java - Java 中的基本输入和输出

Question

我使用的是 NetBeans IDE 7.4，我是 Java 的新手，我试图让用户输入两个数字(都是双数)，然后将它们存储在另一个变量中。我去过 DOZENS 个教程站点，但它们都不好。我怎样才能得到基本的输入和输出？

Answer 1

原始示例:

import java.util.Scanner;

public class TestIO {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.println("Print something:");    // printing output
        String text = scanner.nextLine();          // taking input

        System.out.println("You have printed the following text: " + text);
    }

}

更新:
对不起，错过了要点，你想参加 double 。给你:

import java.util.Scanner;
import java.util.InputMismatchException;

public class TestIO {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        double firstDouble = 0L;
        double secondDouble = 0L;
        while (true) {  // take input (two doubles) until successful
            System.out.println("Print two doubles (press enter after each input):");
            try {
                firstDouble = scanner.nextDouble();
                secondDouble = scanner.nextDouble();
            } catch (InputMismatchException e) {
                System.out.println("Wrong input. You must print doubles.\n" +
                                   "Depending on your locale, as a decimal separator " +
                                   "use either a comma or a dot.\n");
                scanner.nextLine(); // clearing the buffer with the wrong input
                                    // to avoid infinite loop
                continue;
            }
            break; 
        }
        // Printing the user input (limiting doubles to 3 decimal places)
        System.out.format("You have printed %.3f and %.3f %n", 
                          firstDouble, secondDouble);
    }
}

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