How to write a constructor in java
1. java constructor
Also called constructor, it is a special function in java. The function name is the same as the class name and has no return value.
Function: Generally used to initialize member properties and member methods, that is, after the new object is generated, the properties and methods of the object are called. (Recommended tutorial: java tutorial )
2. Characteristics of constructors
1. The function name is the same as the class name
2. There is no need to define the return value type. (Unlike the void type return value, void has no specific return value type; the constructor does not even have a type)
3. You cannot write a return statement. (There is no return value type, so there is no need for a return statement)
Note: General functions cannot call constructors, only constructors can call constructors.
3. Write a constructor
public class ConfunDemo {
public static void main(String[] args) {
// //輸出Hello World。new對象一建立，就會調(diào)用對應的構造函數(shù)Confun()，并執(zhí)行其中的println語句。
Confun c1=new Confun();
}
}
class Confun{
Confun(){
//定義構造函數(shù)，輸出Hello World
System.out.println("Hellow World");
}
}Through the above example, we can easily write a constructor of our own, go and try it!
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