【设计模式】JAVA Design Patterns——Bridge（桥接模式）

public interface Weapon {
  void wield();
  void swing();
  void unwield();
  Enchantment getEnchantment();
}
 
public class Sword implements Weapon {
 
  private final Enchantment enchantment;
 
  public Sword(Enchantment enchantment) {
    this.enchantment = enchantment;
  }
 
  @Override
  public void wield() {
    LOGGER.info("The sword is wielded.");
    enchantment.onActivate();
  }
 
  @Override
  public void swing() {
    LOGGER.info("The sword is swinged.");
    enchantment.apply();
  }
 
  @Override
  public void unwield() {
    LOGGER.info("The sword is unwielded.");
    enchantment.onDeactivate();
  }
 
  @Override
  public Enchantment getEnchantment() {
    return enchantment;
  }
}
 
public class Hammer implements Weapon {
 
  private final Enchantment enchantment;
 
  public Hammer(Enchantment enchantment) {
    this.enchantment = enchantment;
  }
 
  @Override
  public void wield() {
    LOGGER.info("The hammer is wielded.");
    enchantment.onActivate();
  }
 
  @Override
  public void swing() {
    LOGGER.info("The hammer is swinged.");
    enchantment.apply();
  }
 
  @Override
  public void unwield() {
    LOGGER.info("The hammer is unwielded.");
    enchantment.onDeactivate();
  }
 
  @Override
  public Enchantment getEnchantment() {
    return enchantment;
  }
}

public interface Enchantment {
  void onActivate();
  void apply();
  void onDeactivate();
}
 
public class FlyingEnchantment implements Enchantment {
 
  @Override
  public void onActivate() {
    LOGGER.info("The item begins to glow faintly.");
  }
 
  @Override
  public void apply() {
    LOGGER.info("The item flies and strikes the enemies finally returning to owner's hand.");
  }
 
  @Override
  public void onDeactivate() {
    LOGGER.info("The item's glow fades.");
  }
}
 
public class SoulEatingEnchantment implements Enchantment {
 
  @Override
  public void onActivate() {
    LOGGER.info("The item spreads bloodlust.");
  }
 
  @Override
  public void apply() {
    LOGGER.info("The item eats the soul of enemies.");
  }
 
  @Override
  public void onDeactivate() {
    LOGGER.info("Bloodlust slowly disappears.");
  }
}

var enchantedSword = new Sword(new SoulEatingEnchantment());
enchantedSword.wield();
enchantedSword.swing();
enchantedSword.unwield();
// The sword is wielded.
// The item spreads bloodlust.
// The sword is swinged.
// The item eats the soul of enemies.
// The sword is unwielded.
// Bloodlust slowly disappears.
 
var hammer = new Hammer(new FlyingEnchantment());
hammer.wield();
hammer.swing();
hammer.unwield();
// The hammer is wielded.
// The item begins to glow faintly.
// The hammer is swinged.
// The item flies and strikes the enemies finally returning to owner's hand.
// The hammer is unwielded.
// The item's glow fades.