String literals and String Objects String s1 = "abc"; String s2 = "abc"; Both string s1 and s2 refer to the same string object and value residing in the string literal pool. String A = new String("abc"); String B = new String("abc"); The two strings A & B are two different string objects, because we … Continue reading Java Strings
Category: Java
Java Static Initialization vs. Instance Initialization – When to use which?
Static Initialization Typically static initialization block is used to initialize static variables of a class. The block is called at the time of class initialization. It is called only once. You can initialize static variables inline. If more complicated logic is required for initialization, a static initialization block can be used. The static initialization blocks … Continue reading Java Static Initialization vs. Instance Initialization – When to use which?
Accessing Solr Cloud on AWS from SolrJ
We have a Solr cloud installation on AWS EC2 instances. We use the SolrJ Client from our Java application. Till date we used to have a Solr Cloud installation on our local machine in order to test the code against. As the team started growing, we realized that we should have a way to access … Continue reading Accessing Solr Cloud on AWS from SolrJ
Interfaces in Java8
Interfaces are a key feature of object oriented programming. An interface provides a set of methods that an implementing class must provide. One can assign instances of the class to variables of the interface type. As of Java8, an interface can contain default methods that an implementing class can inherit or override. Default methods (also … Continue reading Interfaces in Java8
Immutability in Java – What it takes to build an immutable class
Immutability means something that cannot be changed. In java an immutable class is one whose state cannot be changed once it has been created. This post aims to give a guideline on how to make a class immutable. The post contains an example of creating an immutable class.The complete code is available on Github The … Continue reading Immutability in Java – What it takes to build an immutable class
Getting Started with TestNG
TestNG is a testing framework which, inspired by JUnit and NUnit, but introduces things like dependency testing, grouping concept to make testing more powerful and easier to do. It is designed to cover all categories of tests: unit, functional, end-to-end, integration, etc...The NG in TestNG stands for Next Generation. TestNG requires JDK7 or higher.Reference: http://testng.org/doc/index.html … Continue reading Getting Started with TestNG
An Introduction to Zookeeper – Part I of the Zookeeper series
A distributed system consists of multiple computers that communicate through a computer network and interact with each other to achieve a common goal.Major benefits that distributed systems offer over centralized systems is scalability and redundancy. Systems can be easily expanded by adding more machines as needed, and even if one of the machines is unavailable, … Continue reading An Introduction to Zookeeper – Part I of the Zookeeper series
Multiple Java Installations on OSX and switching between them
Sometimes it may be necessary to have two versions of java on your OSX, and to switch between the two in a fast, reliable and convenient manner. This post aims to show how this can be achieved. I am currently using version 10.9.4 of OSX, and I was required to have both JAVA6 and JAVA7 … Continue reading Multiple Java Installations on OSX and switching between them
Java Inheritance – Super keyword
Inheritance is an important principle in object oriented programming. It is a mechanism in which one object acquires the property of another. The object which gives the properties is called as super/base/parent class and the one that receives the property is called as the sub/derived/child class. The child class inherits all fields and methods of … Continue reading Java Inheritance – Super keyword
Configuration and Coordination with Zookeeper
It took me a while to understand the concept of Zookeeper and it took me another some to understand how to use it for the task that I had begun with. This post is intended to help others cross the bridge faster.Dynamic Configuration Management for today's system comes with all the nitty-gritties that are involved … Continue reading Configuration and Coordination with Zookeeper
Anjana Shankar 