小编ysh*_*vit的帖子

public class Bird
{
    private static int id = 0;
    private String kind;

    public Bird(String requiredKind)
    {
        id = id + 1;
        kind = requiredKind;
    }

    public String toString()
    {
        return "Kind: " + kind + ", Id: " + id + "; ";
    }

    public static void main(String [] args)
    {
        Bird [] birds = new Bird[2];
        birds[0] = new Bird("falcon");
        birds[1] = new Bird("eagle");
        for (int i = 0; i < 2; i++)
            System.out.print(birds[i]);
        System.out.println();
    }
}

为什么这会回来 …

如何使用重复来命名Java中的对象？我想创建52个这样的对象(卡片)

Card1
Card2
...
Card52

我在想这样的事情

int i=1;

while (i<=52){
  Card Card<i> = new Card();
  i=i+1;
}

我怎样才能让它发挥作用？

不是三元运算符假设像arg一样工作？真假 ？？？所以如果持续时间和石油超过规定的数量而不是字段变量,它应该返回true ..但是这会返回false

public class test12 {
    int duration = 260;
    int petroleum = 300;
    boolean result;

    public void checktrain(){
        boolean result = duration>=250 && petroleum>=235? true : false;
        this.result = result;
    }

    public void run(){
        System.out.print(result);
    }

    public static void main(String args[]){
        test12 tr = new test12();
        tr.run();
    }
}

这是我得到的错误......

Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at Maze.Map.readFile(Map.java:60)
at Maze.Map.<init>(Map.java:23)
at Maze.Board.<init>(Board.java:16)
at Maze.Maze.<init>(Maze.java:15)
at Maze.Maze.main(Maze.java:9)

以下是我的代码!

package Maze;

import javax.swing.*;

public class Maze 
{

    public static void main(String[] args)

    {
        new Maze();
    }

    public Maze()

    {

        JFrame f = new JFrame();

        f.setTitle("Maze Game");

        f.add(new Board());
        f.setSize(464, 485);
        f.setLocationRelativeTo(null);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

package Maze;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Board extends JPanel implements ActionListener
{

    private Timer timer;

    private Map …

它达到了必须打印线的程度System.out.printf("%4s%22s%24s\n","Year"...),然后在没有打印的情况下停止.

public class WorldPopulationGrowth {

    /**
     * @param args
     */
    public static void main(String[] args) {
        Scanner input = new Scanner( System.in);
        long BasePopulation; //The base, or current population
        double GrowthRate; //The rate of increase
        double GrowthResult; // The pop after growth rate increase

        //Time to obtain the numbers needed for Calculation
        //Specifically, the growth rate and the base population
        System.out.println("Welcome to the world population calculator");
        System.out.print("Enter the current world population:");
        BasePopulation = input.nextLong();
        System.out.println("Enter the current growth …

我的java应用程序收到此错误.我相信故障是我的数组列表的添加功能.有没有更好的方法来融入这个想法而不会过于复杂？(java的第一周)非常感谢!

import java.util.ArrayList;
import java.util.Scanner;


public class PrimeSieve {
    public static void main(int[] args) {
        System.out.println("Enter the max integer(N value): ");
        Scanner scan = new Scanner(System.in);
        int num = scan.nextInt();
        System.out.println("Compute prime numbers from 2 to: " + num);
        if(num < 2){
            System.out.println("N must be greater than or equal to 2.");
        }
        else if(num == 2) {
            System.out.println("Prime numbers: 2");
        }
        else {
            ArrayList<Integer> myArr = new ArrayList<Integer>(); 
            int i = 2;
            while(i <= num){
                myArr.add(i);
            }
            System.out.println(myArr);
        }
    } …

我不确定如何在Java语言中输出以下内容.注意输出中存在双短划线:

String keyName = projectId.AsString + "-comments-" + creationMomentString + "-" + _rand.nextInt() +  ".txt";
System.out.println(creationMomentString);
System.out.println(_rand.getClass());
System.out.println(keyName);

输出:

0000001466400377645
class java.security.SecureRandom
o7grn3qt-comments-0000001466400377645--874329600.txt


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给定"The brown fox jumped the fence jumped. The jumped fox? The fox. Jumped"通过空格分割的句子在数组中显示空字符串.我期待带有标点符号的单词或单词.这句空字符从哪里来的？