implement requiring every configured character type in password generator

src/main/java/PasswordGenerator.java

@@ -12,6 +12,7 @@ public class PasswordGenerator {
     private boolean useLowercase = true;
     private boolean useDigits = true;
     private boolean useSpecialCharacters = true;
+    private boolean requireEveryConfiguredCharacterType = true;
 
 
     public String generateRandomPassword() {
@@ -33,7 +34,23 @@ public class PasswordGenerator {
         }
 
         for (int generatorPosition = 0; generatorPosition < getLength(); generatorPosition++) {
-            generatedPassword.append(characterPool.charAt(rand.nextInt(characterPool.length())));
+            String customCharacterPool = characterPool;
+
+            if (isRequireEveryConfiguredCharacterType()) {
+                if (generatorPosition == 0 && isUseLowercase()) {
+                    customCharacterPool += lowercaseCharacters;
+                } else if (generatorPosition == 1 && isUseUppercase()) {
+                    customCharacterPool += uppercaseCharacters;
+                } else if (generatorPosition == 2 && isUseDigits()) {
+                    customCharacterPool += digits;
+                } else if (generatorPosition == 3 && isUseSpecialCharacters()) {
+                    customCharacterPool += specialCharacters;
+                } else {
+                    customCharacterPool = characterPool;
+                }
+            }
+
+            generatedPassword.append(customCharacterPool.charAt(rand.nextInt(customCharacterPool.length())));
         }
         return generatedPassword.toString();
     }
@@ -70,6 +87,14 @@ public class PasswordGenerator {
         this.useSpecialCharacters = useSpecialCharacters;
     }
 
+    public boolean isRequireEveryConfiguredCharacterType() {
+        return requireEveryConfiguredCharacterType;
+    }
+
+    public void setRequireEveryConfiguredCharacterType(boolean requireEveryConfiguredCharacterType) {
+        this.requireEveryConfiguredCharacterType = requireEveryConfiguredCharacterType;
+    }
+
     public int getLength() {
         return length;
     }

src/test/java/PasswordGeneratorTest.java

@@ -55,4 +55,11 @@ class PasswordGeneratorTest {
         passwordGenerator.setUseSpecialCharacters(true);
         assertTrue(Pattern.compile("^(?=.*[.!?=@#$()%^&/*_\\-+]).+$").matcher(passwordGenerator.generateRandomPassword()).matches());
     }
+
+    @Test
+    void testPasswordForEveryRequiredCharacter() {
+        passwordGenerator.setRequireEveryConfiguredCharacterType(true);
+        PasswordValidator passwordValidator = new PasswordValidator();
+        assertTrue(passwordValidator.validate(passwordGenerator.generateRandomPassword()));
+    }
 }