% 51CTO陸巍的博客LaTeX繪制UML類圖示例
\documentclass[oneside, AutoFakeBold]{article}

\usepackage{geometry}          % 用於頁面設置
% 設置為A4紙，並按照MSOffice的默認尺寸設置四周邊距
\geometry{
  a4paper,
  left = 3.17cm,
  right = 3.17cm,
  top = 2.54cm,
  bottom = 2.54cm
}

\usepackage{xeCJK}
% 設置字體。註意順序，第一個定義的就是默認字體
\setCJKfamilyfont{song}{方正書宋簡體}
\newcommand{\song}{\CJKfamily{song}}
\setCJKfamilyfont{kaiti}{方正楷體簡體}
\newcommand{\kaiti}{\CJKfamily{kaiti}}
\setCJKfamilyfont{heiti}{方正黑體簡體}
\newcommand{\heiti}{\CJKfamily{heiti}}

% 支持繪制UML
\usepackage[simplified]{pgf-umlcd}

\begin{document}

\centerline{\huge UML繪制示例}
\quad\\\\heiti\large 示例一：\normalsize
\begin{center}
    \begin{tikzpicture}
      \begin{class}[text width = 3cm]{CheckWriter}{0, 0}
        \operation{+ writeCheck()}
      \end{class}

      \begin{class}[text width = 3cm]{Payroll}{4.5, 0}
      \end{class}

      \begin{class}[text width = 3cm]{Employee}{9, 0}
        \operation{+ calculatePay()}
        \operation{+ postPayment()}
      \end{class}

      \begin{class}[text width = 3cm]{Employee Database}{4.5, -2}
        %\implement{Employee}
        \operation{+ getEmployee()}
        \operation{+ putEmployee()}
      \end{class}

      \unidirectionalAssociation{Payroll}{}{}{CheckWriter}
      \unidirectionalAssociation{Payroll}{}{}{Employee}
      \unidirectionalAssociation{Payroll}{}{}{Employee Database}
      %\draw[umlcd style dashed line, ->](Employee Database.east) -- ++(2.9, 0) -- (Employee.south);
      \draw[umlcd style dashed line, ->](Employee Database) -| (Employee);
    \end{tikzpicture}
    \\ 圖4.1 耦合在一起的薪水支付應用模型
  \end{center}
  \quad\\\  \large 示例二：\normalsize
  \begin{center}
      \begin{tikzpicture}
        \begin{interface}[text width = 2.7cm]{CheckWriter}{0, -2}
          \operation{+ writeCheck()}
        \end{interface}

        \begin{class}[text width = 2.7cm]{Mock CheckWriter}{0, 0}
          \inherit{CheckWriter}
        \end{class}

        \begin{class}[text width = 2.7cm]{PayrollTest}{4, 0}
        \end{class}

        \begin{interface}[text width = 2.7cm]{Employee}{8, -2}
          \operation{+ calculatePay()}
          \operation{+ postPayment()}
        \end{interface}

        \begin{class}[text width = 2.7cm]{Mock Employee}{8, 0}
          \inherit{Employee}
        \end{class}

        \begin{class}[text width = 2.7cm]{Payroll}{4, -2}
        \end{class}

        \begin{interface}[text width = 2.7cm]{Employee Database}{4, -4.5}
          \operation{+ getEmployee()}
          \operation{+ putEmployee()}
        \end{interface}

        \begin{class}[text width = 2.7cm]{Mock Employee Database}{4, -8}
          \inherit{Employee Database}
        \end{class}

        \unidirectionalAssociation{PayrollTest}{}{}{Mock CheckWriter}
        \unidirectionalAssociation{PayrollTest}{}{}{Mock Employee}
        \unidirectionalAssociation{PayrollTest}{}{}{Payroll}
        \unidirectionalAssociation{Payroll}{}{}{CheckWriter}
        \unidirectionalAssociation{Payroll}{}{}{Employee}
        \unidirectionalAssociation{Payroll}{}{}{Employee Database}
        \draw [umlcd style dashed line, ->] (Employee Database) -| (Employee);
        \draw [->](PayrollTest.north) -- ++(0, 0.3) -- ++(6, 0) |- (Mock Employee Database);
      \end{tikzpicture}
      \heiti\\ 圖4.2 使用Mock Objects測試方法，解除了耦合的薪水支付應用模型\song
    \end{center}
\end{document}
 

效果如下：

　
　　這份代碼還是比較容易看懂的，繪制過程大概就是先繪制類，再繪制邊線。說明如下：
　　1.　繪制類時先繪制父類，否則表示繼承關系的線指示會出問題,，其他類型的線也同理；
　　2.　在第一個例子中，繪制虛線時列出了兩種方式，大家註意觀察比較。註釋掉的方法實際上就是使用節點來轉折；
　　3.　註意畫線時節點的坐標，這個坐標是相對坐標，是相對於上一個節點的坐標。例如第二個例子中的“-- ++(0, 0.3) -- ++(6, 0) |-”，(0, 0.3)表示的是相對於PayrollTest.North的坐標位置，而(6, 0)則是相對於(0, 0.3)的位置。
　　4.　節點的四個方向是用英文的東南西北表示，不要弄成上下左右了；

\attribute{owner : String}

LaTeX繪制UML類圖備忘