It as a starting point and to add instructions to print all of the Once you understand how this program works, your task is to use The program file includes documentation in the form ofĬomments, so study this program and let me know if you have any Information to the screen (using standard error), andĮxit. Program will throw an exception, print the exception Try block if any unrecoverable errors areĮncountered along the way (such as a missing input file), the That all of these operations take place inside a When the main input loop is finished, the list should containĮxactly 500 maps, one for each record in the database. Structure, a list of maps, makes it easy to retrieve anyĭesired field for any of the names in theĪrrayList, while preserving their original orderįinally, it prints the number of records that were read, and These pairs then become the key/value pairs in a newĮach row's HashMap is added to another ArrayList, which acts as a "container" forĪll the names in the file. It then pairs theseįields with the corresponding field names from the header row It then reads the remaining rows, splitting the fields in each (using the comma as the delimiter) into an It reads the header row and splits the field names The attached Java program is provided for you as a demonstration The first row of theįile, called the header row, contains descriptive labels The fields are joined with commas, which act asĭelimiters for the fields. Individual attributes of the person (first name, last (also known as fields) within each row correspond to Particular file, the "rows" (also known as records)Ĭorrespond to information about a single person, and the "columns" Files in this format are often used to store The attached input file is a "database" of names and addressesįormat. Sample code for maps and lists given in the "Java Fundamentals, Before proceeding with this lab, you should try the In working with maps and lists in Java, as well as file input and This assignment is intended to give you some additional practice That we assigned to them when we added them to the collection). To the elements of a map by their keys (the names (its location within the collection), as we do with lists, we refer Of referring to an element according to its numeric index Unlike lists, the elements within the collection are Recall that maps are collections of values, but We have recently been discussing Java collection classes, such
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