一、概述

走入Eclipse的内核，看看它到底是怎么工作的？1、Eclipse源代码 下载地址：http://download.eclipse.org/eclipse/downloads2、源代码阅读工具        Source Insight  V3.5它其实是一个代码编辑软件，因为有强大的代码分析工具，可以很方便地跟踪代码的相关性，所以常用来作为阅读代码的工具。下载地址：http://sourceinsight.com/down35.html为了方便代码的分析，我们只提取以下几个插件的代码：org.eclipse.platform                             org.eclipse.platform_3.1.1.jarorg.eclipse.core.commands              org.eclipse.core.commands_3.1.0.jarorg.eclipse.core.expressions            org.eclipse.core.expressions_3.1.0.jarorg.eclipse.core.runtime                     org.eclipse.core.runtime_3.1.1.jarorg.eclipse.help                                    org.eclipse.help_3.1.0.jarorg.eclipse.jface                                   org.eclipse.jface_3.1.1.jarorg.eclipse.osgi                                    org.eclipse.osgi_3.1.1.jarorg.eclipse.swt.win32.win32.x86      org.eclipse.swt.win32.win32.x86_3.1.1.jarorg.eclipse.swt                                     org.eclipse.swt_3.1.0.jarorg.eclipse.ui.workbench                   org.eclipse.ui.workbench_3.1.1.jarorg.eclipse.ui                                        org.eclipse.ui_3.1.1.jarorg.eclipse.update.configurator        org.eclipse.update.configurator_3.1.0.jar将这些代码解压缩到一个空目录里，然后导入到Source Insight的Project里。      二、Eclipse启动过程首先我们从Eclipse的启动过程开始分析。1、eclipse.exe它是Eclipse的启动文件，是与平台相关的可执行文件。它的功能比较简单，主要是加载startup.jar文件，代码在Eclipse源代码的/features/org.eclipse.platform.launchers/library目录下，对应多个平台。对于win32平台，你可以直接运行win32目录下的build.bat文件来编译得到它（需要安装C编译器）。2、startup.jar这个是Eclipse真正的启动文件，你可以在命令行下运行java -jar startup.jar命令来启动Eclipse。它的入口是org.eclipse.core.launcher.Main，它对应的源代码在org.eclipse.platform/src目录的子目录下的Main.java。我们从main函数往后跟踪，找到basicRun，这个是启动的主要部分。protected void basicRun(String[] args) throws Exception {         ......        setupVMProperties();              //设置VM属性        processConfiguration();             //读取configuration/config.ini配置文件        ......        // need to ensure that getInstallLocation is called at least once to initialize the value.        // Do this AFTER processing the configuration to allow the configuration to set        // the install location.          getInstallLocation();        // locate boot plugin (may return -dev mode variations)        URL[] bootPath = getBootPath(bootLocation);        setSecurityPolicy(bootPath);       //设置执行权限        // splash handling is done here, because the default case needs to know        // the location of the boot plugin we are going to use        handleSplash(bootPath);        invokeFramework(passThruArgs, bootPath);            //启动Eclipse内核    }这个函数前面部分是设置一些属性，最关键的是最后invokeFramework函数，它是启动Eclipse的核心。下面我们看看invokeFramework函数的具体内容。private void invokeFramework(String[] passThruArgs, URL[] bootPath) throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, Error, Exception, InvocationTargetException {         ......        URLClassLoader loader = new StartupClassLoader(bootPath, parent);        Class clazz = loader.loadClass(STARTER);             //加载   String STARTER = "org.eclipse.core.runtime.adaptor.EclipseStarter";        Method method = clazz.getDeclaredMethod("run", new Class[] {String[].class, Runnable.class});          //获得run方法        ......        method.invoke(clazz, new Object[] {passThruArgs, endSplashHandler});           //调用run方法        ......    }首先创建加载器loader，它是一个URLClassLoader类型。接着加载类"org.eclipse.core.runtime.adaptor.EclipseStarter"，获得其run方法，然后调用此方法。3、OSGI启动"org.eclipse.core.runtime.adaptor.EclipseStarter"类的源代码位于/plugins/org.eclipse.osgi/eclipseAdaptor/src/org/eclipse/core/runtime/adaptor。可见它已经位于OSGI包内，它是OSGI的启动类。 public static void startup(String[] args, Runnable endSplashHandler) throws Exception {   ......  adaptor = createAdaptor();              //建立适配器  ......  OSGi osgi = new OSGi(adaptor);          //建立OSGI对象，这就是我们要找的东西  ......  osgi.launch();                        //启动OSGI  ......  context = osgi.getBundleContext();        //获得已加载的Bundle的执行上下文  ......  Bundle[] startBundles = loadBasicBundles();   //加载Bundle  setStartLevel(getStartLevel());              //设置启动级别  ...... }    4、Eclipse固定菜单的实现类（如Project、Help等菜单）    org.eclipse.ui.internal.ide包下的WorkbenchActionBuilder.java类中的 protected void fillMenuBar(IMenuManager menuBar)方法，具体实现如下：    protected void fillMenuBar(IMenuManager menuBar) {         menuBar.add(createFileMenu());                                    //在菜单栏增加File菜单        menuBar.add(createEditMenu());        menuBar.add(createNavigateMenu());        menuBar.add(createProjectMenu());        menuBar.add(new GroupMarker(IWorkbenchActionConstants.MB_ADDITIONS));        menuBar.add(createWindowMenu());        menuBar.add(createHelpMenu());    }    如果想去掉File菜单下的Move项可以注掉private MenuManager createFileMenu()方法中的以下语句：    // menu.add(moveAction);