Use of no parameter-return-value method in Java
1, defining the method
Eg:public void Show () {
System.out.println ("helloworld!")
}
---method to implement a specific action in a pair of curly braces
---naming specification, first word letter lowercase, other words first letter uppercase
---Call the method, create the object first, and then manipulate it by the object name. Method Name ().
Eg:public class helloworld{
public static void Main (string[] args) {
HelloWorld Hello = new HelloWorld ();//Create object, object named Hello
Hello.show ();//Call Object
}
public void Show () {//define Method
System.out.println ("helloworld!");
}
}
N!!! Use of the non-parametric return value method in Java
Defines a method that has no parameters but returns a value of type int
public int Add () {
int A=5;int b=4;
int sum=a+b;
return sum;
}//returns a value of type int in the Add method, so you must return an integer value using return in the method body
When a method with a return value is called---, the method returns a result when it is executed, so the return value is typically received and processed when a method with a return value is called
Here are a few things to note n!!
---If the return type of the method is void, it is not possible to return a value with return in the method.
The return value of a---method can have at most one
---method return value type must be compatible with eg return type int cannot return string type
N!!! Use of no return value method with parameters in Java
Eg:public void Show (String name) {
System.out.println ("Welcome" +name+ "!");
}
HelloWorld Hello = new HelloWorld ();
Hello.show ("NSU");
The output is Welcome nsu!
---Call the parameter method, you must ensure that the number, type, and order of the arguments are the same as the formal parameters!
---The method is called, the argument does not need to specify the data type Eg:hello.show ("Welcome");
---method can be a basic data type Eg:int double, etc. can also be a reference data type String array, etc.
When there are multiple---methods, multiple parameters are separated.
N!!! Use of the return value method with a parameter in Java
Eg:public string Show (string name) {//defines a method with a parameter return value
Return "Welcome" +NAME;
}
HelloWorld hello= new HelloWorld ();
String welcome=hello.show ("NSU");//Call the method with the return value of the parameter, save the return value in the variable welcome
SYSTEM.OUT.PRINTLN (welcome);
Java methods use