You can remove a particular record from a table in a database using the DELETE query.SyntaxDELETE FROM table_name WHERE [condition];To delete a record from a table using JDBC API you need to:Register the driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password (String) as parameters to it.Create Statement: Create a Statement object using the createStatement() method of the Connection interface.Execute the Query: Execute the query using the executeUpdate() method of ... Read More

A. You can update/modify the existing contents of a record in a table using the UPDATE query. Using this you can update all the records of the table or specific records.SyntaxUPDATE table_name SET column1 = value1, column2 = value2...., columnN = valueN WHERE [condition];To update the contents of a record in a table using JDBC API you need to:Register the driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password ... Read More

A. You can read/fetch the contents of a record in a table using the SELECT query. This will return data in the form of a result table and, these result tables are called result-sets.SyntaxSELECT column1, column2, columnN FROM table_name; Or, SELECT * FROM table_name;To retrieve the contents of a row of a table using JDBC API you need to:Register the driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password ... Read More

A. You can insert records in to a table using the INSERT query.SyntaxINSERT INTO TABLE_NAME (column1, column2, column3, ...columnN) VALUES (value1, value2, value3, ...valueN); Or, INSERT INTO TABLE_NAME VALUES (value1, value2, value3, ...valueN);To insert a record into a table in a database using JDBC API you need to:Register the driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password (String) as parameters to it.Create Statement: Create a Statement object using ... Read More

A. You can drop/delete a database using the DROP DATABASE query.SyntaxDROP DATABASE DatabaseName;To drop a Database using JDBC API you need to:Register the driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password (String) as parameters to it.Create Statement: Create a Statement object using the createStatement() method of the Connection interface.Execute the Query: Execute the query using the execute() method of the Statement interface.ExampleThe show databases command gives ... Read More

To add elements to the ArrayBlockingQueue class, use the add() method.The syntax is as follows:boolean add(E ele)Here, ele is the element to be added to the queue.To work with ArrayBlockingQueue class, you need to import the following package:import java.util.concurrent.ArrayBlockingQueue;The following is an example to add elements in Java ArrayBlockingQueue class:Example Live Demoimport java.util.concurrent.ArrayBlockingQueue; public class Demo {    public static void main(String[] args) {       ArrayBlockingQueue q = new ArrayBlockingQueue(7);       q.add(100);       q.add(250);       q.add(300);       q.add(450);       q.add(550);       q.add(600);       q.add(700);   ... Read More

To return a shallow copy of the CopyOnWriteArrayList, use the clone() method.The syntax is as follows:public Object clone()To work with CopyOnWriteArrayList class, you need to import the following package:import java.util.concurrent.CopyOnWriteArrayList;The following is an example to implement CopyOnWriteArrayList class clone() method in Java:Example Live Demoimport java.util.concurrent.CopyOnWriteArrayList; public class Demo {    public static void main(String[] args) {       CopyOnWriteArrayList arrList = new CopyOnWriteArrayList();       arrList.add(30);       arrList.add(90);       arrList.add(80);       arrList.add(70);       arrList.add(90);       arrList.add(100);       arrList.add(120);       System.out.println("CopyOnWriteArrayList = " + arrList);       System.out.println("Cloned CopyOnWriteArrayList = " + arrList.clone());    } }OutputCopyOnWriteArrayList = [30, 90, 80, 70, 90, 100, 120] Cloned CopyOnWriteArrayList = [30, 90, 80, 70, 90, 100, 120]

The poll() method of the ArrayBlockingQueue class in Java retrieves and removes the head of this queue, or returns null if this queue is empty.The syntax is as follows:E poll()To work with ArrayBlockingQueue class, you need to import the following package:import java.util.concurrent.ArrayBlockingQueue;The following is an example to implement poll() method of Java ArrayBlockingQueue class:Example Live Demoimport java.util.concurrent.ArrayBlockingQueue; public class Demo {    public static void main(String[] args) throws InterruptedException {       ArrayBlockingQueue q = new ArrayBlockingQueue(10);       q.add(200);       q.add(310);         q.add(400);       q.add(450);       q.add(500);     ... Read More

The empty() method of the DoubleStream class in Java returns an empty sequential DoubleStream.The syntax is as follows:static DoubleStream empty()To use the DoubleStream class in Java, import the following package:import java.util.stream.DoubleStream;Let us create an empty DoubleStream:DoubleStream doubleStream = DoubleStream.empty();Now, let us check the number of elements in the stream. It will be 0, since the stream is set to empty:doubleStream.count()The following is an example to implement DoubleStream empty() method in Java:Example Live Demoimport java.util.stream.DoubleStream; public class Demo {    public static void main(String[] args) {       DoubleStream doubleStream = DoubleStream.empty();       System.out.println("Number of elements in the stream ... Read More

The toArray() method returns an array containing the elements of this stream.The syntax is as follows:double[] toArray()To use the DoubleStream class in Java, import the following package:import java.util.stream.DoubleStream;Create DoubleStream and add some elements:DoubleStream doubleStream = DoubleStream.of(20.7, 30.5, 45.9, 60.2, 75.9, 88.3, 95.2);Now, use the toArray() method to return an array with the stream elements:double[] myArr = doubleStream.toArray();The following is an example to implement DoubleStream toArray() method in Java:Example Live Demoimport java.util.*; import java.util.stream.DoubleStream; public class Demo {    public static void main(String[] args) {       DoubleStream doubleStream = DoubleStream.of(20.7, 30.5, 45.9, 60.2, 75.9, 88.3, 95.2);       double[] ... Read More