这系列文章是自己学习研究jmeter源码后的结果，这篇文章介绍的是jmeter界面以及事件响应相关的东西，写下来分享也利于回头看，

下图是jmeter源码导入neatbeans

涉及到跟gui相关的内容大体都在core里面的gui包下

涉及到的类主要有

AbstractJMeterGuiComponent

GUIFactory

GuiPackage

MainFrame

MenuFactory 动态加载类路径下继承了AbstractJmeterGuiComponent或者实现了TestBean接口的类，他们就是MainFrame中右边的Frame

实现TestBean接口的类会有个BeanInfo于之相对应，这是javabean规范，重点是用到了Introspector

gui.action包下面

Command和各种实现了Command接口的类

ActionRouter 动态加载实现了Command接口的类，通过ActionEvent的name来匹配是哪个类响应MainFrame中左边树的相关事件

gui.tree包下面

MainFrame左边的树，重点是TreeNode存了各种testelement,比如controller、sampler、preprocess、config etc.当运行测试的时候，程序就读取里面的各种testelement元素来执行测试流程

界面涉及相关流程

实例化树

MainFrame实例化的时候，会通过调用makeTree方法传入JMeterTreeModel和JMeterTreeListener构建一个JTree,初始化有两个节点

1 private void initTree(TestElement tp, TestElement wb) { 2         // Insert the test plan node 3         insertNodeInto(new JMeterTreeNode(tp, this), (JMeterTreeNode) getRoot(), 0); 4         // Insert the workbench node 5         insertNodeInto(new JMeterTreeNode(wb, this), (JMeterTreeNode) getRoot(), 1); 6         // Let others know that the tree content has changed. 7         // This should not be necessary, but without it, nodes are not shown when the user 8         // uses the Close menu item 9         nodeStructureChanged((JMeterTreeNode)getRoot());10     }

这是JMeterTreeModel中的方法，这个方法会被JMeterTreeModel构造方法调用

1 public JMeterTreeModel() {2         this(new TestPlanGui().createTestElement(),new WorkBenchGui().createTestElement());3 4     }

TestPlanGui和WorkBeanchGui都是继承了AbstractJMeterGuiComponent的类，这是MainFrame中右边界面元素都要继承的类

里面有通用发放，界面执行流程会调用到

tree响应鼠标右键事件弹出菜单

看JMeterTreeListener类，实现了TreeSelectionListener, MouseListener, KeyListener接口

因此响应鼠标右键的事件就是在这处理的

1 @Override 2     public void mousePressed(MouseEvent e) { 3         // Get the Main Frame. 4         MainFrame mainFrame = GuiPackage.getInstance().getMainFrame(); 5         // Close any Main Menu that is open 6         mainFrame.closeMenu(); 7         int selRow = tree.getRowForLocation(e.getX(), e.getY()); 8         if (tree.getPathForLocation(e.getX(), e.getY()) != null) { 9             log.debug("mouse pressed, updating currentPath");10             currentPath = tree.getPathForLocation(e.getX(), e.getY());11         }12         if (selRow != -1) {13             // updateMainMenu(((JMeterGUIComponent)14             // getCurrentNode().getUserObject()).createPopupMenu());15             if (isRightClick(e)) {16                 if (tree.getSelectionCount() < 2) {17                     tree.setSelectionPath(currentPath);18                 }19                 log.debug("About to display pop-up");20                 displayPopUp(e);//这里21             }22         }23     }

1 private void displayPopUp(MouseEvent e) {2         JPopupMenu pop = getCurrentNode().createPopupMenu();3         GuiPackage.getInstance().displayPopUp(e, pop);4     }

JMeterTreeNode中的createPopupMenu方法

1 public JPopupMenu createPopupMenu() {2         try {3             return GuiPackage.getInstance().getGui(getTestElement()).createPopupMenu();4         } catch (Exception e) {5             log.error("Can't get popup menu for gui", e);6             return null;7         }8     }

最后shift+鼠标来到了JMeterGUIComponent接口,恩好吧,这是IDE

找一个实现了这个接口的类，AbstractControllerGui....

1 @Override2     public JPopupMenu createPopupMenu() {3         return MenuFactory.getDefaultControllerMenu();4     }

看MenuFactory类

有个static块，调用了静态方法initializeMenus

1 List
     
       guiClasses = ClassFinder.findClassesThatExtend(JMeterUtils.getSearchPaths(), new Class[] { 2                     JMeterGUIComponent.class, TestBean.class }); 3             Collections.sort(guiClasses); 4             for (String name : guiClasses) { 5  6                 /* 7                  * JMeterTreeNode and TestBeanGUI are special GUI classes, and 8                  * aren't intended to be added to menus 9                  *10                  * TODO: find a better way of checking this11                  */12                 if (name.endsWith("JMeterTreeNode") // $NON-NLS-1$13                         || name.endsWith("TestBeanGUI")) {
   // $NON-NLS-1$14                     continue;// Don't try to instantiate these15                 }16 17                 if (elementsToSkip.contains(name)) { // No point instantiating class18                     log.info("Skipping " + name);19                     continue;20                 }21 22                 boolean hideBean = false; // Should the TestBean be hidden?23 24                 JMeterGUIComponent item;25                 try {26                     Class
       c = Class.forName(name);27                     if (TestBean.class.isAssignableFrom(c)) {28                         TestBeanGUI tbgui = new TestBeanGUI(c);29                         hideBean = tbgui.isHidden() || (tbgui.isExpert() && !JMeterUtils.isExpertMode());30                         item = tbgui;31                     } else {32                         item = (JMeterGUIComponent) c.newInstance();33                     }34                 } catch (NoClassDefFoundError e) {35                     log.warn("Missing jar? Could not create " + name + ". " + e);36                     continue;37                 } catch (Throwable e) {38                     log.warn("Could not instantiate " + name, e);39                     if (e instanceof Error){40                         throw (Error) e;41                     }42                     if (e instanceof RuntimeException){43                         if (!(e instanceof HeadlessException)) { // Allow headless testing44                             throw (RuntimeException) e;45                         }46                     }47                     continue;48                 }
     

会扫描实现了JMeterGUIComponent的接口或者实现了TestBean接口(上面提到的利用了JavaBean规范,BeanInfo哦)的类,

首先Class.forName他们

对于实现接口TestBean的类，会用TestBeanGUI进行包装(我能说这是装饰模式吗？)

然后调用getMenuCategories方法(实现了JMeterGUIComponent接口都会实现这个方法),

这个方法就是告诉当在currentNode上右键鼠标，针对于这个node会弹出的菜单即所谓的PopupMenu

1 if (categories == null) { 2                     log.debug(name + " participates in no menus."); 3                     continue; 4                 } 5                 if (categories.contains(THREADS)) { 6                     threads.add(new MenuInfo(item, name)); 7                 } 8                 if (categories.contains(FRAGMENTS)) { 9                     fragments.add(new MenuInfo(item, name));10                 }11                 if (categories.contains(TIMERS)) {12                     timers.add(new MenuInfo(item, name));13                 }14 15                 if (categories.contains(POST_PROCESSORS)) {16                     postProcessors.add(new MenuInfo(item, name));17                 }18 19                 if (categories.contains(PRE_PROCESSORS)) {20                     preProcessors.add(new MenuInfo(item, name));21                 }22 23                 if (categories.contains(CONTROLLERS)) {24                     controllers.add(new MenuInfo(item, name));25                 }26 27                 if (categories.contains(SAMPLERS)) {28                     samplers.add(new MenuInfo(item, name));29                 }30 31                 if (categories.contains(NON_TEST_ELEMENTS)) {32                     nonTestElements.add(new MenuInfo(item, name));33                 }34 35                 if (categories.contains(LISTENERS)) {36                     listeners.add(new MenuInfo(item, name));37                 }38 39                 if (categories.contains(CONFIG_ELEMENTS)) {40                     configElements.add(new MenuInfo(item, name));41                 }42                 if (categories.contains(ASSERTIONS)) {43                     assertions.add(new MenuInfo(item, name));44                 }

然后对应TestElement的gui类中的createPopUp方法就会在这里来取他们对应的菜单项目

弹出菜单项的响应鼠标单击事件

看MenuFactory中的各种makeMenus方法，makeMenuItem是最小项即创建每个弹出菜单最后一项内容

1 public static JMenuItem makeMenuItem(String label, String name, String actionCommand) { 2         JMenuItem newMenuChoice = new JMenuItem(label); 3         newMenuChoice.setName(name); 4         newMenuChoice.addActionListener(ActionRouter.getInstance()); 5         if (actionCommand != null) { 6             newMenuChoice.setActionCommand(actionCommand); 7         } 8  9         return newMenuChoice;10     }

newMenuChoice.addActionListener(ActionRouter.getInstance());

这句话设置了每个菜单项响应事件的监听器，已经actioncommand即该菜单项的command名字

定位到ActionRouter类，他是一个单例类，看他的方法populateCommandMap

1 List
     
       listClasses = ClassFinder.findClassesThatExtend( 2                     JMeterUtils.getSearchPaths(), // strPathsOrJars - pathnames or jarfiles to search for classes 3                     // classNames - required parent class(es) or annotations 4                     new Class[] {Class.forName("org.apache.jmeter.gui.action.Command") }, // $NON-NLS-1$ 5                     false, // innerClasses - should we include inner classes? 6                     null, // contains - classname should contain this string 7                     // Ignore the classes which are specific to the reporting tool 8                     "org.apache.jmeter.report.gui", // $NON-NLS-1$ // notContains - classname should not contain this string 9                     false); // annotations - true if classnames are annotations10             commands = new HashMap
      
       >(listClasses.size());11             if (listClasses.isEmpty()) {12                 log.fatalError("!!!!!Uh-oh, didn't find any action handlers!!!!!");13                 throw new JMeterError("No action handlers found - check JMeterHome and libraries");14             }15             for (String strClassName : listClasses) {16                 Class
        commandClass = Class.forName(strClassName);17                 Command command = (Command) commandClass.newInstance();18                 for (String commandName : command.getActionNames()) {19                     Set
        commandObjects = commands.get(commandName);20                     if (commandObjects == null) {21                         commandObjects = new HashSet
       ();22                         commands.put(commandName, commandObjects);23                     }24                     commandObjects.add(command);25                 }26             }
      
     

搜集实现了Command接口的各种类，这些类就是响应菜单单击事件的类，他们都在org.apache.jmeter.gui.action包下，当然我们可以实现我们自己的Command，

简单的看其中一个 AboutCommand

1 static { 2         HashSet
     
       commands = new HashSet
      
       (); 3         commands.add(ActionNames.ABOUT); 4         commandSet = Collections.unmodifiableSet(commands); 5     } 6  7     /** 8      * Handle the "about" action by displaying the "About Apache JMeter..." 9      * dialog box. The Dialog Box is NOT modal, because those should be avoided10      * if at all possible.11      */12     @Override13     public void doAction(ActionEvent e) {14         if (e.getActionCommand().equals(ActionNames.ABOUT)) {15             this.about();16         }17     }18 19     /**20      * Provide the list of Action names that are available in this command.21      */22     @Override23     public Set
       
         getActionNames() {24         return AboutCommand.commandSet;25     }
       
      
     

doAction方法处理单击事件的地方

getActionNames方法是ActionRouter用来调用的,

ActionRouter中收集Command的代码

1 for (String commandName : command.getActionNames()) {2                     Set commandObjects = commands.get(commandName);3                     if (commandObjects == null) {4                         commandObjects = new HashSet();5                         commands.put(commandName, commandObjects);6                     }7                     commandObjects.add(command);8                 }