Found 4332 Articles for Java 8

How to retrieve a record from an existing table in a database using JDBC API?

Vrundesha Joshi
Updated on 30-Jul-2019 22:30:25

782 Views

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

How to insert a record into a table in a database using JDBC API?

Jennifer Nicholas
Updated on 30-Jul-2019 22:30:25

1K+ Views

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

How to drop a database using JDBC API?

Nitya Raut
Updated on 30-Jul-2019 22:30:25

231 Views

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

How to add elements in Java ArrayBlockingQueue?

Krantik Chavan
Updated on 30-Jul-2019 22:30:25

76 Views

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

The clone() method of CopyOnWriteArrayList method in Java

Krantik Chavan
Updated on 30-Jul-2019 22:30:25

118 Views

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]

ArrayBlockingQueue poll() Method in Java

Krantik Chavan
Updated on 30-Jul-2019 22:30:25

109 Views

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

DoubleStream empty() method in Java

Krantik Chavan
Updated on 30-Jul-2019 22:30:25

32 Views

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

DoubleStream toArray() method in Java

Krantik Chavan
Updated on 30-Jul-2019 22:30:25

83 Views

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

LongStream findAny() method in Java

Daniol Thomas
Updated on 30-Jul-2019 22:30:25

64 Views

The findAny() method of the LongStream class in Java returns an OptionalLong describing some element of the stream, or an empty OptionalLong if the stream is empty.The syntax is as follows:OptionalLong findAny()Here, OptionalLong is a container object which may or may not contain a long value.To use the LongStream class in Java, import the following package:import java.util.stream.LongStream;The following is an example to implement LongStream findAny() method. The isPresent() method of the OptionalLong class returns true if the value is present:Exampleimport java.util.OptionalLong; import java.util.stream.LongStream; public class Demo {    public static void main(String[] args) {       LongStream longStream = ... Read More

Create Ennead Tuple using with() method in Java

Daniol Thomas
Updated on 30-Jul-2019 22:30:25

83 Views

To create Ennead Tuple, you can use the with() method. With that, you can also add elements to it. Let us first see what we need to work with JavaTuples. To work with Ennead class in JavaTuples, you need to import the following package:import org.javatuples.Ennead;Note: Download JavaTuples Jar library to run JavaTuples program. If you are using Eclipse IDE, then Right Click Project → Properties → Java Build Path → Add External Jars and upload the downloaded JavaTuples jar file. Refer the below guide for all the steps to run JavaTuples:Steps: How to run JavaTuples program in EclipseThe following is ... Read More

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