Java Programming

class in which objects can be created is called as concrete class.

Which Pascal compiler do you mean? Pascal compiler can be written in Pascal, of course.

1.user defined packages

2.predefined packages

The ability to modify a scheme definition in one level without affecting a scheme definition in next higher level is called data independence

there are two types of data independence

physical data independence:- refers to the ability to modify the scheme followed at the physical level without affecting the scheme followed at logical level

logical data independence:- refers to the ability to modify the conceptual scheme without affecting the schemes followed at view level

logical independence is difficult to achieve

If you mark an instance variable as transient, you're telling the JVM to skip (ignore) this variable when you attempt to serialize the object containing it. Don't worry about Serialization just yet. That is a cool feature of java that we shall be seeing in greater detail in one of the subsequent chapters. For not it is enough to know that a transient variable will be ignored when the object is serialized.

In Java, you cannot compile an interface directly because interfaces themselves are not executable; they are meant to define a contract for classes that implement them. However, you can compile the interface along with the implementing classes. When you compile a Java program, the Java compiler generates bytecode for all classes and interfaces, which can then be executed by the Java Virtual Machine (JVM).

J2EE, or Java 2 Platform, Enterprise Edition, is a set of specifications from Sun Microsystems (now part of Oracle) that extends the Java SE (Standard Edition) with specifications for enterprise features such as distributed computing and web services. It provides a robust environment for developing and deploying large-scale applications, particularly those that require scalability, reliability, and security. J2EE includes technologies like Servlets, JSP (JavaServer Pages), EJB (Enterprise JavaBeans), and more, facilitating the development of multi-tiered, web-based applications.

An immediate exception refers to a situation where an error or anomaly occurs in a system or process that requires urgent attention and resolution. This can happen in various contexts, such as programming, where an immediate exception might halt the execution of a program until the issue is addressed. It often indicates a critical failure that cannot be ignored, necessitating prompt intervention to restore normal functionality.

Methods that are neither mutators (setters) or accessors (getters). This primarily includes the class constructors (the initialisers) and the class destructor (the restorer).

Java Enterprise Edition (Java EE).

sOutput has the value "12.3" (the string representation of 12.3f).

You add up all the array elements, then divide by the number of elements. You can use a nested for() loop in Java; inside the inner for() loop, you can both increase a counter (to count how many elements there are), and add to a "sum" variable.

To arrange numbers in ascending order using Java, you can utilize the Scanner class to read input from the user and then sort the numbers using an array. Here's a simple example:

import java.util.Arrays;
import java.util.Scanner;

public class AscendingOrder {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the number of elements: ");
        int n = scanner.nextInt();
        int[] numbers = new int[n];

        System.out.println("Enter the numbers:");
        for (int i = 0; i < n; i++) {
            numbers[i] = scanner.nextInt();
        }

        Arrays.sort(numbers);
        System.out.println("Numbers in ascending order: " + Arrays.toString(numbers));
        scanner.close();
    }
}

This program collects a specified number of integers from the user, sorts them using Arrays.sort(), and then displays the sorted list.

A Scenario where one class is inheriting/extending the behavior of just one super class.

Ex: public class Ferrari extends Car {…}

Here the Ferrari class is using features/logic from the Car class

Sea Pole class bathyscaphe was created in 2009.

SER R class was created in 1888.

Scenes from the Class Struggle in Springfield was created on 1996-02-04.

Exception to the Rule was created on 1997-04-05.

Getter method: A getter method have its name start with 'get', and take 0 parameters, and also returns a value. Setter method: A setter method have its name start with "set", and takes 1 parameter. Setters may or may not return a value. Some setters return void, some the value set.

That means: the file where a class is stored.

A pointer variable contains the address to some memory location. "Dereferencing" the pointer means getting the value stored at that memory location.

The String class is part of java.langpackage which is automatically and implicitly imported in all classes. In other words, adding the statement "import java.lang.String" is redundant.