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The ELEMENTS of a GridBad layout are of equal SIZE and are LAID out using the squares of a grid.

The elements of a GridBad layout are of equal size and are laid out using the squares of a grid.

This() is used to INVOKE a CONSTRUCTOR of the same class. SUPER() is used to invoke a SUPERCLASS constructor.

This() is used to invoke a constructor of the same class. super() is used to invoke a superclass constructor.

JAVA is an object-oriented programming language developed initially by James Gosling and colleagues at Sun Microsystems. The language, initially called Oak (named after the oak trees outside Gosling's office), was intended to REPLACE C++, although the feature set better resembles that of Objective C. Java should not be CONFUSED with JavaScript, which shares only the NAME and a similar C-like SYNTAX. Sun Microsystems currently maintains and updates Java regularly.

Java is an object-oriented programming language developed initially by James Gosling and colleagues at Sun Microsystems. The language, initially called Oak (named after the oak trees outside Gosling's office), was intended to replace C++, although the feature set better resembles that of Objective C. Java should not be confused with JavaScript, which shares only the name and a similar C-like syntax. Sun Microsystems currently maintains and updates Java regularly.

A well-written OO program EXHIBITS RECURRING STRUCTURES that promote abstraction, flexibility, modularity and ELEGANCE.

A well-written OO program exhibits recurring structures that promote abstraction, flexibility, modularity and elegance.

Strategically speaking, threads CREATED by implementing Runnable interface are more advisable. If you create a THREAD by extending a thread CLASS, you cannot EXTEND any other class. If you create a thread by implementing Runnable interface, you save a space for your class to extend another class now or in future.

Strategically speaking, threads created by implementing Runnable interface are more advisable. If you create a thread by extending a thread class, you cannot extend any other class. If you create a thread by implementing Runnable interface, you save a space for your class to extend another class now or in future.

Yes, all functions in Java are virtual by default. This is ACTUALLY a pseudo trick question because the word "virtual" is not part of the naming CONVENTION in Java (as it is in C++, C-sharp and VB.NET), so this would be a foreign concept for someone who has only CODED in Java. Virtual functions or virtual methods are functions or methods that will be redefined in DERIVED classes.

Yes, all functions in Java are virtual by default. This is actually a pseudo trick question because the word "virtual" is not part of the naming convention in Java (as it is in C++, C-sharp and VB.NET), so this would be a foreign concept for someone who has only coded in Java. Virtual functions or virtual methods are functions or methods that will be redefined in derived classes.

The class SYSTEM has a VARIABLE out that represents the standard OUTPUT, and the variable err that represents the standard error device. By default, they both POINT at the system console. This how the standard output could be re-directed: 
Stream st = new Stream(new FILEOUTPUTSTREAM("output.txt")); System.setErr(st); System.setOut(st);

The class System has a variable out that represents the standard output, and the variable err that represents the standard error device. By default, they both point at the system console. This how the standard output could be re-directed: 
Stream st = new Stream(new FileOutputStream("output.txt")); System.setErr(st); System.setOut(st);

An abstract class may contain code in method bodies, which is not ALLOWED in an interface. With abstract classes, you have to INHERIT your class from it and Java does not allow multiple INHERITANCE. On the other HAND, you can implement multiple interfaces in your class.

An abstract class may contain code in method bodies, which is not allowed in an interface. With abstract classes, you have to inherit your class from it and Java does not allow multiple inheritance. On the other hand, you can implement multiple interfaces in your class.

Containers which USES BORDER Layout as their default are: window, FRAME and DIALOG classes.

Containers which uses Border Layout as their default are: window, Frame and Dialog classes.

Since EnterpriseBeans LIVE in a managed container, the container is FREE to call your EJB COMPONENTS methods at its LEISURE. The container houses the information like current status of bean,security credentials of the user currently accessing the bean in one object is called EJBContext Object. A context represents a way for beans to perform callbacks and modify their current status Sessioncontext is EJB context for session bean Entitycontext is EJB context for entity bean Message driven context is EJB context for message driven bean

Since EnterpriseBeans live in a managed container, the container is free to call your EJB components methods at its leisure. The container houses the information like current status of bean,security credentials of the user currently accessing the bean in one object is called EJBContext Object. A context represents a way for beans to perform callbacks and modify their current status Sessioncontext is EJB context for session bean Entitycontext is EJB context for entity bean Message driven context is EJB context for message driven bean

There is a pure division of roles between the TWO. Home INTERFACE is the way to communicate with the container which is responsible for creating , LOCATING and removing BEANS and Remote Interface is the link to the BEAN that allows acces to all methods and members.

There is a pure division of roles between the two. Home Interface is the way to communicate with the container which is responsible for creating , locating and removing beans and Remote Interface is the link to the bean that allows acces to all methods and members.

You shouldn’t. What will happen depends on the IMPLEMENTATION, but the CALL will most LIKELY be IGNORED.

You shouldn’t. What will happen depends on the implementation, but the call will most likely be ignored.

WHERE and ORDERBY CLAUSES are OPTIONAL in EJB QL where as SELECT and FROM are REQUIRED clauses.

WHERE and ORDERBY clauses are optional in EJB QL where as SELECT and FROM are required clauses.

Enterprise beans-An enterprise bean is a non-visual component of a distributed, transaction-oriented enterprise application. Enterprise beans are typically deployed in EJB containers and run on EJB servers.

There are three types of enterprise beans: session beans, entity beans, and message-driven beans.

1. Session beans: Session beans are non-persistent enterprise beans. They can be stateful or stateless. A stateful session bean acts on behalf of a single client and maintains client-specific session information (CALLED conversational STATE) across multiple method calls and transactions. It exists for the duration of a single client/server session. A stateless session bean, by comparison, does not maintain any conversational state. Stateless session beans are pooled by their container to handle multiple REQUESTS from multiple clients.
2. Entity beans: Entity beans are enterprise beans that contain persistent data and that can be saved in various persistent data stores. Each entity bean carries its own identity. Entity beans that MANAGE their own persistence are called bean-managed persistence (BMP) entity beans. Entity beans that delegate their persistence to their EJB container are called container-managed persistence (CMP) entity beans.
3. Message-driven beans: Message-driven beans are enterprise beans that receive and process JMS messages. Unlike session or entity beans, message-driven beans have no interfaces. They can be ACCESSED only through messaging and they do not maintain any conversational state. Message-driven beans allow asynchronous communication between the queue and the listener, and provide separation between message processing and business logic.

Enterprise beans-An enterprise bean is a non-visual component of a distributed, transaction-oriented enterprise application. Enterprise beans are typically deployed in EJB containers and run on EJB servers.

There are three types of enterprise beans: session beans, entity beans, and message-driven beans.

• Security support: Used to configure Deployment DESCRIPTOR (DD).
• Persistence support: Used to be persistence in transactions.
• Transaction management support: Used to configure Deployment Descriptor (DD).
• Management of SESSION: Callback methods such as ejbStore (), ejbLoad () are used in the DEVELOPER.
• Management of LIFE Cycle: Automatic

While both undergo activation and passivation; EB have ejbStore () callback to save STATE through passivation and ejbLoad () callback to load state through activation. But in case of SS, this is not needed because S.S.B FIELDS are serialized through objects by CONTAINERS.

While both undergo activation and passivation; EB have ejbStore () callback to save state through passivation and ejbLoad () callback to load state through activation. But in case of SS, this is not needed because S.S.B fields are serialized through objects by containers.

They are:

• MANDATORY
• REQUIRED
• REQUIRES_NEW
• SUPPORTS
• NOT_SUPPORTED
• NEVER

They are:

When “ONE to one” mapping is INVOLVED, and the data is STORED persistently is regional database, CMP is PREFERRED. But when no “one to one” mapping is there and data is retrieved from numerous tables having a complex query, Bean Managed Persistence is used.

When “one to one” mapping is involved, and the data is stored persistently is regional database, CMP is preferred. But when no “one to one” mapping is there and data is retrieved from numerous tables having a complex query, Bean Managed Persistence is used.

Session BEANS are used to shield the client from the complexity of the BUSINESS logic. They provide access to special transient business services. They are created by the client submitting the query to the database and exist as long as the client SERVER session exists.

Session bean components implement the javax.ejb.SessionBean interface. Client INVOKES the methods on the session beans to access the APPLICATION in the server.

Session beans are used to shield the client from the complexity of the business logic. They provide access to special transient business services. They are created by the client submitting the query to the database and exist as long as the client server session exists.

Session bean components implement the javax.ejb.SessionBean interface. Client invokes the methods on the session beans to access the application in the server.

They are:

• Session BEANS: EXPANDED as “Stateful”,”Stateless” and “SINGLETON”, A Remote or Local interface is used to access the EJB files.
• MESSAGE Driven Beans (MDB): Asynchronous execution by means of messaging paradigm is supported.

They are:

Between the client and the session bean, the state of the CONVERSATION can be maintained using a stateful session bean. The instance variables contain a state only during the invocation by a client method.

It implements ‘javax.ejb.SessionBean’ interface and is deployed with the declarative attribute ‘stateful’.

They have instance fields that can be initialized and modified by the client with each method invocation. The bean can use the conversational states as its BUSINESS PROCESS METHODS.

Between the client and the session bean, the state of the conversation can be maintained using a stateful session bean. The instance variables contain a state only during the invocation by a client method.

It implements ‘javax.ejb.SessionBean’ interface and is deployed with the declarative attribute ‘stateful’.

They have instance fields that can be initialized and modified by the client with each method invocation. The bean can use the conversational states as its business process methods.

EjbCreate () as being PART of the BEAN’s lifecycle, therefore, it is not MANDATORY for ejbCreate () method to be PRESENT and there will be no errors returned by the COMPILER.

EjbCreate () as being part of the bean’s lifecycle, therefore, it is not mandatory for ejbCreate () method to be present and there will be no errors returned by the compiler.

The create() METHOD is used to insert data into the database by creating a new instance of CMP entity bean. The CREATION methods look like this:

• ejbCreate()
• ejbPostCreate()

The creation methods are linked at run time. The CONTAINER delegates the invocation to these methods when the create() is invoked on home interface. These methods create Entity beans PER programmer specified parameters and CONDITIONS.

The create() method is used to insert data into the database by creating a new instance of CMP entity bean. The creation methods look like this:

The creation methods are linked at run time. The container delegates the invocation to these methods when the create() is invoked on home interface. These methods create Entity beans per programmer specified parameters and conditions.

EJB was TAKEN over by SUN Microsystems in 1999.

EJB was taken over by Sun Microsystems in 1999.

This is a method of binding a NAME to a SPECIFIC OBJECT by giving an interface LIKE javax.naming.Context

This is a method of binding a name to a specific object by giving an interface like javax.naming.Context

EJB was DEVELOPED by IBM in 1997.

EJB was developed by IBM in 1997.

EJB is a standard for developing server side in JAVA. It specifies agreement between COMPONENTS and application servers that allows components to run on server. They are mainly for complex serer side operations like executing complex ALGORITHM or high VOLUME business. EJB provides the application layer logic, also called as MIDDLE tier. It provides a standard specifications-based way to DEVELOP and deploy enterprise-class system.

EJB is a standard for developing server side in JAVA. It specifies agreement between components and application servers that allows components to run on server. They are mainly for complex serer side operations like executing complex algorithm or high volume business. EJB provides the application layer logic, also called as middle tier. It provides a standard specifications-based way to develop and deploy enterprise-class system.