Technology Questions

The purpose of garbage collection is to identify and discard objects that are no longer needed by a program so that their resources can be reclaimed and reused. A Java object is subject to garbage collection when it becomes unreachable to the program in which it is used.

Java applications can call code written in C, C++, or assembler. This is sometimes done for performance and sometimes to access the underlying host operating system or GUI API using the JNI.

The steps for doing that are:

First write the Java code and compile it

Then create a C header file

Create C stubs file

Write the C code

Create shared code library (or DLL)

Run application

The ServiceInstaller class, also known as the project installer class, is used to install a Windows service.

The following are the usages of the Command object in AD0.NET:

The Command object in AD0.NET executes a command against the database and retrieves a DataReader or DataSet object.

  =>  It also executes the INSERT, UPDATE, or DELETE command against the database.
  =>  All the command objects are derived from the DbCommand class.
  =>  The command object is represented by two classes: SqlCommand and OleDbCommand.
  =>  The Command object provides three methods to execute commands on the database:
  =>  The ExecuteNonQuery() method executes the commands and does not return any value.
  =>  The ExecuteScalar() method returns a single value from a database query.
  =>  The ExecuteReader() method returns a result set by using the DataReader object.

Node.js is a framework for web applications built on Google Chrome's JavaScript Engine(V8 Engine).

Node.js is comes with runtime environment on which a cript based on javascript can be interpreted and executed (It is analogus to JVM to JAVA byte code). This runtime environment allows to execute a JavaScript code on any machine outside a browser. Because of this runtime of Node.js, JavaScript is now can be executed on server also.

Node.js is provides a rich library of various javascript modules which eases the developement of web application using Node.js to greater extents.

Amazon SQS is a message passing mechanism that is used for communication between different connectors that are connected with each other. It also acts as a communicator between various components of Amazon. It keeps all the different functional components together. This functionality helps different components to be loosely coupled, and provide an architecture that is more failure resilient system.

-The shift() method is similar as the pop() method but the difference is that Shift method works at the beginning of the array. 

-The shift() method take the first element off of the given array and returns it. The array on which is called is then altered.

For example

var myarray = ["apple ", "banana ", "mango "]; 

console.log(myarray.shift());

console.log(myarray);

we get the following console output:

apple

["banana ", "mango "];

When we call shift() on an empty array, it will return an undefined value.