Java 只能从数组中的索引0中删除对象

我遇到的问题如下：我创建了两个表示船舶停靠空间的数组。第一个数组（dock1[]）ship对象（shipName和size-通常是超级容器）可以保存在数组中。如果要从dock1[]中删除对象，请输入shipName以将其删除

但是我只能从数组中的第一个空间（索引0）中删除ship对象，而不能从任何其他空间（即索引1,2,3）中删除ship对象

你能帮忙吗？下面是我的dock类，undock（）if语句中的问题：

import java.util.*;

public class Main {

static Scanner scan = new Scanner(System.in);

private static Ship[] dock1 = new Ship[10];
private static Ship[] waitingList = new Ship[10];

public static void main(String[] args) {
    menu();
}

public static void menu() {


    Scanner scan = new Scanner(System.in);


    while (true) {

        System.out.println("Choose an option: 1-3");
        System.out.println("1. Dock");
        System.out.println("2. Undock");
        System.out.println("3. Status");

        int menu = scan.nextInt();
        switch (menu) {
            case 1:
                System.out.println("1. Dock");
                dock();
                break;
            case 2:
                System.out.println("2. Undock");
                undock();
                break;
            case 3:
                System.out.println("3. Status");
                printDock();
                printWaitingList();
                break;
            case 4:
                System.out.println("4. Exit");
                System.exit(0);
            default:
                System.out.println("No such option");
                break;
        }
    }
}


public static void dock() {

    System.out.println("Enter ship's name: ");
    String name = scan.nextLine();

    System.out.println("Enter ship's size: ");
    String size = scan.nextLine();

    System.out.println("Enter the ships dock:");
    //Check if the dock number is valid
    int i = Integer.valueOf(scan.nextLine());
    if (i >= 0 && i < 10 && dock1[i] == null) {
        int c = 0;
        int co = 0;
        int sco = 0;
        for (int j = 0; j < dock1.length; j++) {
            if (dock1[j] != null && dock1[j].getShipSize().equals("Cargo")) {
                c++;
            }
            if (dock1[j] != null && dock1[j].getShipSize().equals("Container")) {
                co++;
            }
            if (dock1[j] != null && dock1[j].getShipSize().equals("Super-Container")) {
                sco++;
            }
        }

        if (c < 10 && co < 5 && sco < 2) {
            //Add ship to the dock
            dock1[i] = new Ship(name, size);
            System.out.println("Enough space you can dock");
            System.out.println("Ship has been docked");
        } else {
            System.out.println("You cannot dock");
            waitingList(name, size);
        }

    } else {
        System.out.println("Couldn't dock");
        waitingList(name, size);
    }

}


public static void undock() {
    System.out.println("Status of ships: ");
    printDock();
    System.out.println("Enter ship's name to undock: ");
    String name = scan.nextLine();

    for (int i = 0; i < dock1.length; i++) {
        if (dock1[i] != null && dock1[i].getShipName().equals(name)) { //ONLY FINDING in ARRAY 0
            dock1[i] = null;
            System.out.println("Ship removed");
            /// HERE CHECK IF SHIP IN DOCK
            for (int j = 0; j < waitingList.length; j++) {
                if (dock1[i] == null && waitingList[j] != null) {
                    // Add ship to the dock
                    dock1[i] = new Ship(waitingList[j].getShipName(), waitingList[j].getShipSize());
                    System.out.println("Move ship from waiting list to dock 1");
                    waitingList[j] = null;
                    return;
                } else {
                 //   System.out.println("No space in dock");
                    return;
                }
            }
        } else {
            System.out.println("Ship not docked here");
            break;
        }

    }

}

public static void waitingList(String name, String size) {

    System.out.println("Dock 1 is full, ship will try to be added to Waiting List");
    for (int i = 0; i < waitingList.length; i++) {
        if (waitingList[i] == null) {
            //Add ship to the dock
            waitingList[i] = new Ship(name, size);
            System.out.println("Enough space added to waiting list");
            return;
        } else {

        }
    }
    System.out.println("No space on waiting list, ship turned away.");
}

public static void printDock() {

    System.out.println("Docks:");

    for (int i = 0; i < dock1.length; i++) {
        if (dock1[i] == null) {
            System.out.println("Dock " + i + " is empty");
        } else {
            System.out.println("Dock " + i + ": " + dock1[i].getShipName() + " " + dock1[i].getShipSize());
        }
    }
}

private static void printWaitingList() {

    System.out.println("Waiting List:");

    for (int i = 0; i < waitingList.length; i++) {
        if (waitingList[i] == null) {
            System.out.println("Dock " + i + " is empty");
        } else {
            System.out.println("Dock " + i + ": " + waitingList[i].getShipName() + " " + waitingList[i].getShipSize());
        }
    }
}
}

import java.util.*；
公共班机{
静态扫描仪扫描=新扫描仪（System.in）；
私人静态船舶[]dock1=新船[10]；
私人静态船舶[]等待列表=新船舶[10]；
公共静态void main（字符串[]args）{
菜单（）；
}
公共静态无效菜单（）{
扫描仪扫描=新扫描仪（System.in）；
while（true）{
System.out.println（“选择一个选项：1-3”）；
System.out.println（“1.Dock”）；
System.out.println（“2.disock”）；
系统输出打印项次（“3.状态”）；
int menu=scan.nextInt（）；
开关（菜单）{
案例1：
System.out.println（“1.Dock”）；
dock（）；
打破
案例2：
System.out.println（“2.disock”）；
解开（）；
打破
案例3：
系统输出打印项次（“3.状态”）；
printDock（）；
printWaitingList（）；
打破
案例4：
System.out.println（“4.Exit”）；
系统出口（0）；
违约：
System.out.println（“无此选项”）；
打破
}
}
}
公共静态void dock（）{
System.out.println（“输入船名：”）；
字符串名称=scan.nextLine（）；
System.out.println（“输入船舶尺寸：”）；
字符串大小=scan.nextLine（）；
System.out.println（“进入船舶码头：”）；
//检查船坞号是否有效
int i=Integer.valueOf（scan.nextLine（））；
如果（i>=0&&i<10&&dock1[i]==null）{
int c=0；
int co=0；
int sco=0；
对于（int j=0；j

我看到两个错误：

1） 您可以在

undock

方法中中断else语句中的循环。 2） 如果您在第一个dock中找到船名，那么您总是在waitingList循环的第一次迭代中返回

for (int i = 0; i < dock1.length; i++) {
    if (dock1[i] != null && dock1[i].getShipName().equals(name)) { //ONLY FINDING in ARRAY 0
        dock1[i] = null;
        System.out.println("Ship removed");
        /// HERE CHECK IF SHIP IN DOCK
        for (int j = 0; j < waitingList.length; j++) {
            if (dock1[i] == null && waitingList[j] != null) {
                // Add ship to the dock
                dock1[i] = new Ship(waitingList[j].getShipName(), waitingList[j].getShipSize());
                System.out.println("Move ship from waiting list to dock 1");
                waitingList[j] = null;
                return;
            } else {
             //   System.out.println("No space in dock");
                return;
            }
        }
        // NOTE -> THIS ALWAYS ENDS IN A RETURN
    } else {
        System.out.println("Ship not docked here");
        break;
    }
}

我看到两个错误：

1） 您可以在

undock

方法中中断else语句中的循环。 2） 如果您在第一个dock中找到船名，那么您总是在waitingList循环的第一次迭代中返回

for (int i = 0; i < dock1.length; i++) {
    if (dock1[i] != null && dock1[i].getShipName().equals(name)) { //ONLY FINDING in ARRAY 0
        dock1[i] = null;
        System.out.println("Ship removed");
        /// HERE CHECK IF SHIP IN DOCK
        for (int j = 0; j < waitingList.length; j++) {
            if (dock1[i] == null && waitingList[j] != null) {
                // Add ship to the dock
                dock1[i] = new Ship(waitingList[j].getShipName(), waitingList[j].getShipSize());
                System.out.println("Move ship from waiting list to dock 1");
                waitingList[j] = null;
                return;
            } else {
             //   System.out.println("No space in dock");
                return;
            }
        }
        // NOTE -> THIS ALWAYS ENDS IN A RETURN
    } else {
        System.out.println("Ship not docked here");
        break;
    }
}

---

问题是，当一艘船没有停靠在第一个位置（索引0）时，你不会检查另一个p

 System.out.println("Status of ships: ");
printDock();
System.out.println("Enter ship's name to undock: ");
String name = scan.nextLine();
boolean deleted = false;
for (int i = 0; i < dock1.length; i++) {
    if (dock1[i] != null && dock1[i].getShipName().equals(name)) { //ONLY FINDING in ARRAY 0
        dock1[i] = null;
        System.out.println("Ship removed");
        deleted = true;
        /// HERE CHECK IF SHIP IN DOCK
        for (int j = 0; j < waitingList.length; j++) {
            if (dock1[i] == null && waitingList[j] != null) {
                // Add ship to the dock
                dock1[i] = new Ship(waitingList[j].getShipName(), waitingList[j].getShipSize());
                System.out.println("Move ship from waiting list to dock 1");
                waitingList[j] = null;
                return;
            } else {
                //   System.out.println("No space in dock");
                return;
            }
        }
    }

}
if (!deleted) System.out.println("No ship was removed")