Merge branch 'master' into fix-pr-22

Author: phrdang

.github/workflows/java.yml .github/java.yml

@@ -1,4 +1,4 @@
-package com.codefortomorrow.advanced.chapter13.practice;
+package com.codefortomorrow.advanced.chapter13.solutions;
 
 /*
 Implement the iterative code as a recursive

src/com/codefortomorrow/advanced/chapter13/solutions/NegativeSum.java

@@ -0,0 +1,62 @@
+package com.codefortomorrow.advanced.chapter14.practice;
+
+/*
+Create the following classes that simply extend the `Exception` class: 
+
+- `InvalidUsernameException`
+- `InvalidPasswordException`
+- `InvalidAgeException`
+- `PasswordMismatchException`
+
+In the `Account` class, code a method called `createAccount` that takes a `username`, `age`,
+`password`, and `confirmPassword` as parameters. 
+
+In `createAccount`, throw an:
+
+- `InvalidUsernameException` - if the given username is <4 or >10 characters.
+- `InvalidPasswordException` - if the given password is <4 or >10 characters.
+- `InvalidAgeException` - if the given age is <18.
+- `PasswordMismatchException` - if the given password does not match the given confirm password.
+
+In your `main` method (within the `Account` class):
+
+- To simulate the creation of an account online, prompt the user to enter their username, age,
+  password, and their password again (to confirm).
+- Call the `createAccount` method continuously with the user's input and use `try`/`catch` to
+  handle the possible exceptions and print the appropriate error message. (You can assume that
+  the user input will only throw at most 1 exception.)
+- Keep asking the user for input until the account is created successfully.
+
+Example output:
+
+```
+Welcome to Account Creation!
+Enter username (4 to 10 characters): hi
+Enter age: 18
+Enter password (4 to 10 characters): thisislong
+Confirm password (4 to 10 characters): thisislong
+Invalid username.
+Enter username (4 to 10 characters): four
+Enter age: 18
+Enter password (4 to 10 characters): thisislong
+Confirm password (4 to 10 characters): thisislong
+Account created successfully!
+```
+*/
+
+public class Account {
+
+    public static void main(String[] args) {
+        // Write your code here
+    }
+
+    public static void createAccount(
+        String username,
+        int age,
+        String password,
+        String confirmPassword
+    ) {
+        // Write your code here
+    }
+}
+// Write exception classes here

src/com/codefortomorrow/advanced/chapter14/practice/Account.java

@@ -1,7 +1,5 @@
 package com.codefortomorrow.advanced.chapter14.practice;
 
-import java.io.*;
-
 /*
 The file “numbers.txt” has 100 random numbers
 (one on each line). Use file i/o to find the

src/com/codefortomorrow/advanced/chapter14/practice/Average.java

@@ -1,7 +1,5 @@
 package com.codefortomorrow.advanced.chapter14.practice;
 
-import java.io.*;
-
 /*
 Practice: Use File I/O to compare two files lexicographically.
 Lexicographical order is very similar to alphabetical order,

src/com/codefortomorrow/advanced/chapter14/practice/Lexico.java

@@ -0,0 +1,108 @@
+package com.codefortomorrow.advanced.chapter14.solutions;
+
+import java.util.Scanner;
+
+/*
+Create the following classes that simply extend the `Exception` class:
+
+- `InvalidUsernameException`
+- `InvalidPasswordException`
+- `InvalidAgeException`
+- `PasswordMismatchException`
+
+In the `Account` class, code a method called `createAccount` that takes a `username`, `age`,
+`password`, and `confirmPassword` as parameters.
+
+In `createAccount`, throw an:
+
+- `InvalidUsernameException` - if the given username is <4 or >10 characters.
+- `InvalidPasswordException` - if the given password is <4 or >10 characters.
+- `InvalidAgeException` - if the given age is <18.
+- `PasswordMismatchException` - if the given password does not match the given confirm password.
+
+In your `main` method (within the `Account` class):
+
+- To simulate the creation of an account online, prompt the user to enter their username, age,
+  password, and their password again (to confirm).
+- Call the `createAccount` method continuously with the user's input and use `try`/`catch` to
+  handle the possible exceptions and print the appropriate error message. (You can assume that
+  the user input will only throw at most 1 exception.)
+- Keep asking the user for input until the account is created successfully.
+
+Example output:
+
+```
+Welcome to Account Creation!
+Enter username (4 to 10 characters): hi
+Enter age: 18
+Enter password (4 to 10 characters): thisislong
+Confirm password (4 to 10 characters): thisislong
+Invalid username.
+Enter username (4 to 10 characters): four
+Enter age: 18
+Enter password (4 to 10 characters): thisislong
+Confirm password (4 to 10 characters): thisislong
+Account created successfully!
+```
+*/
+
+public class Account {
+
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+
+        System.out.println("Welcome to Account Creation!");
+        while (true) {
+            System.out.print("Enter username (4 to 10 characters): ");
+            String username = sc.next();
+            System.out.print("Enter age: ");
+            int age = sc.nextInt();
+            System.out.print("Enter password (4 to 10 characters): ");
+            String password = sc.next();
+            System.out.print("Confirm password (4 to 10 characters): ");
+            String confirmPassword = sc.next();
+
+            try {
+                createAccount(username, age, password, confirmPassword);
+                System.out.println("Account created successfully!");
+                sc.close();
+                break;
+            } catch (InvalidUsernameException e) {
+                System.out.println("Invalid username.");
+            } catch (InvalidPasswordException e) {
+                System.out.println("Invalid password.");
+            } catch (InvalidAgeException e) {
+                System.out.println("Must be 18 or older to create an account.");
+            } catch (PasswordMismatchException e) {
+                System.out.println("Passwords don't match!");
+            }
+        }
+    }
+
+    public static void createAccount(String username, int age, String password, String confirmPassword)
+        throws InvalidAgeException, InvalidPasswordException, InvalidUsernameException, PasswordMismatchException {
+            if (username.length() < 4 || username.length() > 10) {
+                throw new InvalidUsernameException();
+            }
+
+            if (age < 18) {
+                throw new InvalidAgeException();
+            }
+
+            if (password.length() < 4 || password.length() > 10) {
+                throw new InvalidPasswordException();
+            }
+
+            if (!password.equals(confirmPassword)) {
+                throw new PasswordMismatchException();
+            }
+      }
+}
+
+class InvalidUsernameException extends Exception {}
+
+class InvalidPasswordException extends Exception {}
+
+class InvalidAgeException extends Exception {}
+
+class PasswordMismatchException extends Exception {}

src/com/codefortomorrow/advanced/chapter14/practice/account/InvalidAgeException.java

@@ -34,43 +34,44 @@ public static void main(String[] args) {
 
         account1.deposit(200);
         withdraw(account1, 300);
-        System.out.println("Account 1: " + account1.getBalance());
+        System.out.printf("Account 1 Balance: $%.2f\n", account1.getBalance());
 
         account2.deposit(200);
         withdraw(account2, 1500);
-        System.out.println("Account 2: " + account2.getBalance());
+        System.out.printf("Account 2 Balance: $%.2f\n", account2.getBalance());
     }
 
-    public static void withdraw(BankAccount account, int amount) {
+    public static void withdraw(BankAccount account, double amount) {
         try {
             account.withdraw(amount);
         } catch (NotEnoughMoneyException e) {
-            int diff = Math.abs(amount - account.getBalance());
-            System.out.println(e.toString());
+            System.out.println(e.getMessage());
         }
     }
 }
 
 class BankAccount {
 
-    private int balance;
+    private double balance;
 
-    public BankAccount(int balance) {
+    public BankAccount(double balance) {
         this.balance = balance;
     }
 
-    public void deposit(int amount) {
-        balance += amount;
+    public void deposit(double amount) {
+        if (amount > 0) {
+            balance += amount;
+        }
     }
 
-    public void withdraw(int amount) throws NotEnoughMoneyException {
-        if (amount > balance) throw new NotEnoughMoneyException(
-            "Bank balance is short $" + Math.abs(balance - amount)
-        );
+    public void withdraw(double amount) throws NotEnoughMoneyException {
+        if (amount > balance) {
+            throw new NotEnoughMoneyException(String.format("Bank balance is short $%.2f", Math.abs(balance - amount)));
+        }
         balance -= amount;
     }
 
-    public int getBalance() {
+    public double getBalance() {
         return balance;
     }
 }

src/com/codefortomorrow/advanced/chapter14/practice/account/InvalidPasswordException.java

@@ -1,6 +1,7 @@
 package com.codefortomorrow.advanced.chapter16.solutions;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.LinkedList;
 
 /*
 Using the methods outlined in the “Benefits of LinkedLists” section,
@@ -15,6 +16,7 @@
 
 public class Access {
 
+    @SuppressWarnings("unused")
     public static void main(String[] args) {
         long a, b;