使用plantUML绘制类关系图

使用plantUML绘制类关系图

参考：https://plantuml.com/class-diagram

https://en.wikipedia.org/wiki/Class_diagram

下面这个讲的挺好的：

https://misomiso43.medium.com/%E7%B0%A1%E5%96%AE%E7%90%86%E8%A7%A3-uml-%E9%A1%9E%E5%88%A5%E5%9C%96-f0b32a3272c 

 

 

 

Dependency:

A dependency is a type of association where there is a semantic connection between dependent and independent model elements.^[7] It exists between two elements if changes to the definition of one element (the server or target) may cause changes to the other (the client or source). This association is uni-directional. A dependency is displayed as a dashed line with an open arrow that points from the client to the supplier.

一种关联类型。 在依赖和独立的模块之间存在“语义联系”。 如果（server或者target）发生了变动，会影响到（client或source），这种关系是单向的。  dashed line （虚线）和open arrow表示。

在代码中，某个类的方法通过局部变量、方法的参数或者对静态方法的调用来访问另一个类（被依赖类）中的某些方法来完成一些职责。

Association   关联 

Aggregation  聚合 has-a

教授有多个学生去教学 

Class diagram showing Aggregation between two classes. Here, a Professor 'has a' class to teach.

Composition 组合  整体和部分的关系。

Differences between Composition and Aggregation

Composition relationship

1. When attempting to represent real-world whole-part relationships, e.g. an engine is a part of a car. （现实世界的整体-部分关系时，例如发动机是汽车的一部分）

2. When the container is destroyed, the contents are also destroyed, e.g. a university and its departments. （当container被摧毁时，里面的东西也被摧毁，例如一所大学及其院系。）

Aggregation relationship

1. When representing a software or database relationship, e.g. car model engine ENG01 is part of a car model CM01, as the engine, ENG01, maybe also part of a different car model 

（表示软件或数据库关系时，例如，汽车模型引擎ENG01是汽车模型CM01的一部分，因为引擎ENG01也可能是另一个汽车模型的一部分）

2. When the container is destroyed, the contents are usually not destroyed, e.g. a professor has students; when the professor leaves the university the students do not leave along with them.

 （当container被摧毁时，里面的东西通常不会被摧毁，例如，一位教授有学生;当教授离开大学时，学生们并没有跟着他们离开。）

Realization/Implementation  继承 应用

plantUML的快捷方式：

一：Relations between classes

1. Extension <|--            

Generalization/Inheritance  泛化 继承  is-a

abstract A <|-- class B    B继承父A    

 

2.Composition *--      

Car  *--  Carburetor   Carburetor是Car的一部分   

 

3.Aggregation  o-- 

聚合

Professor o-- students   Professor教学多个student

 

二：Label on relations

It is possible to add a label on the relation,using 
:, followed by the text of the label. 
（:可以在关系线上添加文本）

For cardinality, you can use double-quotes 
"" on each side of the relation.
在一端使用""可以在关系线的一端标记
@startuml

Class01 "1" *-- "many" Class02 : contains

Class03 o-- Class04 : aggregation

Class05 --> "1" Class06

@enduml

 

You can add an extra arrow pointing at one object showing which object acts on the other object, using < or > at the begin or at the end of the label.

 使用< 或 >可以指定文本的方向

@startuml
class Car

Driver - Car : drives >
Car *- Wheel : have 4 >
Car -- Person : < owns

@enduml

Adding methods

@startuml
class Dummy {
  String data
  void methods()
}

class Flight {
   flightNumber : Integer
   departureTime : Date
}
@enduml

 

 

Packages

 

You can define a package using the package keyword, and optionally declare a background color for your package (Using a html color code or name).

 

Note that package definitions can be nested.

 

@startuml

package "Classic Collections" #DDDDDD {
  Object <|-- ArrayList
}

package com.plantuml {
  Object <|-- Demo1
  Demo1 *- Demo2
}

@enduml

 

 

 

Changing arrows orientation

By default, links between classes have two dashes -- and are vertically oriented. It is possible to use horizontal link by putting a single dash (or dot) like this:

两个--是竖直的  一个-是水平的

 

@startuml
Room *-- Chair 
Room o- Student
@enduml

 

 左右名称的互换，映射图中的位置，如下两个图的区别:

@startuml
Room *- Chair 
Room o- Student   
@enduml

 

@startuml
Chair -* Room
Room o- Student
@enduml

 

 

It is also possible to change arrow direction by adding left, right, up or down keywords inside the arrow:

使用 left, right, up or down 关键字也可以控制箭头的方式

@startuml
foo -left-> dummyLeft
foo -right-> dummyRight
foo -up-> dummyUp
foo -down-> dummyDown
@enduml

 

 

 

 

Arrows from/to class members

@startuml
class Foo {
+ field1
+ field2
}

class Bar {
+ field3
+ field4
}

Foo::field1 --> Bar::field3 : foo
Foo::field2 --> Bar::field4 : bar
@enduml