public void deleteRecord(DatabaseContainer db, MyScanner sc) {
int id =
sc.nextInt(
"Please enter the id of the sudent you wish to delete: ", 1000000000, 1999999999);
if (db.getFile().deleteStudent(db.getFile().getStudent(id)))
System.out.println("Delete successful!");
else System.out.println("That student appears to be gone already!");
}
public void showCount(DatabaseContainer db) {
try {
System.out.println(
"There are " + db.getFile().getRecordCount() + " total records in the database.");
} catch (IOException ex) {
System.out.println(
"IOException in MainApp::showCount -> StudentRandomFile::getRecordCount()");
}
}
public void showAll(DatabaseContainer db) {
ArrayList<Student> results = db.getFile().getStudents();
if (!results.isEmpty()) {
System.err.println("All the entries: ");
for (Student s : results) {
System.out.println("**********");
System.out.println(s);
}
} else System.out.println("No entries found!");
}
public void searchByRange(DatabaseContainer db, MyScanner sc) {
String typeStr =
sc.validate("Please enter which field you want to search (age / gpa): ", "age|gpa");
boolean type;
if (typeStr.equals("age")) type = db.getFile().AGE_TYPE;
else type = db.getFile().GPA_TYPE;
int lo = sc.nextInt("What is the lower range of your search?");
int hi = sc.nextInt("What is the higher ranger of your search?");
ArrayList<Student> results = db.getFile().searchByRange(hi, lo, type);
if (!results.isEmpty()) {
System.out.println("Results found: ");
for (Student s : results) {
System.out.println("**********");
System.out.println(s);
}
} else System.out.println("No results found!");
}
public void searchByRegex(DatabaseContainer db, MyScanner sc) {
String regex = sc.nextLine("Please enter the regex you want to search with: ", 1, 100);
ArrayList<Student> results = db.getFile().searchByRegex(regex);
if (!results.isEmpty()) {
System.out.println("Results found: ");
for (Student s : results) {
System.out.println("**********");
System.out.println(s);
}
} else System.out.println("No results found!");
}
public void addRecord(DatabaseContainer db, MyScanner sc) {
int id =
sc.nextInt("Please enter student ID (1000000000 - 1999999999): ", 1000000000, 1999999999);
String fName = sc.nextLine("Please enter student First Name: ", 1, 50);
String lName = sc.nextLine("Please enter student Last Name: ", 1, 50);
int age = sc.nextInt("Please enter student age: ");
boolean sex;
String sexStr = sc.validate("Please enter the student sex (male / female)", "male|female");
if (sexStr.equals("male")) sex = true;
else sex = false;
double GPA = sc.nextDouble("Please enter the student's current GPA (0-100): ", 0.0, 100.0);
Student newStudent = new Student(id, fName, lName, age, sex, GPA);
db.getFile().addStudent(newStudent);
System.out.println("Student added!");
}
public void editRecord(DatabaseContainer db, MyScanner sc) {
int id =
sc.nextInt("Please enter the id of the student you wish to edit: ", 1000000000, 1999999999);
Student s = db.getFile().getStudent(id);
int choice =
sc.nextInt(
"Please enter the number of the field you wish to edit:"
+ "\n1. ID"
+ "\n2. First Name"
+ "\n3. Last Name"
+ "\n4. Age"
+ "\n5. Sex"
+ "\n6. Current GPA",
1,
6);
if (choice == 1) {
s.setID(
sc.nextInt(
"Please enter student ID (1000000000 - 1999999999): ", 1000000000, 1999999999));
} else if (choice == 2) {
s.setFirstName(sc.nextLine("Please enter student First Name: ", 1, 50));
} else if (choice == 3) {
s.setLastName(sc.nextLine("Please enter student Last Name: ", 1, 50));
} else if (choice == 4) {
s.setAge(sc.nextInt("Please enter student age: "));
} else if (choice == 5) {
boolean sex;
String sexStr = sc.validate("Please enter the student sex (male / female)", "male|female");
if (sexStr.equals("male")) sex = true;
else sex = false;
s.setSex(sex);
} else if (choice == 6) {
s.setCurrentGPA(
sc.nextDouble("Please enter the student's current GPA (0-100): ", 0.0, 100.0));
}
System.out.println("Record Edited!");
}
public void deleteAll(DatabaseContainer db) {
if (db.getFile().deleteAll()) System.out.println("Delete successful!");
else System.out.println("Something seems to have gone wrong."); // IOException
}
public void run() {
DatabaseContainer db = new DatabaseContainer();
MyScanner sc = new MyScanner();
System.out.println(":::::::::::::::::::::::::::::::");
System.out.println("Welcome to the database system!");
int choice = 0;
while (choice != 4) {
printMainMenu();
choice = sc.nextInt("\nEnter your choice: ", 1, 4);
if (choice == 1) {
String fileName =
sc.nextLine("Enter a name for your new database file (eg. something.db)", 3, 50);
boolean valid = db.create(fileName);
while (!valid) {
fileName = sc.nextLine("That file already exists, please enter another", 3, 50);
valid = db.create(fileName);
}
System.out.println("Database created!");
} else if (choice == 2) {
if (!db.isEmpty()) {
System.out.println("Here is a list of existing files: ");
db.printFileNames();
String fileName = sc.nextLine("\nEnter the name of a valid database to open: ", 3, 50);
boolean valid = db.open(fileName);
while (!valid) {
fileName = sc.nextLine("That filename does not exist, please try another.", 3, 50);
valid = db.create(fileName);
}
useOpenMenu(db, sc);
} else {
System.out.println("There is currently no existing database files.");
}
} else if (choice == 3) {
if (!db.isEmpty()) {
System.out.println("Here is a list of existing files: ");
db.printFileNames();
String fileName = sc.nextLine("\nEnter the name of a valid database to delete: ", 3, 50);
boolean valid = db.delete(fileName);
while (!valid) {
fileName = sc.nextLine("That filename does not exist, please try another.", 3, 50);
valid = db.delete(fileName);
}
} else {
System.out.println("There is currently no existing database files.");
}
System.out.println("Database deleted!");
}
}
}