package com.iluwatar.stepbuilder; import java.util.ArrayList; import java.util.List; /** * The Step Builder class. */ public class CharacterStepBuilder { private CharacterStepBuilder() { } public static NameStep newBuilder() { return new CharacterSteps(); } /** * First Builder Step in charge of the Character name. * Next Step available : ClassStep */ public interface NameStep { ClassStep name(String name); } /** * This step is in charge of setting the Character class (fighter or wizard). * Fighter choice : Next Step available : WeaponStep * Wizard choice : Next Step available : SpellStep */ public interface ClassStep { WeaponStep fighterClass(String fighterClass); SpellStep wizardClass(String wizardClass); } /** * This step is in charge of the weapon. * Weapon choice : Next Step available : AbilityStep * No weapon choice : Next Step available : BuildStep */ public interface WeaponStep { AbilityStep withWeapon(String weapon); BuildStep noWeapon(); } /** * This step is in charge of the spell. * Spell choice : Next Step available : AbilityStep * No spell choice : Next Step available : BuildStep */ public interface SpellStep { AbilityStep withSpell(String spell); BuildStep noSpell(); } /** * This step is in charge of abilities. * Next Step available : BuildStep */ public interface AbilityStep { AbilityStep withAbility(String ability); BuildStep noMoreAbilities(); BuildStep noAbilities(); } /** * This is the final step in charge of building the Character Object. * Validation should be here. */ public interface BuildStep { Character build(); } /** * Step Builder implementation. */ private static class CharacterSteps implements NameStep, ClassStep, WeaponStep, SpellStep, AbilityStep, BuildStep { private String name; private String fighterClass; private String wizardClass; private String weapon; private String spell; private List abilities = new ArrayList<>(); @Override public ClassStep name(String name) { this.name = name; return this; } @Override public WeaponStep fighterClass(String fighterClass) { this.fighterClass = fighterClass; return this; } @Override public SpellStep wizardClass(String wizardClass) { this.wizardClass = wizardClass; return this; } @Override public AbilityStep withWeapon(String weapon) { this.weapon = weapon; return this; } @Override public BuildStep noWeapon() { return this; } @Override public AbilityStep withSpell(String spell) { this.spell = spell; return this; } @Override public BuildStep noSpell() { return this; } @Override public AbilityStep withAbility(String ability) { this.abilities.add(ability); return this; } @Override public BuildStep noMoreAbilities() { return this; } @Override public BuildStep noAbilities() { return this; } @Override public Character build() { Character character = new Character(name); if (fighterClass != null) { character.setFighterClass(fighterClass); } else { character.setWizardClass(wizardClass); } if (weapon != null) { character.setWeapon(weapon); } else { character.setSpell(spell); } if (!abilities.isEmpty()) { character.setAbilities(abilities); } return character; } } }