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Find Elements Above Average in Java Arrays

The problem is to write a program that finds the number of the items above the average of all items. Now you can write a program using arrays to solve the problem, the problem is to read 100 numbers, get the average of these numbers, and find the number of the items greater than the average. To be flexible for handling any number of inputs, we will let the user enter the number of inputs, rather…

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Avoid Common Java Array Mistakes: Use Foreach Loops

Java support a convenient for loop, Known as a foreach loop, which enables you to traverse the array sequentially without using an index variable. For example, the following code displays all the elements in the array myList: for (double e: myList){ System.out.print(e); } You can read the code as “for each element e in myList, do the following”. Note that the variable, e, must be declared as…

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Java Array Initialization Techniques Explained

When processing array elements, you will often use a for loop for one of two reasons: 1- All of the elements in an array are of the same type. They are evenly processed in the same fashion repeatedly using a loop. 2- Since the size of the array is known, it is natural to use a for loop. Assume that the array is created as follows : double [] myList = new double [10]; The following are some…

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Java Array Initialization and Syntax Tips

When space for an array is allocated, the array size must be given, specifying the number of elements that can be stored in it. The size of an array cannot be changed after the array is created. Size can be obtained using arrayRefVar.length. For example, myList.length is 10. When an array is created, it’s elements are assigned the default value of 0 for the numeric primitive data types, \u0000…

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How to Declare and Create Arrays in Java

A single array variable can reference a large collection of data. Often you will have to store a large number of values during the execution of a program. Suppose ,for instance, that you need to read 100 numbers, compute their average, and find out how many numbers are above the average. Your program first reads the numbers and compute their average, then compares each number with the average to…

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Benefits of Stepwise Refinement in Programming

Stepwise refinement breaks a large problem into smaller manageable subproblems. Each subproblem can be implement breaks it into smaller methods. This apporach makes the program easier to write, reuse, debuge, test, modify, and maintain. Simpler Program: The print calendar program is long. Rather than writing a long sequence of statements in one method, stepwise refinement breaks it into smaller…

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Understanding Method Abstraction in Software Development

The key to developing software is to apply the concept of abstraction. Method abstraction is achieved by separating the use of a method from its implementation. The client can use a method without knowing how it is implemented. The details of the implementation are encapsulated in the method and hidden from the client who invokes the method. This is also known as information hiding or…

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Generate Random Characters in Java: A Simple Guide

A character is coded using integer. Generating a random character is to generate an integer. Computer programs process numerical data and characters. You have seen many examples that involve numerical data. It is also important to understand characters and how to process them. Every character has a unique unicode between 0 and FFFF in hexadecimal (65535 in decimal ). To generate a random…

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Local Variables: Definition and Scope Explained

The scope of a variable is the part of the program where the variable can be referenced. A variable defined inside a method is referred to as a local variable. The scope of a local variable starts from its declaration and continues to the end of the block that contains the variable. A local variable must be declared and assigned a value before it can be used. A parameter is actually a local…

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Understanding Method Overloading in Java

Overloading methods enable you to define the methods with the same name as long as their parameters lists are different. The max method used earlier works only with the int data type. But what if you need to determine which of the two floating-point numbers has the maximum value? The solution is to create another method with the same name but different parameters, as shown in the following…

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Hex to Decimal Conversion Explained with Java Code

This program converts a hexadecimal number into a decimal number. How would you convert a hex number into a decimal? Given a hexadecimal number hn hn-1hn-2 …h2 h1 h0 , the equivalent decimal value is h2*16n + hn-1 *16n-1 +…+h0 *160 For example, the hex number AB8C is: 10 * 163 + 11*162 + 8 *161 + 12 * 160 = 43916. Our program will prompt the user to enter a hex number as a string and convert…

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Efficient Prime Number Generation in Java

public class PrimeNumberMethod { public static void main(String[] args) { System.out.println("The first 50 prime numbers are \n"); printPrimeNumbers(50); } public static void printPrimeNumbers(int numberOfPrimes){ final int NUMBER_OF_PRIMES_PER_LINE = 10; // Display 10 per line int count = 0; // Count the number of prime numbers int number = 2; // A number to be tested for primeness //…

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Modular Code: Benefits of Reusing Methods in Java

Modularizing makes the code easy to maintain and debug and enables the code to be reused. Methods can be used to reduce redundant code and enable code reuse. Methods can also be used to modularize code and improve the quality of the program. import java.util.Scanner; public class GreatestCommonDivisorMethod { /** Main method */ public static void main(String[] args) { // Create a…

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Java Method Parameters: Argument Passing Explained

The arguments are passed by value to parameters when invoking a method. The power of a method is its ability to work with parameters. You can use println to print any string, and max to find the maximum of any two int values. When calling a method, you need to provide arguments, which must be given in the same order as their respective parameters in the method signature. This is known as…

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Difference Between Void and Return Methods in Java

A void method does not return a value. public class TestVoidMethod { public static void main(String[] args) { System.out.print("The grade is "); printGrade(78.5); System.out.print("The grade is "); printGrade(59.5); } public static void printGrade(double score){ if (score >= 90.0) { System.out.println('A'); } else if (score >= 80.0) { System.out.println('B'); } else if (score >= 70.0)…

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How to Call Methods in Java Effectively

Calling a method executes the code in the method. In a method definition, you define what the method id to do. To execute the method, you have to call or invoke it. The program that calls the function is called caller. There are two ways to call a method, depending on whether the method returns a value or not. If a method returns a value, a call to the method is usually treated as a value. For…

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Java Method Tutorial: Organize Your Code Efficiently

Methods can be used to define reusable code and organize and simplify coding. Suppose you need to find the sum of integers from 1 to 10, 20 to 37, and 35 to 49, respectively. you may write the code as follows: int sum = 0; for (int i = 1; i<= 10; i++) sum+= i; System.out.println("Sum from 1 to 10 is" + sum); sum =0; for (int i =20; i<=37; i++) sum+= i; System.out.println("Sum from 20 to 37 is…