how to declare a variable in java code example

Example 1: Variables in java

// instance variable in java example
public class InstanceVariableDemo
{
   // instance variable declared inside the class and outside the method
   int c;
   public void subtract()
   {
      int x = 100;
      int y = 50;
      c = x - y;
      System.out.println("Subtraction: " + c);
   }
   public void multiply()
   {
      int m = 10;
      int n = 5;
      c = m * n;
      System.out.println("Multiplication: " + c);
   }
   public static void main(String[] args)
   {
      InstanceVariableDemo obj = new InstanceVariableDemo();
      obj.subtract();
      obj.multiply();
   }
}

Example 2: declare variables java

/* Depending on what variables you want to declare */
String hello = "hello"; //characters
short one = 12;//shorter integers
int two = 2000; //complete integer up too 32 bits
long number = 2000000; //complete integer up to 64 bits
float decimal = 1.512 //up to 7 decimal digits
double million = 1.387892847395 //up tp 16 decmial digits
Bool condition = true; // true or false
char a = "a"; // unicode character

Example 3: Variables in java

// static variable in java example
public class StaticVariableExample
{
   // static variable
   static int a = 0;
   public void add()
   {
      a++;
   }
   public static void main(String[] args)
   {
      StaticVariableExample obj1 = new StaticVariableExample();
      StaticVariableExample obj2 = new StaticVariableExample();
      obj1.add();
      obj2.add();
      // both objects are sharing same copy of static variable
      System.out.println("Object 1 value is: " + a);
      System.out.println("Object 2 value is: " + a);
   }
}

Example 4: Variables in java

// local variable in java example
public class LocalVariableExample
{
   public void employeeDetails()
   {
      // local variable empAge and name
      int empAge = 22;
      String name = "Sachin";
   }
   public static void main(String[] args)
   {
      LocalVariableExample obj = new LocalVariableExample();
      // name and empAge cannot 
      // be resolved to a variable
      System.out.println("Employee name is : " + name + ", and age : " + empAge);
   }
}

Example 5: java variables

/*
##	Variable
- Container which holds the value while the Java program is executed. 
- Assigned with a data type. 
- Name of memory location. 

##	There are three types of variables in java: 
1) Local variable 
2) Static (or class) variable 
3) Instance variable
*/