Java 是什么原因引起的；“表达式开头非法”；错误？

我的方法中的大括号之前的表达式和分号通常是非法的。我真的需要一些帮助，因为我一辈子都不明白为什么我会犯这么多错误

public class stockItem{

    //Declaring Variables
    private double price;
    private  boolean delivery;
    private static int counter = 0;
    // New array with all the catagories stored in it
    private String[] catagoryArray = new String[] {"furniture", "silver", "mirrors", "jewelry", "miscellaneous"};
    private String Catagory;
    private String code;

    //default constructor for stockItem
    public stockItem(){
        price = 0;
        Catagory = catagoryArray[0];
        delivery = false;
        counter++;
        code = "default";
    }

    // Constructor for stockItem made by the user with all nessacey inputs
        public stockItem(String Catagory, double price, boolean delivery){
            for (int i =0; i < catagoryArray.length; i++){
                if (Catagory.equalsIgnoreCase(catagoryArray[i])){
                    this.Catagory = catagoryArray[i];
            } else {
                System.out.println("This is not a valid catagory!");
            }
            // Variables overwrite old variables from default stockItem
            this.price = price;
            this.delivery = delivery;
            counter++;
            code = code();
        }

        // Generates codes for each catagory and each item created
        private String getCode(){
            String furnCode = catagoryArray[0].substring(0,4) + counter;
            String silverCode = catagoryArray[1].substring(0,4) + counter;
            String mirrorsCode = catagoryArray[2].substring(0,4) + counter;
            String jewelry = catagoryArray[3].substring(0,4) + counter;
            String miscCode = catagoryArray[4].substring(0,4) + counter;
        }

        //Methods

        //Returns price of an object
        public double getPrice(){
            return price;
        }

        //Returns true of false for delivery of an object
        public boolean getDelivery(){
                return delivery;
        }

        //Returns the counter value
        public int getCounter(){
                return counter;
        }

        // Returns the catagory of an object
        public String getCatagory(){
                return Catagory;
        }

        // gets code of particular item
        public String getCode(){
                return code;
        }

        // Returns the amount of objects created
        public int objectAmount(){
            return counter;
        }

        //changes price of an object when called
        public void changePrice(double Price){
                this.price = Price;
        }

        // changes delivery option
        public void changeDelivery(boolean changeDelivery){
            this.delivery = changeDelivery;
        }

        // Changes catagory of an object
        public void changeCatagory(String changeCatagory){
            this.Catagory = changeCatagory;
        }

        //Prints a string containing all information about an object
        public String changeToString(){
            String Print = "Catagory:" + Catagory + "Price:" + price + "Amount Created" + counter + "Code" + code;
            return Print;
            }
        }
    }

公共类库存项目{
//声明变量
私人双价；
私人布尔传递；
专用静态整数计数器=0；
//新阵列中存储了所有类别
私有字符串[]分类数组=新字符串[]{“家具”、“银”、“镜子”、“珠宝”、“杂项”}；
私有字符串分类；
私有字符串码；
//stockItem的默认构造函数
公共物品（）{
价格=0；
分类法=分类法[0]；
交付=错误；
计数器++；
code=“默认”；
}
//由用户使用所有nessacey输入创建的stockItem的构造函数
公共库存项目（字符串分类、双倍价格、布尔交付）{
for（int i=0；i

这看起来不对：

code = code(); // where is code() defined?

您的

getCode（）

方法看起来也不正确，因为它有一个返回值，但不返回任何内容

最后：

//Prints a string containing all information about an object
public String changeToString(){
    String Print = "Catagory:" + Catagory + "Price:" + price + "Amount Created" + counter + "Code" + code;
    return Print;
    } // this should be removed
}

---

除了Eran指出的东西外，stockItems中还有一个无与伦比的大括号。for循环缺少最后一个大括号

public stockItem(String Catagory, double price, boolean delivery){
    for (int i =0; i < catagoryArray.length; i++){
        if (Catagory.equalsIgnoreCase(catagoryArray[i])){
            this.Catagory = catagoryArray[i];
        } else {
            System.out.println("This is not a valid catagory!");
        }

    } // This one.

    // Variables overwrite old variables from default stockItem
    // ... code ...
}

publicstockItem（字符串分类、双倍价格、布尔交付）{
for（int i=0；i

以下是有效代码。有几件事需要指出：

您应该命名一个类StockItem，而不是StockItem。阅读Java命名约定

您有tvo getCode（）方法。不能那样做。我将其中一个重命名为getCode1（）。选择一个你喜欢的名字。这个方法应该返回一个字符串

构造函数中缺少结束括号。我加了一些，但不确定位置是否正确

正如某人提到的，你应该考虑使用一些IDE。

public class StockItem {

    //Declaring Variables
    private double price;
    private boolean delivery;
    private static int counter = 0;
    // New array with all the catagories stored in it
    private String[] catagoryArray = new String[] {"furniture", "silver", "mirrors", "jewelry", "miscellaneous"};
    private String Catagory;
    private String code;

    //default constructor for StockItem
    public StockItem() {
        price = 0;
        Catagory = catagoryArray[0];
        delivery = false;
        counter++;
        code = "default";
    }

    // Constructor for StockItem made by the user with all nessacey inputs
    public StockItem(String Catagory, double price, boolean delivery) {
        for (int i = 0; i < catagoryArray.length; i++) {
            if (Catagory.equalsIgnoreCase(catagoryArray[i])) {
                this.Catagory = catagoryArray[i];
            } else {
                System.out.println("This is not a valid catagory!");
            }
        } // not sure if the closing bracket should be here
        // Variables overwrite old variables from default StockItem
        this.price = price;
        this.delivery = delivery;
        counter++;
        code = getCode();
    }

    // Generates codes for each catagory and each item created
    private String getCode1() {
        String furnCode = catagoryArray[0].substring(0, 4) + counter;
        String silverCode = catagoryArray[1].substring(0, 4) + counter;
        String mirrorsCode = catagoryArray[2].substring(0, 4) + counter;
        String jewelry = catagoryArray[3].substring(0, 4) + counter;
        String miscCode = catagoryArray[4].substring(0, 4) + counter;
        return ""; // this method should return a string!
    }

    //Methods

    //Returns price of an object
    public double getPrice() {
        return price;
    }

    //Returns true of false for delivery of an object
    public boolean getDelivery() {
        return delivery;
    }

    //Returns the counter value
    public int getCounter() {
        return counter;
    }

    // Returns the catagory of an object
    public String getCatagory() {
        return Catagory;
    }

    // gets code of particular item
    public String getCode() {
        return code;
    }

    // Returns the amount of objects created
    public int objectAmount() {
        return counter;
    }

    //changes price of an object when called
    public void changePrice(double Price) {
        this.price = Price;
    }

    // changes delivery option
    public void changeDelivery(boolean changeDelivery) {
        this.delivery = changeDelivery;
    }

    // Changes catagory of an object
    public void changeCatagory(String changeCatagory) {
        this.Catagory = changeCatagory;
    }

    //Prints a string containing all information about an object
    public String changeToString() {
        String Print = "Catagory:" + Catagory + "Price:" + price + "Amount Created" + counter + "Code" + code;
        return Print;
    }

}

公共类库存项目{
//声明变量
私人双价；
私人布尔传递；
专用静态整数计数器=0；
//新阵列中存储了所有类别
私有字符串[]分类数组=新字符串[]{“家具”、“银”、“镜子”、“珠宝”、“杂项”}；
私有字符串分类；
私有字符串码；
//StockItem的默认构造函数
公共物品（）{
价格=0；
分类法=分类法[0]；
交付=错误；
计数器++；
code=“默认”；
}
//由用户使用所有nessacey输入创建的StockItem的构造函数
公共库存项目（字符串分类、双倍价格、布尔交付）{
for（int i=0；i