Programming Articles - Page 2552 of 3363

The default methods in an interface in Java are also known as defender methods or, virtual methods.The defender/virtual methods are those that will have a default implementation in an interface. You can define defender/virtual methods using the default keyword as −default void display() {    System.out.println("This is a default method"); }There is no need to implement these defender/virtual methods in the implementing classes you can call them directly.If you have an interface which is implemented by some classes and if you want to add a new method int it.Then, you need to implement this newly added method in all the ... Read More

You can create a table in a database using the CREATE TABLE query.SyntaxCREATE TABLE table_name( column1 datatype, column2 datatype, column3 datatype, ..... columnN datatype, PRIMARY KEY( one or more columns ) );To create 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 ... Read More

You can create a table in JavaDB database using the CREATE TABLE statement.SyntaxCREATE TABLE table_name (    column_name1 column_data_type1 constraint (optional),    column_name2 column_data_type2 constraint (optional),    column_name3 column_data_type3 constraint (optional) );To create a table in JavaDB using JDBC API you need to −Register the driver − The forName() method of the class, Class accepts a String value representing a class name loads it in to the memory, which automatically registers it. Register the driver using this method.Establish a connection − Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password (String) ... Read More

The java.sql.DriverManager class manages JDBC drivers in your application. This class maintains a list of required drivers and load them whenever it is initialized.Therefore, you need to register the driver class before using it. However, you need to do it only once per application.One way to register a driver class object to Driver manager is the registerDriver() method of the DriverManager class. To this method you need to pass the Driver object as a parameter.//Instantiating a driver class Driver driver = new com.mysql.jdbc.Driver(); //Registering the Driver DriverManager.registerDriver(driver);List of all the DriversYou can get the list of all the drivers registered ... Read More

The java.sql.DriverManager class manages JDBC drivers in your application. This class maintains a list of required drivers and load them whenever it is initialized.Therefore, you need to register the driver class before using it. However, you need to do it only once per application.You can register a new Driver class in two ways −Using the registerDriver() method of the DriverManager class. To this method you need to pass the Driver object as a parameter.//Instantiating a driver class Driver driver = new com.mysql.jdbc.Driver(); //Registering the Driver DriverManager.registerDriver(driver);Using the forName() method of the class named Class. To this method you need to ... Read More

CLOB stands for Character Large Object. in general, an SQL Clob is a built-in datatype which is used to store large amount of textual data. Using this datatype, you can store data up to 2, 147, 483, 647 characters. MYSQL database provides support Clob datatype TINYTEXT, TEXT, MEDIUMTEXT, LONGTEXT.The java.sql.Clob interface of the JDBC API represents the CLOB datatype. Since the Clob object in JDBC is implemented using an SQL locator, it holds a logical pointer to the SQL CLOB (not the data).Inserting Data into a column of Clob typeYou can insert a CLOB type value using the setCharacterStream() or, ... Read More

Clob datatypeCLOB stands for Character Large Object. in general, an SQL Clob is a built-in datatype which is used to store large amount of textual data. Using this datatype, you can store data up to 2, 147, 483, 647 characters. MYSQL database provides support Clob datatype TINYTEXT, TEXT, MEDIUMTEXT, LONGTEXT.The java.sql.Clob interface of the JDBC API represents the CLOB datatype. Since the Clob object in JDBC is implemented using an SQL locator, it holds a logical pointer to the SQL CLOB (not the data).Reading Data from a column of datatype ClobYou can read CLOB value (character stream data) from a ... Read More

You can get the properties of a driver using the getPropertyInfo() method of the Driver interface.DriverPropertyInfo[] info = driver.getPropertyInfo(mysqlUrl, null);This method accepts a two parameters: A String variable representing the URL of the database, an object of the class Properties and, returns an array of the DriverPropertyInfo objects, where each object holds information about the possible properties of the current driver.From a DriverPropertyInfo object you can get the information such as name of the property, value of the property, description, choices and, if it is required or not, using its fields name, value, description, choices, required, respectively.DriverPropertyInfo[] info = driver.getPropertyInfo(mysqlUrl, ... Read More

In this article, we will learn to close resources automatically in Java. Resource management becomes important in Java programming to prevent memory leaks and system instability. Java provides several options for closing resources automatically: files, database connections, and network sockets. The Problem with Manual Resource Closure Traditionally, developers needed to manually close resources using try-finally blocks. This method is error-prone because it's easy to forget to close resources, and exception handling can be complicated: FileInputStream fis = null; try { fis = new FileInputStream("file.txt"); } finally { if (fis != null) { ... Read More

Importing all methods from a module in Python is a bad idea because of the following reasons.It is difficult to find a parent module of the method which we used in the programs.We are not allowed to create our functions with the names of methods.Let's see an example. Below we write a function called add in the sample.py.## sample.py file def add(a, b): return a + bExampleSave the above file in the same directory as below Python file.## let's assume we have module called sample from sample import * def add(*nums):    return sum(nums) print(add(1, 2, 3, 4, ... Read More