java - 如何从数组中初始化一个数字

Question

我需要从数组中获取一个数字并将其初始化为变量，以便我可以将其用作对象。我不确定是否只是这样，

intsmallSpaces = 1; 例如。

有人知道我该怎么做吗？

public class Port {
    public static void main(String[] args) throws IOException {
        Scanner console = new Scanner(System.in);

        String shipSize = null;
        String shipName = null;

        int smallSpaces = 1;
        int mediumSpaces = 2;
        int largeSpaces = 3;

        int[][] dockSpaces = {
            {1, 1, 1, 1, 1, 2, 2, 2, 3, 3},
            {1, 1, 1, 1, 1, 2, 2, 2, 3, 3},
            {1, 1, 1, 1, 1, 2, 2, 2, 3, 3},
        };

        int waitingList = 10;
        int menuChoice = 0;

        while (true) {
            System.out.println("SHIP PORT APPLICATION");
            System.out.println("\n1. Add ship to port.");
            System.out.println("\n2. Remove ship from port.");
            System.out.println("\n3. View report.");
            System.out.println("\n4. Exit.");

            menuChoice = console.nextInt();

            switch (menuChoice) { // Using a switch case for the menu options
                case 1:
                    System.out.println("Add ship to port");
                    break;
                case 2:
                    System.out.println("Remove ship from port");
                    break;
                case 3:
                    System.out.println("View report");
                    break;
                case 4:
                    System.out.println("Exit");
                    break;
                default:
                    System.out.println("Invalid Choice");
            }

            try {
                FileWriter write = new FileWriter("PortLog.txt", true);
                BufferedWriter out = new BufferedWriter(write);

                if (menuChoice == 1) {
                    System.out.println("Please select ship size(1. Cargo /n 2.Container /n 3. SuperContainer)");
                    shipSize = console.next();

                    System.out.println("Please enter the name of your ship");
                    shipName = console.next();

                    if (shipSize.equals("1")) {
                        smallSpaces++;
                        System.out.println("test");
                        write.write("SMALL"); // Printing line to output file about the transaction details
                        out.newLine();  //Adding new line to file writer
                        out.close();
                    }
                }
            } catch (Exception e) {
                System.out.println("Error: " + e.getMessage());
            }
        }
    }
}

Answer 1

初始化一个int

int a = 1;

就够了。但是，虽然这是一个变量，但它不是一个对象，而是一个原始类型。对象需要使用关键字new来创建，而基本类型则不需要，在java中基本类型有byte、short、int、long、float、double、boolean、char。从初始化的角度来看，字符串是一种特殊情况，因为它可以用字符串文字进行初始化。

原语:

int a = 1;
char c = 'c';
boolean b = true;
...

对象:

Object a = new Object();
ClassA class = new ClassA();
...