Java中的基本输入和输出

Question

我使用的是NetBeans IDE 7.4，我对Java非常陌生，我试图让用户输入两个数字（它们都是双精度），然后将它们存储在另一个变量中。我去了DOZENS的教程网站，他们不好。我怎样才能获得基本的输入和输出？

Answer 1

原始例如：

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); 
    } 

} 

UPDATE：
对不起，错过了这一点，要采取双打。在这里你去：

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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推荐阅读：

• 官方Oracle Java Tutorials - 这是非常丰富和容易理解
• 课：Basic I/O（从上面的教程）

Answer 2

import java.util.*; 

public class Test 
{ 
static Scanner console = new Scanner (System.in) 
public static void main (String[] args) 
{ 
double input1, input2; // Declares the double value of input1 and input2 
input1 = console.nextDouble(); // User inputs value into input1 
input2 = console.nextDouble(); 

String value1 = "" + input1; // Storing value into a String 
String value2 = "" + input2; 
// If you want to store it in let's say string. 
// Or else i think/int value1 = Integer.parseInt(input1); 
// This changes the double value into an Int value 
// Something like that. 
} 
} 

不太清楚，如果这是你的问题，因为输出值也可能是与

System.out.println(input1); // This outputs the value of input1 on the screen.