Complex numbers are expressed as the sum of a real number and an imaginary number. Its general form is ‘a + ib’ where a and b represent real numbers and ‘i’ an imaginary number. For example, 5.4 + 2.6i here, 5.4 is the real part and 2.6i is the imaginary part. The various application of complex number includes quantum mechanics, signal processing and so forth. In this article, we will create a Java program to add and subtract complex numbers using class. Although it supports almost all the basic mathematical operations. Program to Add and Subtract Complex Numbers using ... Read More

HashMap is a class that is used to implement Map Interface. It stores its element in key-value pairs. The Key is an object that is used to fetch and receive value associated with it. It has access to all the methods of Map Interface, it does not have any additional methods of its own. Duplicate values are not allowed, although we can store null values and keys. In this article, we will try reading the content of a local text file into Java HashMap. Java Program to Read Text File into Java HashMap The general syntax for HashMap is as ... Read More

Recursive Constructor Invocation is a compile time error that occurs when a constructor calls itself. It is similar to recursion where a method calls itself as often as necessary. The method that calls itself is called as recursive method and the constructor that calls itself is called as recursive constructor. In this article, we will understand the Recursive Constructor Invocation error in Java with a few examples. Recursive Constructor Invocation Constructor It is quite similar to methods but the difference is that methods define the behavior of an object but constructor is used to initialize those objects. We can provide ... Read More

Solving interesting pattern problems enhances the understanding of loops. They are essential because they help in building a strong foundation of a particular programming language. There are various kinds of patterns including number-based, star-based and alphabetical patterns as well. In this article, we will discuss a few Java programs to print interesting star patterns. Program to Print Interesting Pattern Pattern 1 Approach Declare and initialize an integer ‘n’ that specifies number of rows and columns. Define a for loop that will run till ‘n’. Inside this loop define an if-else block. The if block will print star ‘n’ ... Read More

Both StAX and SAX are a type of XML parser APIs. Here, API stands for Application Programming Interface and Parser is used to read and extract content from an XML document in desired format. From this line, it is clear that StAX and SAX are used to read XML documents. APIs are a modern way to migrate real time information on the Web. In this article, we will discuss the difference between StAX and SAX Parser in Java. StAX vs SAX Parser XML Its full form is eXtensible Markup Language and it is said to be a data description language. ... Read More

The TreeMap and TreeSet, both are the part of Collection Framework classes. There exist a few differences as well as a few similarities in their implementation and working. The TreeMap maintains key-value pair on the other hand the TreeSet does not have this feature. In this article, we will discuss the similarities between both classes of Collection Interface. Collection Interface In Java, collection is an object or we can say a container for simplicity that allows us to group several numbers of objects in a single unit. The collection interface is present at the root of all collection framework interfaces. ... Read More

Every time we do surfing on the Web or we download any file from Web, we take a risk of a virus attack. Maybe that file contains some malicious code that can breach the security and gain unauthorized access to system resources. If we are building an application that has users’ sensitive data, for example, a banking system contains confidential data like credit and debit card details, addresses, email and so forth. Then securing those data becomes our foremost priority. In this article, we are going to discuss a few standard practices for protecting the sensitive data of users in ... Read More

An array is a collection of elements of same data type, and each element in the array is identified by an index value. It is a simplest data structure and we can easily add or remove elements. Arrays in Python Python does not have a specific data structure to represent arrays. Here, we can use List an array. [9, 3, 1, 6, 9] We can use array or NumPy module to work with arrays in python. array('i', [1, 2, 3, 4]) The above array is the integer Array which is defined by the array module. In ... Read More

An array is a data structure consisting of a set of elements (values) of the same data type, each element is identified by an index value. And the elements can be directly accessed by using their index numbers. Arrays in Python Python does not have a native array data structure. Instead, we can use the list data structure, NumPy, or array modules. Here we will use list an array − [10, 4, 11, 76, 99] 0 1 2 3 4 The ... Read More

An array is a data structure consisting of a collection of elements of same data type, and each element is identified by an index. [2, 4, 0, 5, 8] 0 1 2 3 4 The integers 2, 4, 0, 5, 8 are the array elements and 0, 1, 2, 3, 4 are the respective index values of the array elements. In The article below, we will discuss the python program to find common elements between two arrays. Input Output Scenarios Assuming we have two arrays A and B. And the resultant ... Read More