我开始研究我的第一个java项目，这是一个基本的RPG，我有一个关于法术的问题。我有一个名为Character的抽象类，它由一些子类扩展（如Fighter，Mage等）。只有施法者可以施放法术。关于法术 - 我有一个名为Spell的类，它描述了一个咒语（它的名字，它的效果，法术力等）。所有法术都存储在SpellsList类中，该类具有spellsList列表（类Spell的对象）。我有一个Effect类（非常合理，它将成为一个界面）有一些效果，如＆＃34; damage＆＃34;并且＆＃34;治愈＆＃34;但是我不能同时使用它，我只想测试我的工作。
我的问题是Mage的方法addToSpellBook和showSpellBook给出了编译错误：java can't find symbol: method addToSepllBook, location: variable hero of type Game.Character。也适用于showSpellBook。为什么以及如何解决它？
（问题可能出在Mage / Spell / SpellsList课程，而不是Character这个很长，所以它不那么令人生畏:)）
public class Game {
public static void main(String[] args) throws IOException {
CharacterCreator heroCreator = new CharacterCreator();
CharacterCreator.showAllClasses();
Scanner sc = new Scanner(System.in);
int scan = sc.nextInt();
String chosenClass = CharacterCreator.getCharacterClass(scan);
Character hero = CharacterCreator.createCharacter(chosenClass);
try {
hero.displayCharacter();
}catch (Exception e){
System.out.println("Wrong input");
}
if (hero.getCharacterClass().equals("Mage")){
hero.addToSpellBook("Fireball");
hero.showSpellBook();
}
}
}
public class CharacterCreator {
public static Character createCharacter(String chosenClass) {
Character hero = null;
System.out.println("Choose Name:");
Scanner nameIn = new Scanner(System.in);
String name = nameIn.next();
switch (chosenClass) {
case "Fighter":
return new Fighter(name);
case "Rogue":
return new Rogue(name);
case "Mage":
return new Mage(name);
case "Cleric":
return new Cleric(name);
case "def":
System.out.println("Wrong input");
return null;
default:
return null;
}
}
public static void showAllClasses(){
System.out.println("Choose a character: ");
System.out.println("1. Fighter");
System.out.println("2. Rogue");
System.out.println("3. Mage");
System.out.println("4. Cleric");
}
public static String getCharacterClass(int scan){
String classIn;
switch (scan) {
case 1:
classIn = "Fighter";
break;
case 2:
classIn = "Rogue";
break;
case 3:
classIn = "Mage";
break;
case 4:
classIn = "Cleric";
break;
default:
System.out.println("Enter again");
classIn = "def";
}
return classIn;
}
}
abstract public class Character {
private String name;
private String characterClass;
private int level;
private int hp;
private int currentHp;
private int armorClass;
private long xp;
/*private int BAB; /*Base attack bonus*/
private int strength;
private int constitution;
private int dexterity;
private int intelligence;
private int wisdom;
private int charisma;
protected Character(String name){
setName(name);
setCharacterClass("Class");
setLevel(1);
setStrength(10);
setConstitution(10);
setDexterity(10);
setIntelligence(10);
setWisdom(10);
setCharisma(10);
setHp(0);
setCurrentHp(getHp());
setArmorClass(10);
setXp(0);
}
void displayCharacter() throws IOException{
System.out.print("\n\n\n");
System.out.println("Name: " + getName());
System.out.println("Class: " + getCharacterClass());
System.out.println("Level: " + getLevel());
System.out.println("HP: " + getHp());
System.out.println("Current HP: " + getCurrentHp());
System.out.println("Armor Class: " + getArmorClass());
System.out.println("***************");
System.out.println("Attributes: ");
System.out.println("Strength: " + getStrength());
System.out.println("Constitution: " + getConstitution());
System.out.println("Dexterity: " + getDexterity());
System.out.println("Intelligence: " + getIntelligence());
System.out.println("Wisdom: " + getWisdom());
System.out.println("Charisma: " + getCharisma());
System.out.println("***************");
System.out.println("XP: " + getXp());
}
public int getModifier(int number){
int mod = (int)((number -10)/2);
return mod;
}
public String getName() { return name; }
public String getCharacterClass() { return characterClass; }
public int getLevel() { return level; }
public int getHp() { return hp; }
public int getCurrentHp() { return currentHp; }
public int getArmorClass() { return armorClass; }
public int getStrength(){ return strength; }
public int getConstitution(){ return constitution; }
public int getDexterity(){ return dexterity; }
public int getIntelligence(){ return intelligence; }
public int getWisdom(){ return wisdom; }
public int getCharisma(){ return charisma;}
public long getXp(){ return xp;}
protected void setName(String Name) { name = Name; }
protected void setCharacterClass(String characterClass) { this.characterClass = characterClass; }
protected void setLevel(int lvl){ level = lvl; }
protected void setHp(int hitPoints){ hp = hitPoints; }
protected void setCurrentHp(int curHp){ currentHp = curHp; }
protected void setArmorClass(int ac){ armorClass = ac; }
protected void setStrength(int str){ strength = str; }
protected void setConstitution(int con){ constitution = con; }
protected void setDexterity( int dex) { dexterity = dex; }
protected void setIntelligence(int intel){ intelligence = intel; }
protected void setWisdom(int wis){ wisdom = wis; }
protected void setCharisma(int cha){charisma = cha; }
protected void setXp(int XP){xp = XP; }
}
public class Mage extends Character {
private List<Spell> spellBook;
public Mage(String name){
super(name);
setName(name);
setCharacterClass("Mage");
setLevel(1);
setStrength(10);
setConstitution(10);
setDexterity(14);
setIntelligence(16);
setWisdom(14);
setCharisma(10);
setHp((int) (4 + getModifier(getConstitution())));
setCurrentHp(getHp());
setArmorClass(10 + getModifier(getDexterity()));
spellBook = null;
}
void addToSpellBook(String spellName){
Spell newSpell;
newSpell = SpellsList.getSpell(spellName);
spellBook.add(newSpell);
}
void showSpellBook(){
for (Iterator<Spell> iter = spellBook.iterator(); iter.hasNext(); ) {
Spell spell = iter.next();
if (spellBook.equals(spell.getSpellName())) {
System.out.println("Spell name: " + spell.getSpellName());
System.out.println("Spell effect: " + spell.getEffect());
}
}
}
}
public class Spell {
private String name;
private int spellLevel;
private String effect;
private int manaCost;
private int duration;
Spell(String name, int spellLevel, String effect, int manaCost, int duration){
this.name = name;
this.spellLevel = spellLevel;
this.effect = effect;
this.manaCost = manaCost;
this.duration= duration;
}
void castSpell(String spellName, Character hero, Character target){
try {
Spell spell = SpellsList.getSpell(spellName);
System.out.println("You casted: " + spellName);
System.out.println("Spell effect: " + spell.effect);
}
catch (Exception e){
System.out.println("No such spell");
}
}
String getSpellName(){ return name; }
int getSpellLevel() {return spellLevel; }
String getEffect(){ return effect; }
int getManaCost(){
return manaCost;
}
int getDuration() { return duration; }
}
public class SpellsList {
static List<Spell> spellsList = new ArrayList<Spell>();
static
{
spellsList.add(new Spell("Fireball", 3, "damage", 5,0 ));
spellsList.add(new Spell("Ice Storm", 4, "damage", 8, 0));
spellsList.add(new Spell("Heal", 2, "heal", 4, 0));
}
static Spell getSpell(String spellName) {
try {
for (Iterator<Spell> iter = spellsList.iterator(); iter.hasNext(); ) {
Spell spell = iter.next();
if (spellName.equals(spell.getSpellName())) {
return spell;
}
}
} catch (Exception e){
System.out.println(spellName + " haven't been found in spells-list");
return null;
}
return null;
}
}
答案 0 :(得分：1)
英雄是Character类型。你应该把它投给法师。或者在Character类中添加addToSpellBook并在Mage类中覆盖它。类似的东西：
if(hero instanceof Mage)
((Mage) hero).addToSpellBook();
答案 1 :(得分：0)
您在课程addToSpellBook上调用了代码showSpellBook和Character，但您的班级Character中没有包含此名称的方法。
答案 2 :(得分：0)
编译时的变量类型与执行期间的类有所不同。问题是你的英雄变量不是Mage类型，而是Character类型，只能访问任何Character可用的方法。
在尝试确保hero是Mage的实例时，编译器也没有注意到您的逻辑。要告诉它你知道你有Mage并希望使用你需要施放的Mage方法。
您的验证方式没问题，但我建议您使用instanceof关键字。
if(hero instanceof Mage) {
((Mage)hero).addToSpellBook("Fireball");
((Mage)hero).showSpellBook();
}