命令行参数
命令行参数是在执行程序时紧跟在程序名字后面的信息
public class CommandLine {public static void main(String[] args){ for(int i=0; i<args.length; i++){System.out.println("args[" + i + "]: " + args[i]);}}
}
$ javac CommandLine.java
$ java CommandLine this is a command line 200 -100
args[0]: this
args[1]: is
args[2]: a
args[3]: command
args[4]: line
args[5]: 200
args[6]: -100
可变参数
传递方法:typeName… parameterName
一个方法中只能指定一个可变参数,且必须在参数列表最后
public class VarargsDemo {public static void main(String[] args) {// 调用可变参数的方法printMax(34, 3, 3, 2, 56.5);printMax(new double[]{1, 2, 3});}public static void printMax( double... numbers) {if (numbers.length == 0) {System.out.println("No argument passed");return;}double result = numbers[0];for (int i = 1; i < numbers.length; i++){if (numbers[i] > result) {result = numbers[i];}}System.out.println("The max value is " + result);}
}