J2SE Interview Questions and Answers 2

What is Boolean ?
Refers to an expression or variable that can have only a true or false value. The Java programming language provides the boolean type and the literal values true and false.

What is break ?
A Java keyword used to resume program execution at the statement immediately following the current statement. If followed by a label, the program resumes execution at the labeled statement.

What is bytecode ?
Machine-independent code generated by the Java compiler and executed by the Java interpreter.

What is case ?
A Java keyword that defines a group of statements to begin executing if a value specified matches the value defined by a preceding switch keyword.

What is casting ?
Explicit conversion from one data type to another.

What is catch ?
A Java keyword used to declare a block of statements to be executed in the event that a Java exception, or run time error, occurs in a preceding try block.

What is "abstract schema" ?
The part of an entity bean's deployment descriptor that defines the bean's persistent fields and relationships.

What is "abstract schema name" ?
A logical name that is referenced in EJB QL queries.

What is "access control" ?
The methods by which interactions with resources are limited to collections of users or programs for the purpose of enforcing integrity, confidentiality, or availability constraints.

What is "ACID" ?
The acronym for the four properties guaranteed by transactions: atomicity, consistency, isolation, and durability.

What is "activation" ?

The process of transferring an enterprise bean from secondary storage to memory. (See passivation.)

What is "anonymous access" ?
Accessing a resource without authentication.

What is class ?
In the Java programming language, a type that defines the implementation of a particular kind of object. A class definition defines instance and class variables and methods, as well as specifying the interfaces the class implements and the immediate superclass of the class. If the superclass is not explicitly specified, the superclass will implicitly be Object.

What is class method ?
A method that is invoked without reference to a particular object. Class methods affect the class as a whole, not a particular instance of the class. Also called a static method. See also instance method.

What is class variable ?
A data item associated with a particular class as a whole--not with particular instances of the class. Class variables are defined in class definitions. Also called a static field. See also instance variable.

What is classpath ?
An environmental variable which tells the Java virtual machine1 and Java technology-based applications where to find the class libraries, including user-defined class libraries.

What is client ?
In the client/server model of communications, the client is a process that remotely accesses resources of a compute server, such as compute power and large memory capacity.