Programming Articles - Page 2200 of 2896

A library named OpenCSV provides API’s to read and write data from/into a.CSV file. Here it is explained how to read the contents of a .csv file using a Java program.Maven dependency    com.opencsv    opencsv    4.4    org.apache.commons    commons-lang3    3.9 The CSVReader class of the com.opencsv package represents a simple CSV reader. While instantiating this class you need to pass a Reader object representing the file to be read as a parameter to its constructor. It provides methods named readAll() and readNext() to read the contents of a .csv fileUsing the readNext() methodThe readNext() ... Read More

Using the File classThe class named File of the java.io package represents a file or directory (pathnames) in the system. This class provides various methods to perform various operations on files/directories.This class provides various methods to manipulate files, The rename() method of the File class accepts a String representing a destination file and, renames the abstract file path of the current file to the given one.This method actually moves the file from the source path to the destination path.Example Live Demoimport java.io.File; public class MovingFile {    public static void main(String args[]) {       //Creating a source file object ... Read More

The class named File of the java.io package represents a file or directory (pathnames) in the system. This class provides various methods to perform various operations on files/directories.To get the list of all the existing files in a directory this class provides five different methods to get the details of all files in a particular folder −String[] list()File[] listFiles()String[] list(FilenameFilter filter)File[] listFiles(FilenameFilter filter)File[] listFiles(FileFilter filter)The ListFiles() methodThis method returns an array holding the objects (abstract paths) of all the files (and directories) in the path represented by the current (File) object.The following Java program prints the name, path and, size ... Read More

To read a fixed number of elements from a file you can either read a required number of data elements from the file and process them or, read the entire file into a collection or an array and process it for every n element.ExampleFollowing Java program, reads the contents of a file 10 words at a time and prints them in a separate line.import java.io.File; import java.io.FileNotFoundException; import java.util.Scanner; public class ReadingData {    public static void main(String args[]) throws FileNotFoundException {       //Creating an object of the File to read data       File file = ... Read More

A JFrame is a subclass of Frame class and the components added to a frame are referred to as its contents, these are managed by the contentPane. We can add the components to a JFrame to use its contentPane instead. A JFrame is like a Window with border, title, and buttons. We can implement most of the java swing applications using JFrame.By default, a JFrame can be displayed at the top-left position of a screen. We can display the center position of JFrame using the setLocationRelativeTo() method of Window class.Syntaxpublic void setLocationRelativeTo(Component c)Exampleimport javax.swing.*; import java.awt.*; public class JFrameCenterPositionTest extends JFrame {    public JFrameCenterPositionTest() {     ... Read More

In this article, we will learn about the calculation of simple interest in Python 3.x. Or earlier.Simple interest is calculated by multiplying the daily interest rate by the principal amount by the number of days that elapse between the payments.Mathematically, Simple Interest = (P x T x R)/100 Where, P is the principal amount T is the time and R is the rateFor example, If P = 1000, R = 1, T = 2 Then SI=20.0 Now let’s see how we can implement a simple interest calculator in Python.Example Live DemoP = 1000 R = 1 T = 2 # simple ... Read More

In this article, we will learn about the Selection sort and its implementation in Python 3.x. Or earlier.In the selection sort algorithm, an array is sorted by recursively finding the minimum element from the unsorted part and inserting it at the beginning. Two subarrays are formed during the execution of Selection sort on a given array.The subarray, which is already sortedThe subarray, which is unsorted.During every iteration of selection sort, the minimum element from the unsorted subarray is popped and inserted into the sorted subarray.Let’s see the visual representation of the algorithm −Now let’s see the implementation of the algorithm ... Read More

In this article, we will learn about the solution to the problem statement given below −Problem statement − We are given a string, we have to remove the ith indexed character from the given string and display it.In any string in Python, indexing always starts from 0. Suppose we have a string “tutorialspoint” then its indexing will be done as shown below −T u t o r i a l s p o i n t 0 1 2 3 4 5 6 7 8 9 10 11 12 13Now let’s see the Python script for ... Read More

In this article, we will learn about the solution to the problem statement given below −Problem statement − Given a number n, we need to find the product of all of its unique prime factors available and return it.For example, Input: num = 11 Output: Product is 11 Explanation: Here, the input number is 11 having only 1 prime factor and it is 11. And hence their product is 11.Approach 1Using a for loop from i = 2 to n+1 check whether i is a factor of n & then check if i is the prime number itself, if yes ... Read More

A TreeSet is a subclass of AbstractSet class and it does not allow duplicate elements. By default, TreeSet stores the elements in an ascending order and retrieval speed of an element out of a TreeSet is faster. The TreeSet class internally uses a TreeMap to store elements. The elements in a TreeSet are sorted according to their natural ordering. We can also save the elements stored in a TreeSet to a file by using the Arrays.asList() method and pass this set as an argument to the writeObject() method of ObjectOutputStream class. Syntax public class TreeSet extends AbstractSet implements NavigableSet, Cloneable, Serializable Example import java.util.*; import java.io.*; public ... Read More