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  package StringLearning; class Display { public static void print (String s) { System. out .println(s); } } public class StringFunc { public static void main (String[] args) { String s = "Java Programming" ; // Display original string Display. print (s); // Converts all characters to lower case Display. print ( "LowerCase: " + s.toLowerCase()); // Converts all characters to upper case Display. print ( "UpperCase: " + s.toUpperCase()); // Concatenates the specified string to the end of the original string Display. print ( "Concatenation: " + s.concat( " is easy." )); // Replaces each occurrence of a character with a new character Display. print ( "Replace 'a' with 'b': " + s.replace( 'a' , 'b' )); // Replaces each occurrence of a substring with a new substring Displ...

Java Program package LAB_Report; /* 2. Write a program in Java to demonstrate the usage of access modifiers: public, private, protected and default. */ class AccessModifier{ int defaultValue ; // this is visible within the package only public int publicValue ; // this is visible everywhere protected int protectedValue ; // this is visible within the package and subclasses private int privateValue ; // this is visible within the class only public void setPrivateValue ( int privateValue) { this . privateValue = privateValue; } public int getPrivateValue () { return privateValue ; } } class AccessModifierProtected extends AccessModifier{ public void setValue ( int value2){ this . protectedValue = value2; } public int getValue2 (){ return protectedValue ; } } public class Lab_2 { public static void main (String[] args) { AccessModifier am = new AccessModifier(); ...

  Inheritance is one of the fundamental concepts of Object-Oriented Programming (OOP) in Java. It allows a new class (child or subclass) to inherit the properties and behaviors (fields and methods) of an existing class (parent or superclass). This promotes code reuse and establishes a natural hierarchical relationship between classes. Types of Inheritance in Java Single Inheritance: A class inherits from one superclass. Multilevel Inheritance: A class inherits from another class, which in turn inherits from another class. Hierarchical Inheritance: Multiple classes inherit from one superclass. Note: Java does not support multiple inheritance (a class inheriting from more than one class) directly to avoid complexity and ambiguity. However, it can be achieved using interfaces. Examples of Inheritance Single Inheritance In single inheritance, a class inherits from one superclass. // Parent class class Vehicle { String brand = "Ford" ; void honk () { S...

Introduction Network Address Translation (NAT) is a fundamental technique used in networking to translate private IP addresses to public IP addresses and vice versa. Static NAT is a method where a specific private IP address is mapped to a specific public IP address.  Configuration Steps Router Configuration Enable NAT Service Router(config)# ip nat inside source static [inside-local] [inside-global] Replace [inside-local] with the private IP address to be translated. Replace [inside-global] with the public IP address to translate to. Configure Interfaces Router(config)# interface [inside-interface] Router(config-if)# ip address [inside-ip-address] [subnet-mask] Router(config-if)# ip nat inside Router(config-if)# no shutdown Router(config-if)# exit Router(config)# interface [outside-interface] Router(config-if)# ip address [outside-ip-address] [subnet-mask] Router(config-if)# ip nat outside Router(config-if)# no shutdown Router(config-if)# exit Replace [inside-interf...

What is the static Keyword? In Java, the static keyword is used to indicate that a particular member (variable or method) belongs to the class itself, rather than to instances of the class. This means that the static member can be accessed without creating an instance of the class. Static Variables A static variable is shared among all instances of a class. It is also known as a class variable. Example: public class Example { // static variable static int count = 0 ; Example() { count++; } public static void main (String[] args) { Example obj1 = new Example (); Example obj2 = new Example (); Example obj3 = new Example (); System.out.println( "Count: " + Example.count); // Output: Count: 3 } } In this example, the count variable is static and shared among all instances of the Example class. It keeps track of the number of instances created. Static Methods A static method belongs to ...

  What is a Method? In Java, a method is a block of code that performs a specific task. Methods are used to define the behavior of objects created from a class. They encapsulate code that can be reused and invoked whenever needed, making programs more modular and manageable. Defining a Method A method consists of a method declaration and a method body. The method declaration provides the method's name, return type, and parameters, while the method body contains the code to be executed. Syntax: returnType methodName (parameters) { // method body } Example: public class Example { // Method to add two numbers public int add ( int a, int b) { return a + b; } public static void main (String[] args) { Example example = new Example (); int sum = example.add( 5 , 3 ); System.out.println( "Sum: " + sum); // Output: Sum: 8 } } Method Components Access Modifiers: Define the visibility of the method (e....