Technology Questions

Java Collections Framework provides a well designed set of interfaces and classes that support operations on a collections of objects. The most basic interfaces that reside in the Java Collections Framework are:

Collection, which represents a group of objects known as its elements.

Set, which is a collection that cannot contain duplicate elements.

List, which is an ordered collection and can contain duplicate elements.

Map, which is an object that maps keys to values and cannot contain duplicate keys.

JavaScript is a scripting language most often used for client-side web development.

Executing two or more blocks (threads) of a program at a time is called MultiThreading.

The foreground activity, being the most important among the other states, is only killed or terminated as a last resort, especially if it is already consuming too much memory. When a memory paging state has been reach by a foreground activity, then it is killed so that the user interface can retain its responsiveness to the user.

The mapreduce framework contains most of the key architecture principles of cloud computing such as:

- Scale: The framework is able to expand itself in direct proportion to the number of machines available.

- Reliable: The framework is able to compensate for a lost node and restart the task on a different node.

- Affordable: A user can start small and over time can add more hardware.

Syntax:

SORT   file-1 ON ASCENDING/DESCENDING KEY key....

USING  file-2

GIVING file-3.

USING can be substituted by INPUT PROCEDURE IS para-1 THRU para-2

GIVING can be substituted by OUTPUT PROCEDURE IS para-1 THRU para-2.

file-1 is the sort workfile and must be described using SD entry in FILE SECTION.

file-2 is the input file for the SORT and must be described using an FD entry in FILE SECTION and SELECT clause in FILE CONTROL.

file-3 is the outfile from the SORT and must be described using an FD entry in FILE SECTION and SELECT clause in FILE CONTROL.

file-1, file-2 & file-3 should not be opened explicitly.

INPUT PROCEDURE is executed before the sort and records must be RELEASEd to the sort work file from the input procedure.

OUTPUT PROCEDURE is executed after all records have been sorted. Records from the sort work file must be RETURNed one at a time to the output procedure.

String Args (String []) is an array of parameters of type String.

In Java, 'args' contains the supplied command-line arguments as an array of String objects. In other words, if you run your program as 'java MyProgram Hello World' then 'args' will contain ["Hello", "World"]. When a java class is executed from the console, the main method is what is called.