如何創(chuàng)建一個使用另一個類的變量或調用整個構造函數(shù)的 java 對象？比如accountNumber, firstName, lastName, phone都是傳入address的變量，由street, city, state, zip組成，已經創(chuàng)建好了：Address address = new Address(street, city, state, zip);數(shù)據僅由兆字節(jié)組成，并且已經創(chuàng)建：Data data = new Data(megabytes);這就是我對客戶對象的看法：Customer customer = new Customer(accountNumber, firstName, lastName, address, phone, data);這應該是一個“重載的構造函數(shù)”，但我不明白那是什么意思。這是我到目前為止的構造函數(shù)：public Customer(String accountNumber, String firstName, String lastName, Address address, int phone, Data megabytes){ this.accountNumber = accountNumber; this.firstName = firstName; this.lastName = lastName; this.address = address; this.phone = phone; this.megabytes= megabytes; }我收到錯誤：The constructor Customer(String, String, String, Address, int, Data) is undefined
1 回答
12345678_0001
TA貢獻1802條經驗 獲得超5個贊
乍一看，一切似乎都很好。我希望你在編譯之前保存了文件。
既然你提到你不明白什么是重載構造函數(shù)，我會盡力解釋一下。
重載的構造函數(shù)具有相同的構造函數(shù)名稱，但它在以下方面與其他構造函數(shù)不同 -
它有不同數(shù)量的正式參數(shù)
構造函數(shù)形參類型順序不同
這是一個例子 -
public class Customer {
private String firstName;
private String lastName;
private int phoneNumber;
public Customer() {
// default constructor
}
public Customer(String firstName) {
this.firstName = firstName;
}
public Customer(String firstName, String lastName) {
this.firstName = firstName;
this.lastName = lastName;
}
public Customer(String firstName, String lastName, int phoneNumber) {
this.firstName = firstName;
this.lastName = lastName;
this.phoneNumber = phoneNumber;
}
public Customer(int phoneNumber, String firstName, String lastName) {
this.phoneNumber = phoneNumber;
this.firstName = firstName;
this.lastName = lastName;
}
// This is not an overloaded constructor as there is already a constructor of type
// Customer(String, String)
// public Customer(String lastName, String firstName) {
// this.lastName = lastName;
// this.firstName = firstName;
// }
}
添加回答
舉報
0/150
提交
取消