类图

类图

依赖（dependency）--->

public class Animal {

 public void drink(Water water){
      System.out.println("drink water");
  }

}

public class Water {

}

关联（Association）—>

public class TimeCard {
}
public class Employee {
 private TimeCard timeCard;
 //...
}

聚合（Aggregation）◇—>

public class People {
 private Person p;
}
public class Person{
}

合成（Composition）◆—>

合成是聚合的一种特殊形式

public class People {

 private Person p;

 private Person p2;

}

泛化（Generalization）—△

public class Cat extends Animal{

    @Override
 public void drink(Water water) {
     super.drink(water);
    }
}

实现（Realization）----△

public class Cat implements Animal{
 @Override
 public void drink() {
 }
}