Working with arrays : java.util.Arrays class


The java.util.Arrays class is basically a set of static methods that are all useful for working with arrays. The Arrays class contains various methods for manipulating arrays (such as sorting and searching). In addition to that, it has got many utility methods for using with arrays such as a method for viewing arrays as lists […]

How to use Enum in Switch?


Enums introduced in Java 5.0 (Read: New features in Java 5.0) allows switching to be done based on the enums values. It is one of the greatest new features introduced from the version 5.0. Prior to Java 1.4, switch only worked with int, short, char, and byte values. However, since enums have a finite set of […]

Adding methods to an Enum


Enums introduced in Java 5.0 are just compiled java classes with some extra behavior. So you can basically do whatever you can in a normal java class inside an enum as well. That includes adding methods , class level variables and constructors to an enum. Adding methods to an enum works just like adding methods […]

What is transient keyword in Java?


This article explains about the transient variable and when it will be used in the Java programming. Another important fact is that, this question is most frequently asked in the Java interviews for checking the basic knowledge of a programmer. Another point is that this keyword is not frequently used by programmer in the normal […]

Ordering Queue Using Comparator Interface and PriorityQueue


The basic use of Queue class is to provide a data structure which allows storing objects in a First in First out(FIFO) format. But sometimes one wants to maintain the ordering, based on some other metric. This is exactly the purpose of PriorityQueue, another Queue implementation. You provide it a Comparator, and it does the […]

load-on-startup element in web.xml


This tips explains the few points on how to use the load-on-startup element on the web.xml file. Whenever is starting, it is possible to tell the container to load a servlet on the startup. You can load any number of servlets on the startup. Normally this is done for any initialization purpose. Look into the […]

Flex 3.0 Applications with BlazeDS in Eclipse


Introduction BlazeDS is the server-based Java remoting and web messaging technology. BlazeDS enables Adobe Flex and Adobe AIR applications developers to easily connect to back-end distributed data and push data in real-time. BlazeDS makes use of AMF3 protocol which is similar to SOAP, but AMF3 protocol is a binary protocol and so is much faster […]

Servlets Interview Questions

1) Is it the “servlets” directory or the “servlet” directory? For Java Web Server: on the file system, it’s “servlets” c:\JavaWebServer1.1\servlets\DateServlet.class in a URL path, it’s “servlet” 2) How do I support both GET and POST protocol from the same Servlet? The easy way is, just support POST, then have your doGet method call […]

JDBC Interview Questions

1) I have the choice of manipulating database data using a byte[] or a java.sql.Blob. Which has best performance? java.sql.Blob, since it does not extract any data from the database until you explicitly ask it to. The Java platform 2 type Blob wraps a database locator (which is essentially a pointer to byte). That pointer […]

RMI Interview Questions

1)Explain RMI Architecture? RMI uses a layered architecture, each of the layers could be enhanced or replaced without affecting the rest of the system. The details of layers can be summarised as follows: Application Layer: The client and server program Stub & Skeleton Layer: Intercepts method calls made by the client/redirects these calls to a […]