In this assignment, you will develop a tool which implements the key-sorting approach to create an index for a given data-file, and use them in an example application to show a search operation in action.
In JSON file, dataFileName and indexFileName are the names of data file name and index file name, including full path, respectively. The datafile contains any type of records where records come in no particular order. By the way, datafile must be exist and given at the beginning. Value of recordLength shows the length of data file records in bytes. Normally, index file is not exist initially and your tool will create it when corresponding method is invoked. Index file includes only key and relative record numbers pointing to record in datafile, as in key-sorting approach of simple indexing. Index file is sorted in the order of order field value, where ASC and DESC are ascending and descending, relatively. Value of keyEncoding shows how key field is to be interpreted: CHR for one byte long text, BIN for binary, UTF for multi-byte character representation. To test your application, a sample datafile shown below will be provided to you. rowID(BIN,4) studentID(CHR,10) firstName(UTF,20), lastName(UTF,20), phone(CHR,10)
Please pay attention that, your application will be tested with another datafile and/or setting file, when grading. It means that your tool needs to be generic working with different settings with different datafile. Functionality Your tool must implement minimum of the following commands: ● open command This command takes a parameter that is the name of the json file. It opens the json file and reads the given settings. Then, it reads the whole index file in to memory and waits for the further commands. ● create_index command This command creates the index file using key field which is specified in the json file. You need to implement the simple indexing method and you should use the relative record number or absolute byte address as pointer. You can use any sorting algorithm you wish. ● search command This command finds the record for the given key in index file using binary search and fetches corresponding record from datafile. ● close command This command closes the used files and frees the memory.