Programming Articles - Page 2899 of 3366

In addition to the modules and packages built in to the standard distribution of Python, large number of packages from third party developers are uploaded to Python package repository called Python Package Index (https://pypi.org/. To install packages from here, pip utility is needed. The pip tool is an independent project, but since Python 3.4, it has been bootstrapped in Python distribution.The ensurepip module provides support for bootstrapping pip in existing installation of Python. Normally user doesn't need to use it explicitly. If however, installation of pip is skipped in normal installation or virtual environment, it may be needed.Following command will ... Read More

We will see here how to display all tables inside a MySQL database using Java. You can use show command from MySQL to get all tables inside a MySQL database.Let’s say our database is ‘test’. The Java code is as follows to show all table names inside a database ‘test’.The Java code is as follows. Here, connection is established between MySQL and Java −import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import com.mysql.jdbc.Connection; import com.mysql.jdbc.DatabaseMetaData; public class GetAllTables {    public static void main(String[] args) throws SQLException {       Connection conn = null;       try { ... Read More

Use the put() method to add elements to LinkedHashMap collection.First, let us create a LinkedHashMap −LinkedHashMap l = new LinkedHashMap();Now, add elements −l.put("1", "Jack"); l.put("2", "Tom"); l.put("3", "Jimmy"); l.put("4", "Morgan"); l.put("5", "Tim"); l.put("6", "Brad");The following is an example to add elements to LinkedHashMap collection −Example Live Demoimport java.util.LinkedHashMap; public class Demo { public static void main(String[] args) { LinkedHashMap l = new LinkedHashMap(); l.put("1", "Jack"); l.put("2", "Tom"); l.put("3", "Jimmy"); ... Read More

Firstly, create a HashMap −HashMap hm = new HashMap();Add some elements to the HashMap −hm.put("Shirts", new Integer(700)); hm.put("Trousers", new Integer(600)); hm.put("Jeans", new Integer(1200)); hm.put("Android TV", new Integer(450)); hm.put("Air Purifiers", new Integer(300)); hm.put("Food Processors", new Integer(950));Now, sort the HashMap based on keys using TreeMap −Map sort = new TreeMap(hm); System.out.println("Sorted Map based on key = "+sort);The following is an example to sort HasMap based on keys −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { HashMap hm = new HashMap(); hm.put("Shirts", new ... Read More

In this article, we will learn how to use the contains() method in Java's HashSet class to check whether specific elements are present in a set. We'll create a HashSet, add some elements to it, and verify the existence of given elements using the contains() method. Problem Statement Write a Java program to check if a specific element exists in a HashSet using the contains() method. Below is the demostration of the same − Input Elements in set = [33, 66, 67, 54, 88, 90, 30, 79] Output Elements in set = [33, 66, 67, 54, 88, 90, 30, 79] ... Read More

The synchronizedSet() method returns a synchronized (thread-safe) sorted set backed by the specified sorted set.First, create a HashSet and add elements −Set hs = new HashSet(); hs.add(29); hs.add(879); hs.add(88); hs.add(788); hs.add(456);Now, to get synchronized set, use the synchronizedSet() method −Set s = Collections.synchronizedSet(hs);The following is an example to get synchronized set from HashSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { Set hs = new HashSet(); hs.add(29); hs.add(879); ... Read More

To get enumeration over HashSet, first declare the HashSet and add elements −HashSet hs = new HashSet(); hs.add("P"); hs.add("Q"); hs.add("R");To get enumeration −Enumeration e = Collections.enumeration(hs);The following is an example to get Enumeration over HashSet −Example Live Demoimport java.util.*; public class Demo {    public static void main(String[] args) {       HashSet hs = new HashSet();       hs.add("P");       hs.add("Q");       hs.add("R");       Enumeration e = Collections.enumeration(hs);       while (e.hasMoreElements())       System.out.println(e.nextElement()); } }OutputP Q R

To get the minimum element of HashSet, use the Collections.min() method.Declare the HashSet −Set hs = new HashSet();Now let us add the elements −hs.add(29); hs.add(879); hs.add(88); hs.add(788); hs.add(456);Let us now get the minimum element −Object obj = Collections.min(hs);The following is an example to find the minimum element of HashSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { // create hash set Set hs = new HashSet(); hs.add(29); hs.add(879); ... Read More

To check whether an element is in a HashSet or not in Java, use the contains() method.Create a HashSet −HashSet hs = new HashSet();Add elements to it −hs.add("R"); hs.add("S"); hs.add("T"); hs.add("V"); hs.add("W"); hs.add("Y"); hs.add("Z");To check for an element, for example, S here, use the contains() −hs.contains("S")The following is an example to check for an element in a HashSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { HashSet hs = new HashSet(); // add elements to the HashSet ... Read More

To remove a single element from a HashSet, use the remove() method.First, create a HashSet −HashSet hs = new HashSet();Now, add elements to the HashSet −hs.add("R"); hs.add("S"); hs.add("T"); hs.add("V"); hs.add("W"); hs.add("Y"); hs.add("Z");Let us now remove an element −hs.remove("R");The following is an example to remove a single element from a HashSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { HashSet hs = new HashSet(); // add elements to the hash set hs.add("R"); ... Read More