Java J2ee Planet

What is Cluster? Ans: A cluster is a group of queue managers set up in such a way that the queue managers can communicate directly with one another over a single network, without the need for transmission queue, channel, and remote queue definitions.   Some important MQSC commands that work with cluster DISPLAY CLUSQMGR SUSPEND CLUSQMGR RESUME CLUSQMGR REFRESH CLUSTER RESET CLUSTER     What are the Advantages of clustering? Advantages: Reduced system administration Increased high availability Improved resource utilization Workload sharing What is the algorithm that is followed by MQ in clustering? Ans: WebSphere MQ uses a workload management algorithm that uses a round-robin routine to select an available queue manager to route a message to.   What is Cluster queue manager? A cluster Queue manager is a queue manager that is a member of a cluster. A queue manager can be a member of more than one cluster   What happe...

What is MQ and what does it do? Ans. MQ stands for MESSAGE QUEUEING. WebSphere MQ allows application programs to use message queuing to participate in message-driven processing. Application programs can communicate across different platforms by using the appropriate message queuing software products. What is Message driven process? Ans . When messages arrive on a queue, they can automatically start an application using triggering . If necessary, the applications can be stopped when the message (or messages) have been processed. What are advantages of the MQ? Ans. 1. Integration. 2. Asynchrony 3. Assured Delivery 4. Scalability. How does it support the Integration? Ans . Because the MQ is independent of the Operating System you use i.e. it may be Windows, Solaris,AIX.It is independent of the protocol (i.e. TCP/IP, LU6.2, SNA, NetBIOS, UDP).It is not required that both the sender and receiver should be running on the same platform

Explain the user defined Exceptions? User defined Exceptions are custom Exception classes defined by the user for specific purpose. A user defined exception can be created by simply sub-classing an Exception class or a subclass of an Exception class. This allows custom exceptions to be generated (using throw clause) and caught in the same way as normal exceptions. Example: class CustomException extends Exception { } What classes of exceptions may be caught by a catch clause? A catch clause can catch any exception that may be assigned to the Throwable type. This includes the Error and Exception types. Errors are generally irrecoverable conditions What is the difference between exception and error? Error's are irrecoverable exceptions. Usually a program terminates when an error is encountered. What is the difference between throw and throws keywords? The throw keyword denotes a statement that causes an exception to be initiated. It takes the Exception object to be thrown as an a...

What are three ways in which a thread can enter the waiting state? Or What are different ways in which a thread can enter the waiting state? A thread can enter the waiting state by the following ways: 1. Invoking its sleep() method, 2. By blocking on I/O 3. By unsuccessfully attempting to acquire an object's lock 4. By invoking an object's wait() method. 5. It can also enter the waiting state by invoking its (deprecated) suspend() method. What is the difference between yielding and sleeping? When a task invokes its yield() method, it returns to the ready state, either from waiting, running or after its creation. When a task invokes its sleep() method, it returns to the waiting state from a running state. How to create multithreaded program? Explain different ways of using thread? When a thread is created and started, what is its initial state? Or Extending Thread class or implementing Runnable Interface. Which is better? You have two ways to do so. First, making you...

Serialization is another important topic that needs to be well prepared whe n you are going fro interview. We have collected important topics that are asked by interview panel of one of the major companies. Just check them below How many methods in the Serializable interface? Which methods of Serializable interface should I implement? There is no method in the Serializable interface. It’s an empty interface which does not contain any methods. The Serializable interface acts as a marker, telling the object serialization tools that the class is serializable. So we do not implement any methods.  What is the difference between Serializalble and Externalizable interface? How can you control over the serialization process i.e. how can you customize the seralization process? When you use Serializable interface, your class is serialized automatically by default. But you can override writeObject() and readObject() two methods to control more complex object serailization process. When ...

Maven, a Yiddish word meaning accumulator of knowledge, was originally started as an attempt to simplify the build processes in the Jakarta Turbine project. There were several projects each with their own Ant build files that were all slightly different and JARs were checked into CVS. We wanted a standard way to build the projects, a clear definition of what the project consisted of, an easy way to publish project information and a way to share JARs across several projects. The result is a tool that can now be used for building and managing any Java-based project. We hope that we have created something that will make the day-to-day work of Java developers easier and generally help with the comprehension of any Java-based project. Maven's Objectives Maven's primary goal is to allow a developer to comprehend the complete state of a development effort in the shortest period of time. In order to attain this goal there are several areas of concern that Maven attempts to deal wi...

For any java professional Collections Framework is important subject to be expert in it. Since these concepts are used all most all business logics. Wherver the Java interview happens, interviewer expects you should be 40% of technical skills from Collections framework. So you should be perfect in In this subject. I have collected some of the very important and gunshot questions that have been asked most of the interviews in all major companies. I discussed with many guys who has gone for java interviews and collected these Java Collections Framework Questions & Answers. Just check them out.