J2SE Interview Questions and Answers 9

What is JavaSafe ?
A tool for tracking and managing source file changes, written in Java.

What is JavaScript ?
A Web scripting language that is used in both browsers and Web servers. Like all scripting languages, it is used primarily to tie other components together or to accept user input.

What is JavaSpaces ?
A technology that provides distributed persistence and data exchange mechanisms for code in Java.

What is JDBC ?
Java Database Connectivity.

What is JDK ?
Java Development Kit. A software development environment for writing applets and application in Java .

What is JFC ?
Java Foundation Classes.

What is Jini Technology ?
A set of Java APIs that may be incorporated an optional package for any Java 2 Platform Edition. The Jini APIs enable transparent networking of devices and services and eliminates the need for system or network administration intervention by a user. The Jini technology is currently an optional package available on all Java platform editions.

What is JNDI ?
Java Naming and Directory Interface.

What is JNI ?
Java Native Interface.

What is JRE ?
Java Runtime Environment

What is Just-in-time (JIT) Compiler ?
A compiler that converts all of the bytecode into native machine code just as a Java program is run. This results in run-time speed improvements over code that is interpreted by a Java virtual machine.

What is JVM ?
Java Virtual Machine (JVM).

What is keyword ?
Java sets aside words as keywords - these words are reserved by the language itself and therefore are not available as names for variables or methods.

What is lexical ?
Pertaining to how the characters in source code are translated into tokens that the compiler can understand.

What is linker ?
A module that builds an executable, complete program from component machine code modules. The Java linker creates a runnable program from compiled classes. See also compiler, interpreter, runtime system.

What is literal ?
The basic representation of any integer, floating point, or character value. For example, 3.0 is a double-precision floating point literal, and "a" is a character literal.

What is local variable ?
A data item known within a block, but inaccessible to code outside the block. For example, any variable defined within a method is a local variable and can't be used outside the method.

What is long ?
A Java keyword used to define a variable of type long.