Set - 5

Question 1 :

What is static method ?

Answer :

Another name for class method.

Question 2 :

What is stream ?

Answer :

A stream is simply a byte-stream of data that is sent from a sender to a receiver. There are two basic categories, so the package includes two abstract classes (InputStream and OutputStream).

Question 3 :

What is subclass ?

Answer :

A class that is derived from a particular class, perhaps with one or more classes in between. See also superclass, supertype.

Question 4 :

What is subtype ?

Answer :

If type X extends or implements type Y, then X is a subtype of Y. See also supertype.

Question 5 :

What is superclass ?

Answer :

A class from which a particular class is derived, perhaps with one or more classes in between. See also subclass, subtype.

Question 6 :

What is super ?

Answer :

A Java keyword used to access members of a class inherited by the class in which it appears.

Question 7 :

What is supertype ?

Answer :

The supertypes of a type are all the interfaces and classes that are extended or implemented by that type. See also subtype, superclass.

Question 8 :

What is switch ?

Answer :

A Java keyword used to evaluate a variable that can later be matched with a value specified by the case keyword in order to execute a group of statements.

Question 9 :

What is Swing ?

Answer :

A collection of graphical user interface (GUI) components that runs uniformly on any native platform which supports the Java virtual machine*. Because they are written entirely in the Java programming language, these components may provide functionality above and beyond that provided by native-platform equivalents. (Contrast with AWT.)

Question 10 :

What is synchronized ?

Answer :

A keyword in the Java programming language that, when applied to a method or code block, guarantees that at most one thread at a time executes that code.

Question 11 :

What is TCP/IP ?

Answer :

Transmission Control Protocol based on IP. This is an Internet protocol that provides for the reliable delivery of streams of data from one host to another.

Question 12 :

What is Technology Compatibility Kit (TCK) ?

Answer :

A test suite, a set of tools, and other requirements used to certify an implementation of a particular Sun technology conformant both to the applicable specifications and to Sun or Sun-designated reference implementations.

Question 13 :

What is thin client ?

Answer :

A system that runs a very light operating system with no local system administration and executes applications delivered over the network.

Question 14 :

What is 'this' ?

Answer :

A Java keyword 'that' can be used to represent an instance of the class in which it appears. 'this' can be used to access class variables and methods.

Question 15 :

What is thread ?

Answer :

The basic unit of program execution. A process can have several threads running concurrently, each performing a different job, such as waiting for events or performing a time-consuming job that the program doesn't need to complete before going on. When a thread has finished its job, the thread is suspended or destroyed. See also process.

Question 16 :

What is throw ?

Answer :

A Java keyword that allows the user to throw an exception or any class that implements the "throwable" interface.

Question 17 :

What is throws ?

Answer :

A Java keyword used in method declarations that specify which exceptions are not handled within the method but rather passed to the next higher level of the program.

Question 18 :

What is transaction ?

Answer :

An atomic unit of work that modifies data. A transaction encloses one or more program statements, all of which either complete or roll back. Transactions enable multiple users to access the same data concurrently.

Question 19 :

What is transaction isolation level ?

Answer :

The degree to which the intermediate state of the data being modified by a transaction is visible to other concurrent transactions and data being modified by other transactions is visible to it.

Question 20 :

What is transaction manager ?

Answer :

Provides the services and management functions required to support transaction demarcation, transactional resource management, synchronization, and transaction context propagation.

Question 21 :

What is transient ?

Answer :

A keyword in the Java programming language that indicates that a field is not part of the serialized form of an object. When an object is serialized, the values of its transient fields are not included in the serial representation, while the values of its non-transient fields are included.

Question 22 :

What is try ?

Answer :

A Java keyword that defines a block of statements that may throw a Java language exception. If an exception is thrown, an optional catch block can handle specific exceptions thrown within the try block. Also, an optional finally block will be executed regardless of whether an exception is thrown or not.

Question 23 :

What is type ?

Answer :

A class or interface.

Question 24 :

What is Unicode ?

Answer :

A 16-bit character set defined by ISO 10646. See also ASCII. All source code in the Java programming environment is written in Unicode.

Question 25 :

What is URI ?

Answer :

Uniform Resource Identifier. A compact string of characters for identifying an abstract or physical resource. A URI is either a URL or a URN. URLs and URNs are concrete entities that actually exist; A URI is an abstract superclass.

Question 26 :

What is URL ?

Answer :

Uniform Resource Locator. A standard for writing a text reference to an arbitrary piece of data in the WWW. A URL looks like "protocol://host/localinfo" where protocol specifies a protocol to use to fetch the object (like HTTP or FTP), host specifies the Internet name of the host on which to find it, and localinfo is a string (often a file name) passed to the protocol handler on the remote host.

Question 27 :

What is URN ?

Answer :

Uniform Resource Name. A unique identifier that identifies an entity, but doesn't tell where it is located. A system can use a URN to look up an entity locally before trying to find it on the Web. It also allows the Web location to change, while still allowing the entity to be found.

Question 28 :

What is variable ?

Answer :

An item of data named by an identifier. Each variable has a type, such as int or Object, and a scope. See also class variable, instance variable, local variable.

Question 29 :

What is virtual machine ?

Answer :

An abstract specification for a computing device that can be implemented in different ways, in software or hardware. You compile to the instruction set of a virtual machine much like you'd compile to the instruction set of a microprocessor. The Java virtual machine consists of a byte code instruction set, a set of registers, a stack, a garbage-collected heap, and an area for storing methods.

Question 30 :

What is void ?

Answer :

A Java keyword used in method declarations to specify that the method does not return any value. void can also be used as a nonfunctional statement.

Question 31 :

What is volatile ?

Answer :

A Java keyword used in variable declarations that specifies that the variable is modified asynchronously by concurrently running threads.

Question 32 :

What is Web server ?

Answer :

Software that provides services to access the Internet, an intranet, or an extranet. A Web server hosts Web sites, provides support for HTTP and other protocols, and executes server-side programs (such as CGI scripts or servlets) that perform certain functions.

Question 33 :

What is while ?

Answer :

A Java keyword used to declare a loop that iterates a block of statements. The loop's exit condition is specified as part of the while statement.

Question 34 :

What is world readable files ?

Answer :

Files on a file system that can be viewed (read) by any user. For example: files residing on Web servers can only be viewed by Internet users if their permissions have been set to world readable.

Question 35 :

What is wrapper ?

Answer :

An object that encapsulates and delegates to another object to alter its interface or behavior in some way.

Question 36 :

What is XML ?

Answer :

Extensible Markup Language. A markup language that allows you to define the tags (markup) needed to identify the data and text in XML documents.

Question 37 :

What is ACID ?

Answer :

The acronym for the four properties guaranteed by transactions: atomicity, consistency, isolation, and durability.

Question 38 :

What is Embedded Java Technology ?

Answer :

The availability of Java 2 Platform, Micro Edition technology under a restrictive license agreement that allows a licensee to leverage certain Java technologies to create and deploy a closed-box application that exposes no APIs.

Question 39 :

What is class method ?

Answer :

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.

Question 40 :

What is class variable ?

Answer :

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.

Question 41 :

What is constructor ?

Answer :

A pseudo-method that creates an object. In the Java programming language, constructors are instance methods with the same name as their class. Constructors are invoked using the new keyword.

Question 42 :

What is core packages ?

Answer :

The required set of APIs in a Java platform edition which must be supported in any and all compatible implementations.