Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Use the clone() method to copy all elements from one set to another.First HashSet −HashSet set = new HashSet (); set.add("One"); set.add("Two");Create another set and clone first set into the second −HashSet newSet = new HashSet ();Copy (clone) all elements to the second set −newSet = (HashSet)set.clone();The following is an example to copy all elements from one set to another −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { HashSet set = new HashSet (); HashSet newSet = new HashSet (); set.add("One"); ... Read More
To get the maximum element of HashSet, use the Collections.max() 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 maximum element −Object obj = Collections.max(hs);The following is an example to find maximum 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 know the biggest value from two or more fields, use the function GREATEST() from MySQL.The syntax is as follows −SELECT GREATEST(MAX(yourColumnName1), MAX(yourColumnName2), ...............MAX(yourColumnName2) ) from yourTableName;Let us understand the above concept by creating a table with more than two columns −mysql> create table GreatestOfTwoOrMore -> ( -> Marks1 int, -> Marks2 int, -> Marks3 int -> ); Query OK, 0 rows affected (0.57 sec)Here is the query to insert records in a table −mysql> insert into GreatestOfTwoOrMore values(23, 78, 89); Query OK, 1 row ... Read More
To get records from NOW()-1 Day, you can use the following syntax −select *from yourTableName where yourColumnName >=now()-interval 1 day;To understand the above syntax, let us first create a table. The query to create a table.mysql> create table GetRecordsFromNow −> ( −> YourDateTime datetime −> ); Query OK, 0 rows affected (1.76 sec)Now insert some dates into the fields. The query to insert records are as follows −mysql> insert into GetRecordsFromNow values(date_add(now(), interval 3 day)); Query OK, 1 row affected (0.28 sec) mysql> insert into GetRecordsFromNow values(date_add(now(), interval -1 day)); ... Read More
Use the containsKey() method and check if a given key exists in the HashMap or not.Let us first create HashMap and add some elements −// Create a hash map HashMap hm = new HashMap(); // Put elements to the map hm.put("Bag", new Integer(1100)); hm.put("Sunglasses", new Integer(2000)); hm.put("Frames", new Integer(800)); hm.put("Wallet", new Integer(700)); hm.put("Belt", new Integer(600));Now, let’s say we need to check whether the key “Bag” exists or not, For that, use the containsKey() method like this −hm.containsKey("Bag")The following is an example to check if a given key exists in HashMap −Example Live Demoimport java.util.*; public class Demo { ... Read More
To fetch LinkedHashSet key-value pair in Java, use the entrySet() method.Let us first create LinkedHashSet and add some elements −LinkedHashMap l = new LinkedHashMap(); l.put("1", "Jack"); l.put("2", "Tom"); l.put("3", "Jimmy"); l.put("4", "Morgan"); l.put("5", "Tim"); l.put("6", "Brad");Now, fetch a key-value pair −l.entrySet()The following is an example to fetch key-value pair from LinkedHashSet −Example Live Demoimport java.util.*; 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"); l.put("4", "Morgan"); l.put("5", "Tim"); ... Read More
To add AUTOINCREMENT in MySQL, you can use the ALTER command.ALTER TABLE yourTableName change yourColumName yourColumnName dataType AUTO_INCREMENT PRIMARY KEY;To understand the above concept, create a table with a column. Let us create a table −mysql> create table AlterTableToAddAutoIncrement -> ( -> StudentId int -> ); Query OK, 0 rows affected (0.57 sec)Implement the above syntax to change “StudentId” with AUTOINCREMENT. The query is as follows −mysql> alter table AlterTableToAddAutoIncrement change StudentId StudentId int AUTO_INCREMENT Primary key; Query OK, 0 rows affected (1.93 sec) Records: 0 Duplicates: 0 Warnings: 0We ... Read More
Let us create TreeMap in Java. It stores unique elements in ascending order −TreeMap m = new TreeMap();Now let us add some elements −m.put(1, "PHP"); m.put(2, "jQuery"); m.put(3, "JavaScript"); m.put(4, "Ruby"); m.put(5, "Java"); m.put(6, "AngularJS"); m.put(7, "ExpressJS");The following is an example to create a TreeMap −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { TreeMap m = new TreeMap(); m.put(1, "PHP"); m.put(2, "jQuery"); m.put(3, "JavaScript"); m.put(4, "Ruby"); m.put(5, "Java"); m.put(6, "AngularJS"); ... Read More
You cannot do select IN range. For the same result, use BETWEEN. Let us see an example −IN(start, end): It means that the intermediate value between start and end won’t get displayed. For the above logic, you can use BETWEEN.BETWEEN clause is inclusive, for example, suppose there are 1, 2, 3, 4, 5, 6 numbers. If you want to display numbers from 2 to 6 inclusively, then using BETWEEN the numbers 2 and 6 will also get displayed.Let us create a table −mysql> create table SelectInWithBetweenDemo -> ( -> PortalId int ... Read More
There are so many situations, that we should find android application is running background or not. This example demonstrates how to check if an android application is running background.Step 1 - Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 - Add the following code to res/layout/activity_main.xml. In the above layout, it contains text view, when the application is in foreground mode, it shows text view else you will get information in a log.Step 3 - Add the following code to src/MainActivity.javapackage ... Read More