Start Apache Solr instance using " solr start " from bin directory of Apache Solr home directory. Or see first article how to setup Apache Solr and start it first time . Create New Core  Before we index sample data, we must create a core.  Core is like a table that contain many records and has a unique configuration. Each record in Solr is called a document . So we create core and add documents to it which are indexed by the Solr, so that we could search. One Solr instance may have more than one cores, each with different set of documents and unique configurations. So we need to create a core, before we add documents into it. Here is how we create a core: 1. In CLI, go to bin directory e.g. D:\solr-6.4.2/bin> and issue following command: solr create -c core1 -d basic_configs -c specifies the core name -d specifies the folder that contains core configuration data. Solr instance already have a folder named basic_configs which contains default configuration inf...

Introduction to Apache Solr Apache Solr is a search server built as a web-application using Java language. Its not directly used by end-users to perform search operations on organizational data but by software developers (called Search Engineers) to integrate their softwares or applications with Apache Solr to use Solr search features. That means, Solr interface (way to interact with Solr) is not built for humans but for programs. Developers first submit their data to Solr using Solr RESTful API, the data is indexed by Solr. Once the data is indexed, developers send search queries with different filters (to refine search) to Solr server using Solr APIs. Solr returns the results in JSON or XML fromat that is parsed and displayed to end-users. Apache Solr Admin Interface Apache Solr provide Admin Interface but its target users are not end-users because it requires technical knowledge to use. Admin Interface is used by Search Engineers to test search queries, modify schemas and...

Updated On: Oct. 31, 2020 6.1: Make an array of n elements and initialize it from user input. Get n from user. Print all the numbers, find and print the minimum number and its index in the array, find maximum number and its index in the array, find the average of all numbers. 6.2: Roll a 6 faces dice 1 million times, print how many times each face appear along with its percentage? Use arrays to store each face count e.g. face[3] shall store how many times 4 appeared during random rolls. See figure 7.7 of book for detail (Java How to Program, By Dietel. 10th Edition). 6.3: Make a program that shuffle cards. Print the deck before shuffling and after shuffling. See Figure 7.9, 7.10 and 7.11 from reference book. 6.4. Update  Task 5 such that PhoneNumber shall be an instance attribute of Student. To let user store multiple phone numbers, define phoneNumbers attribute of type PhoneNumber[]. Encapsulate phoneNumbers field. When creating a Student object, let user enter how many numbe...

Enum contants detail is explained in this video. First I discuss basic concepts required to understand Enum constants e.g. public access modifier, what are static and final fields. When we can make private constructor and can we define field of same class type in which it is declared. After these basics, I explained enum constants are just public static final fields of same class/enum type. Whenever we refer to these constants, we refer to same distinct objects stored in main memory. When we assign these references to others, JVM make copy of their reference only, it do not create new objects. Constructor of enum is private, so we can't create new objects of enum type from other classes.