# Calculating Students’ Exam Grades in Java Assignment Help

The task required to implement two simple Java applications. The first application created by our Java assignment help experts calculates the age of a person on one of the planets from a given set of data. To calculate age, one had to use the given formula. The second application required implementation of student exam grades processing: the application must read the input file (containing data about students’ grades) in a specific format, perform necessary actions and calculations and output the result into another file.

• Computing a Person’s Age and Students’ Grades

## Computing a Person’s Age and Students’ Grades

```PlanetAge.java import java.util.HashMap; import java.util.Map; import java.util.Scanner; /* * Name: * Date: * Description: console application for calculating age on other planets */ public class PlanetAge { // initializing dictionary for storing length of planet year private static final Map planetD = new HashMap<>(); static { // populating dictionary with data for each planet planetD.put("Mercury", 88); planetD.put("Venus", 225); planetD.put("Jupiter", 4380); planetD.put("Saturn", 10767); } public static void main(String[] args) { // creating scanner to read from the console try (Scanner scanner = new Scanner(System.in)) { // asking user to enter the age System.out.print("Please, enter your Earth age: "); // reading user response int age = Integer.parseInt(scanner.nextLine().trim()); // iterating over planets (records in the dictionary) to output information for each planet for (Map.Entry pair : planetD.entrySet()) { // calculating age on the current planet int planetAge = (age * 365) / pair.getValue(); // outputting result System.out.println("Your age on " + pair.getKey() + " is " + planetAge); } } } } Exam.java import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.util.*; /* * Name: * Date: * Description: console application for calculating age on other planets */ public class Exam { public static void main(String[] args) { // a java collection to store read data List scores = new ArrayList<>(); // creating scanner to read from scores file try (Scanner scanner = new Scanner(new File("scores.txt"))) { // reading all lines in the file while (scanner.hasNextLine()) { // scanning and trimming new line String line = scanner.nextLine().trim(); // skip empty lines if (line.isEmpty()) { continue; } // splitting line with commas String[] parts = line.split(","); // creating student name from second and third part String name = parts[1].trim() + " " + parts[2].trim(); // parsing double score from a first comma-separated file double score = Double.parseDouble(parts[0].trim()); // calculating student's grade char grade; if (score >= 90) { grade = 'A'; } else if (score >= 80) { grade = 'B'; } else if (score >= 70) { grade = 'C'; } else if (score >= 60) { grade = 'D'; } else { grade = 'F'; } // adding read score to collection scores.add(new StudentScore(name, score, grade)); } } catch (IOException e) { // interrupt application in case file read error throw new RuntimeException(e); } // creating writer to write data to report file try (PrintWriter pw = new PrintWriter(new File("report.txt"))) { // variable for cumulating all-students total score double totalScore = 0.0; // array, storing several students for each grade int[] grades = new int[6]; // constructing output with a string builder StringBuilder builder = new StringBuilder(); // adding title builder.append(String.format("%55s", "Exam Results Report")).append(System.lineSeparator()); builder.append(System.lineSeparator()); // adding headers builder.append("Student Name Letter Grade Score").append(System.lineSeparator()); builder.append("=========================== ============ =====").append(System.lineSeparator()); // iterating over a collection of student data and output it for (StudentScore studentScore : scores) { builder.append(String.format("%-37s%c%20.1f",studentScore.name,studentScore.grade,studentScore.score)); builder.append(System.lineSeparator()); // adding current student score to total score totalScore += studentScore.score; // incrementing correspondent grade counter grades[studentScore.grade - 'A']++; } // outputting number of exams builder.append(System.lineSeparator()).append(System.lineSeparator()); builder.append("Total number of Exams: ").append(scores.size()).append(System.lineSeparator()); builder.append(System.lineSeparator()).append(System.lineSeparator()); // outputting grades counters for (int i = 0; i<6; i++) { if (i == 4) { continue; } builder.append("Total Number of ").append((char)('A'+i)).append("s: ").append(grades[i]).append(System.lineSeparator()); } // outputting average exam score builder.append(System.lineSeparator()).append(System.lineSeparator()); builder.append("Average Exam Score: ").append(String.format("%.2f", (totalScore/scores.size()))).append(System.lineSeparator()); pw.write(builder.toString()); } catch (IOException e) { // interrupt application in case file open error throw new RuntimeException(e); } } private static class StudentScore { final String name; final double score; final char grade; public StudentScore(String name, double score, char grade) { this.name = name; this.score = score; this.grade = grade; } } } ```
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