以下是演示使用“聚合”或在 Java 中具有 -a 关系的 Java 代码。
class Address{
private String addressLine;
public String getAddressLine(){
return addressLine;
}
public void setAddressLine(String address){
addressLine=address;
}
}
class Customer{
private int customerId;
private Address address;
private static int counter = 1000;
public Customer{
customerId=++counter;
}
public int getCustomerId(){
return customerId;
}
public void set Address(Address address){
this.address=address;
}
public Address getAddress(){
return address;
}
}
class Retail{
public static void main(String args[]){
Address add=new Address();
add.setAddressLine("Washington Street");
Customer custObj = new Customer();
custObj.setAddress(add);
Address temp = custObj.getAddress();
System.out.println("Address");
System.out.println(temp.getAdressLine());
}
}
无法理解此处代码的某些部分。请解释程序执行。另外,为什么我们必须将 get address 的值存储在 temp 中才能打印出来?还有其他方法吗?