JAVA：如何組合消息框與多個輸出

Question

我正在學習Java，並有一個相當簡單的程序，返回一系列符合Collatz Conjecture的數字。我可以將它輸出到控制檯或彈出多個JOptionPane.showMessageDialog()窗口，每個窗口都有一個。

我該如何結合JOptionPane.showMessageDialog()的顯示所有的輸出在一個JOptionPane.showMessageDialog()？

代碼：

package collatz; 

import java.util.Random; 
import javax.swing.*; 

public class Collatz { 

/** 
* Demonstrates the Collatz Cojecture 
* with a randomly generated number 
*/ 

public static void main(String[] args) { 
    Random randomGenerator = new Random(); 
    int n = randomGenerator.nextInt(1000); 

    JOptionPane.showMessageDialog(null, "The randomly generated number was: " + n); 


    while(n > 1){ 
     if(n % 2 == 0){ 
      n = n/2; 
      JOptionPane.showMessageDialog(null, n); 
     } 
     else{ 
      n = 3 * n + 1; 
      JOptionPane.showMessageDialog(null, n); 
     } 
    } 

    JOptionPane.showMessageDialog(null, n); 
    JOptionPane.showMessageDialog(null, "Done."); 

} 

} 

謝謝！

- ZuluDeltaNiner

Answer 1

跟蹤滿弦的要被顯示，則在結束顯示它：

public static void main(String[] args) { 
    Random randomGenerator = new Random(); 
    int n = randomGenerator.nextInt(1000); 

    StringBuilder output = new StringBUilder("The randomly generated number was: " + n + "\n"); 

    while(n > 1){ 
     if(n % 2 == 0){ 
      n = n/2; 
     } 
     else{ 
      n = 3 * n + 1; 
     } 
     output.append(n + "\n"); 
    } 

    output.append("Done."); 
    JOptionPane.showMessageDialog(null, output); 

}