HashMap Explaination

How HashMap works in Java? With Animation!! whats new in java8 tutorial

How does java hashmap work ? HashMap is one of the most popular java.util data structures. Its one of the associative array implementations, here I have explained its internals in simple terms using an animation. Java8 adds a bit of enhancement to HashMap by using a balanced tree when there is too much has collisions.

Unable to open kernel device "\\.\Global\vmx86": The system cannot find the file

Unable to open kernel device

"
.\Global\vmx86": The system cannot find the file specified. Did you reboot

after installing VMware Workstation?

Failed to initialize

Solution for this type error which occurred when opening an vmplayer. 

try to re-install the vmx86 driver

open a cmd in adminmode and navigate to the VMware installation directory and run

 vnetlib -- uninstall vmx86 

reboot

check again with the net start command - this time it should say "service name  is invalid"

then run

 vnetlib -- install vmx86 

and reboot again

now it hopefully works

Second simple solutions is 

start CMD as administrator then run  "net start vmx86".

HotSpot or JRockit to find which JVM is running from JAVA

f you want to know whether the currently running JVM is HotSpot or JRockit, check System.getProperty("java.vm.name"). For me, it gives Java HotSpot(TM) 64-Bit Server VM on HotSpot and Oracle JRockit(R) on JRockit, although different versions/platforms may give slightly different results, so the most reliable method may be:

String jvmName = System.getProperty("java.vm.name");
boolean isHotSpot = jvmName.toUpperCase().indexOf("HOTSPOT") != -1;
boolean isJRockit = jvmName.toUpperCase().indexOf("JROCKIT") != -1;

Thorbjørn's suggestion to use java.vendor has the problem that the same vendor may produce multiple JVMs; indeed, since Oracle's acquisitions of BEA and Sun, both HotSpot and JRockit now report the same value: Oracle Corporation

If you want to find all JVMs installed on a system: the problem with Nambari's answer, to use the command java -version, is that the JVM can be installed on a machine yet not be present in the path. For Windows, scanning the registry could be a better approach.

New JAVA quiz real time score to email

Create a project in Eclipse

Download Eclipse Luna Here (Select Here Windows 32 Bit or 64 Bit based on your requirement) 

  - If the downloaded file is a zip file extract it C:\ folder  or to your desktop . Open the extracted folder click on eclipse.exe file . Thats it. Now you are all set. 

Create a project : 

 This steps will show you how to create a Java application project in Eclipse.

1. Choose File → New → Java Project from the Eclipse menu bar
2. Enter the Project name as  "com.[company or Institute name].[Module or project name] " , then click next and next 
3. Finish

Now you are able to see the project on the left side of the IDE , tree down the project  you are able to see the src folder and JRE system library folder . 

In the src folder create  15 folders (right click on the src folder New-> folder) name them from Lab1_[Date] to Lab15_[Date]