3 Ways to Solve "No JVM installation found. Please install a 64-bit JDK" - Android Studio

You are an enthusiastic Java programmer who just learned about developing Android apps in Java. To start with you have installed Android Studio, which is the official Integrated Development Environment (IDE) for Android app development, based on IntelliJ IDEA, but as soon as you click on the Android Studio Desktop Icon to start Android Studio you are getting "No JVM installation found. Please install a 64-bit JDK" error? How do you solve this problem? Well, even though the error message is same, every problem is different depending upon your machine, the Java version, whether your desktop or laptop has 32-bit or 64-bit OS e.g. Windows 8.1 or Windows 10. Whether you have installed 32-bit Java or 64-bit JDK e.g. JDK 1.8.0 and what is the value of JAVA_HOME environment variable or whether you have defined it or not.

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How to Serialize Object in Java - Serialization Example

Serialization is one of the important but confusing concept in Java. Even experienced Java developer struggle to implement Serialization correctly. The Serialiation mechamism is provided by Java to save and restore state of an object programatically. Java provides two classes Serializable and Externalizable in java.io package to facilitate this process, both are marker interface i.e. an interface without any methods. Serializing an Object in Java means converting into a wire format so that you can either persists its state in a file locally or transfer it to another client via the network, hence it become an extrememly important concept in distributed applications running across several JVMs. There are other features in Java e.g. Remote Method Invocation (RMI) or HttpSession in Servlet API which mandates the participating object should impelment Serializable interface because they may be transffered and saved across the network.

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Iterative QuickSort Example in Java - without Recursion

The quicksort algorithm is one of the important sorting algorithms. Similar to merge sort, quicksort also uses divide-and-conquer hence it's easy to implement quicksort algorithm using recursion in Java, but it's slightly more difficult to write an iterative version of quicksort. That's why Interviewers are now asking to implement QuickSort without using recursion. The interview will start with something like writing a program to sort an array using quicksort algorithm in Java and most likely you will come up with a recursive implementation of quicksort as shown here. As a  follow-up, Interviewer will now ask you to code the same algorithm using Iteration.

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Top 5 JSON Library Java JEE Developers Should Know

The JSON format is one of the most popular formats to transfer and exchange data in web. Almost all RESTful web services take JSON input and provide JSON output but unfortunately JDK doesn't have built-in support for one of the most common web standard like JSON. As a Java developer if you want to develop RESTful web service and produce JSON data or if you are developing a client to an existing RESTFul web services and want to consume JSON response, you don't need to be disappointed. Fortunately, there are so many open source libraries and API available for creating, parsing and processing JSON response in Java e.g. Jackson, Google GSon, json-simple etc.

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How to get just DATE or TIME from GETDATE() in SQL Sever

The GETDATE is one of the most popular built-in methods of  Microsoft SQL Server, but unlike its name suggest, it doesn't return just date, instead it returns date with time information e.g. 2015-07-31 15:42:54.470 , quite similar to our own java.util.Date from Java world. If you want just date like 2015-07-31, or just time like 15:42:54.470 then you need to either CAST or CONVERT output of GETDATE function into DATE or TIME data type. From SQL Server 2008 onward, apart from DATETIME, which is used to store both date and time, You also have a DATE data type to store date without time e.g. 2015-07-31, and a TIME data type to store time without any date information e.g. 15:42:54.470. Since GETDATE() function return a DATETIME value, You have to use either CAST or CONVERT method to convert a DATETIME value to DATE or TIME in SQL Server.

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10 basic differences between Java and Groovy Programming

If you are working in Java, you might have heard about Scala, Groovy, and Closure. Out of these three Groovy seems to be gaining a place in Java projects more rapidly than others. Groovy is a Scripting language but runs on Java virtual machine. Every Java program can run on Groovy platform. As per official Groovy website, "Apache Groovy is a powerful, optionally typed and dynamic language, with static typing and static compilation capabilities, for the Java platform aimed at improving developer productivity thanks to a concise, familiar and easy to learn syntax". I think, they have highlighted the key capabilities of Groovy very well in that sentence. It basically further reduce the burden from Java developer with respect to coding. Now, you can put more focus on business logic and get your work done quickly without wasting time on writing more code.

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How to Remove CTRL-M characters From a File in UNIX and Linux

I wanted to transfer some files from Windows to Unix using FileZilla, but the problem arises when these files are transferred (Ascii or Binary mode both) and opened using VI we get ^M characters, also known as CTRL-M characters. I searched about this but the solutions were to remove these ^M characters when files are transferred using utilities. Is there any way that these ^M characters do not appear in the first place? Well, my search continues but I will share the solution which worked for me for removing control M characters i.e. CTRL-M or ^M characters. There are several UNIX commands e.g. dos2unix which can be used to convert a Windows or DOS generated files to UNIX one. You can also use sed command (stream editor) to remove CTRL-M characters without opening the file, very useful if you are removing CTRL-M characters from a large file. Alternatively, you can use VI command to open the file and replace ^M characters with nothing.

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