--version"], description = "Print version")
val version: Boolean = false
)
fun main() {
val args: CommandLineArgs = JCommander.newBuilder()
.addObject(args)
.build()
.parse()
if (args.version) {
println("My CLI App version 1.0")
return
}
when (args.name) {
null -> println("Please provide your name using -n or --name option")
else -> println("Hello, $args.name!")
}
}
每個(gè)命令可以是一個(gè)函數(shù)或一個(gè)類:
package com.mycliapp.commands
fun helpCommand(args: CommandLineArgs) {
println("Usage: mycliapp [command] [options]")
println("Available commands:")
println(" help Show this help message")
println(" greet <name> Greet the specified name")
}
在Main.kt
中調(diào)用命令解析器和命令執(zhí)行器:
package com.mycliapp
import com.beust.jcommander.JCommander
import com.mycliapp.commands.*
fun main() {
val args: CommandLineArgs = JCommander.newBuilder()
.addObject(args)
.build()
.parse()
val commander = JCommander.newBuilder()
.addObject(args)
.build()
when (args.name) {
null -> helpCommand(args)
else -> {
when (args.name.toLowerCase()) {
"greet" -> GreetCommand(args).execute()
else -> helpCommand(args)
}
}
}
}
編寫單元測(cè)試和集成測(cè)試來確保應(yīng)用的各個(gè)部分正常工作:
package com.mycliapp.commands
import org.junit.jupiter.api.Test
import static org.junit.jupiter.api.Assertions.*
class HelpCommandTest {
@Test
fun testHelpCommand() {
val args = CommandLineArgs()
args.name = null
val output = java.io.ByteArrayOutputStream()
System.setOut(java.io.PrintStream(output))
helpCommand(args)
val outputString = output.toString()
assertTrue(outputString.contains("Usage: mycliapp [command] [options]"))
assertTrue(outputString.contains("Available commands:"))
}
}
通過以上結(jié)構(gòu),你可以確保Kotlin命令行應(yīng)用具有良好的組織結(jié)構(gòu)和可維護(hù)性。