Java Tutorial - 29 Methods in Java - StudyViral
Java Tutorial - 29 Methods in Java - StudyViral
A method is a set of code which is referred to by name and can be called (invoked) at any point in a program simply by utilizing the method's name.
Methods allow us to reuse the code without retyping the code.
The only required elements of a method declaration are the method's return type, name, a pair of parentheses, () , and a body between braces, {} .
The only required elements of a method declaration are the method's return type, name, a pair of parentheses,
(), and a body between braces, {}.More generally, method declarations have six components, in order:
- Modifiers—such as
public,private,protected - The return type—the data type of the value returned by the method, or
voidif the method does not return a value. - The method name—the rules for field names apply to method names as well, but the convention is a little different.
- The parameter list in parenthesis—a comma-delimited list of input
parameters, preceded by their data types, enclosed by parentheses,
(). If there are no parameters, you must use empty parentheses. - An exception can be part of method header section after parentheses () and before opening brace {.
- The method body, enclosed between braces—the method's code, including the declaration of local variables, goes here.
Example :
public class DemoMethods {
//declaration of method
public static void myMethod() {
System.out.println("Hye it's my method");
}
//declaration of method
public void myMethod1() {
System.out.println("Hye now i need Object to call this method");
}
public static double adding1(double a, double b) {
double c = a+b;//30
return c;
}
//declaration of method
public int adding2(int a,int b,int c) {
int d = a+b+c;//17
return d;
}
public static void main(String[] args) {
myMethod();//calling
DemoMethods dm = new DemoMethods();
dm.myMethod1();
System.out.println("Retutn double :: "+adding1(10.0,20.0));
System.out.println("Retutn int :: "+dm.adding2(5,4,8));
}
}
Java Tutorial - 28 Constructor in Java - StudyViral
Java Tutorial - 28 Constructor in Java - StudyViral
Constructors
In Java Constructors are special methods which has the same name as class name.
It also helps to initialize the object of a class.
The new operator is used with constructor.
If we don't specify constructor than java compiler automatically provide it, we can also say Constructor is implicitly called by Java Compiler.
Constructor don't have return type.
There are two type of constructors in java.
1). Default constructor.
2). Parameterized Constructor.
Java Swing Tutorials (GUI) - Read and Write JList with Text File - Study Viral
Java Swing Tutorials (GUI) - Read and Write JList with Text File - Study Viral
In this video I am going to show You
1). Write data from JList to text file
2). Load/Add data to JList from text file
There are number of classes we can use
For this video we need
Save To File
we can use FileWriter but the problem is it don't allow new line character
BufferedWriter is used to read data
but i am using PrintWriter to write on text file because it has println()
Read From File
FileWriter - makes it possible to read the contents of a file as a stream
of characters.
BufferedReader - that reads text from a character-input stream,
buffering characters so as to provide for the efficient reading of
characters, lines and arrays.
Java Swing (GUI) - Update JList Data - Study Vira
Java Swing (GUI) - Update JList Data - Study Viral
In this video i am updating JList on runtime
after add data we select data from jlist
Now Update Selected Value from jtextfield to jlist
This thing add extra element to list
Now we need to remove selected index element also
Please Do Subscribe my Channel
Have A Nice Day :D
Java GUI - JList (Java Swing) Using Netbeans Part 02 - Study Viral
Java GUI - JList (Java Swing) Using Netbeans Part 02 - Study Viral
Now the Coding Part
1. Close button and Minimize Button
2. Button Color on Mouse Entered & Exit
3. Add button Code to add data to list
4. Simple click operation on jtextfield to clear msg
5. Increase Counter
6. Remove Data but before that we need to find index of jlist data which we
going to remove for that click operation on jlist
7. Now Remove data only when user select data from list
