When you need some sort of ordering for the classes which you define, you will be going either for a comparable or comparator interface. Consider this example package test; import java.util.*; public class TreeSetTest { private static Set<Person> s = new TreeSet<Person>(); public static void main(String a[]){ s.add(new Person(20)); s.add(new Person(30)); s.add(new Person(10)); s.add(new Person(50)); …
Quartz Job Scheduler – Example Code
In this section we are going to develop a simple Quartz Scheduler application with the help of Quartz framework. That will display Hello World Quartz Scheduler :date & time on the console window after specified time schedule. Before using Scheduler you have to instantiate it. For doing this some users may keep an instance of …
What is load on startup element in web.xml file
specify the order in which we want to initialize various Servlets. Like first initialize Servlet1 then Servlet2 and so on. This is accomplished by specifying a numeric value for the <load-on-startup> tag. <load-on-startup> tag specifies that the servlet should be loaded automatically when the web application is started. The value is a single positive integer, …
Hibernate XML configuration file example
What is super and this keyword in java?
keyword : this ‘this’ is used for pointing the current class instance. It can be used with variables or methods. Look into the following example: class Test{ private int i=10; public void m(){ System.out.println(this.i); } } In the above code this is used for the current instance. Since this is instance of a class it …
How to use BitWise shift operator in Java?
They are called shift operators and they operate by shifting the number of bits being specified as an operand in the operation. >> —> Right shift Operator << —> Left Shift Operator >>> —-> Right bit with zero fill operator. The first two maintain the MSB when shifting thereby they maintain the sign of the …
List of Hibernate SQL Dialects
RDBMS Dialect DB2 org.hibernate.dialect.DB2Dialect DB2 AS/400 org.hibernate.dialect.DB2400Dialect DB2 OS390 org.hibernate.dialect.DB2390Dialect PostgreSQL org.hibernate.dialect.PostgreSQLDialect MySQL org.hibernate.dialect.MySQLDialect MySQL with InnoDB org.hibernate.dialect.MySQLInnoDBDialect MySQL with MyISAM org.hibernate.dialect.MySQLMyISAMDialect Oracle (any version) org.hibernate.dialect.OracleDialect Oracle 9i/10g org.hibernate.dialect.Oracle9Dialect Sybase org.hibernate.dialect.SybaseDialect Sybase Anywhere org.hibernate.dialect.SybaseAnywhereDialect Microsoft SQL Server org.hibernate.dialect.SQLServerDialect SAP DB org.hibernate.dialect.SAPDBDialect Informix org.hibernate.dialect.InformixDialect HypersonicSQL org.hibernate.dialect.HSQLDialect Ingres org.hibernate.dialect.IngresDialect Progress org.hibernate.dialect.ProgressDialect Mckoi SQL org.hibernate.dialect.MckoiDialect Interbase org.hibernate.dialect.InterbaseDialect Pointbase …
What is the difference between JRE,JVM and JDK?
If you are a Java developer, it is very often that you think about understanding the JRE,JVM and JDK. Once if you understand these things, it would be quite easy for you to visualize things in logical manner. Also look at the picture below, that will clear all your questions about the JRE,JVM and JDK. …