Objective
(1). Create a class and write the program source code in the editor;
Note:
The command line parameters are array args of String type in the main method. You can use the Integer.valueOf() method to convert the string into an integer type, for example:
int number= Integer.valueOf(“12321421”)
The parameters of this method can only be numeric strings
(2), compile the program;
(3), run the program.
Online video learning tutorial sharing: java free video tutorial
Experimental part
Experimental code:
public class Average { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub //獲取三個(gè)字符參數(shù) String one = args[0]; String two = args[1]; String three = args[2]; //將三個(gè)字符參數(shù)轉(zhuǎn)為浮點(diǎn)型 double int_One = Double.valueOf(one).doubleValue(); double int_Two = Double.valueOf(two).doubleValue(); double int_Three = Double.valueOf(three).doubleValue(); double average = (int_One + int_Two + int_Three) / 3; System.out.println("平均數(shù)為:"+average); } }
Program in MyEclipse, try the cmd command to compile and run.
Command line to compile java files:
javac Average.java
PS: javac is the command to compile java files, Average.java is your java file
command Run the java file:
java Average 3 4 5
PS: java is the command to run the java file, Average is the Java file name, and 3, 4, and 5 are the parameters to be passed to the main function.
Run results:
Recommended related articles and tutorials: Getting started with java development
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