我推荐PlantUML。这个工具非常有用，很容易使用。PlantUML有一个Netbeans插件，你可以用你的java代码创建UML图。

在netbeans中安装PlantUML插件的方法如下:

Netbeans菜单->工具->插件

现在选择可用插件，然后找到PlantUML并安装它。

更多信息请访问网站:www.plantuml.com

有一个名为binarydoc的免费工具，它可以从Java方法的字节码(而不是源代码)生成UML序列图或控制流图(CFG)。

下面是为java方法java.net.AbstractPlainSocketImpl.getInputStream生成的示例图binarydoc:

方法控制流图:

方法的UML序列图:

PlantUML怎么样? 这不是逆向工程!!这是在编码之前的工程设计。

我是作者之一，所以答案可能有偏见。它是开源的(Apache 2.0)，但是插件不是免费的。如果你克隆并在本地构建它，你就不需要付费。

在Intellij IDEA上，ZenUML可以从Java代码生成序列图。

请登录https://plugins.jetbrains.com/plugin/12437-zenuml-support查看

源代码:https://github.com/ZenUml/jetbrains-zenuml

ObjectAid UML Explorer

是我用的。它很容易从存储库安装:

Name:     ObjectAid UML Explorer
Location: http://www.objectaid.com/update/current

并生成相当不错的UML图:

网站描述:

The ObjectAid UML Explorer is different from other UML tools. It uses the UML notation to show a graphical representation of existing code that is as accurate and up-to-date as your text editor, while being very easy to use. Several unique features make this possible: Your source code and libraries are the model that is displayed, they are not reverse engineered into a different format. If you update your code in Eclipse, your diagram is updated as well; there is no need to reverse engineer source code. Refactoring updates your diagram as well as your source code. When you rename a field or move a class, your diagram simply reflects the changes without going out of sync. All diagrams in your Eclipse workspace are updated with refactoring changes as appropriate. If necessary, they are checked out of your version control system. Diagrams are fully integrated into the Eclipse IDE. You can drag Java classes from any other view onto the diagram, and diagram-related information is shown in other views wherever applicable.

我发现绿色插件非常简单，使用和生成类图从源代码。 试一试吧。 只需将插件复制到插件目录。