java-tutorials/gradle-5/cmd-line-args/build.gradle

apply plugin: "java"
apply plugin: "application"
description = "Gradle Command Line Arguments examples"

ext.javaMainClass = "com.baeldung.cmd.MainClass"

application {
    mainClassName = javaMainClass
}

task propertyTypes(){
    doLast{
        if (project.hasProperty("args")) {
            println "Our input argument with project property ["+project.getProperty("args")+"]"
        }
        println "Our input argument with system property ["+System.getProperty("args")+"]"
    }
}

if (project.hasProperty("args")) {
    ext.cmdargs = project.getProperty("args")
} else { 
    ext.cmdargs = "ls"
}

task cmdLineJavaExec(type: JavaExec) {
    group = "Execution"
    description = "Run the main class with JavaExecTask"
    classpath = sourceSets.main.runtimeClasspath
    main = javaMainClass
    args cmdargs.split()
}

task cmdLineExec(type: Exec) {
    group = "Execution"
    description = "Run an external program with ExecTask"
    commandLine cmdargs.split()
}