要了解swt，jface的一些机制，不过大部分都可以查阅资料清楚具体的用法。
这次代码生成插件的开发首先遇到的难点是模块的构建次序，按照jsmart的工作流程，数据库加载，实体构建，包名设定，框架选择。各模块之间的关联处理比较麻烦，主要是一些参数的传递。第一步将框架搭建起来。
第二个难点是plugin.xml的配置，其中runtime的配置没写，也就是插件运行环境的jar包没有加载，是的插件运行时总是报错，这个错误调了很久，破费周折。发现这一类的问题插件本身不会报错，但是会转向event事件的处理，感觉这种错误太隐蔽了。
第三个难点是rcp的路径选择问题。很麻烦，从这个才知道了Eclipse中有一个jdt包，包含了Eclipse工程的很多信息，感觉相当实用。路径的一些现实代码如下：
代码
package testplugin.actions;
import java.net.URL;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.IWorkbenchWindowActionDelegate;
import org.eclipse.ui.internal.UIPlugin;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.adaptor.LocationManager;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.osgi.service.datalocation.Location;
import org.osgi.framework.Bundle;
import testplugin.Activator;
/**
* Our sample action implements workbench action delegate. The action proxy will
* be created by the workbench and shown in the UI. When the user tries to use
* the action, this delegate will be created and execution will be delegated to
* it.
*
* @see IWorkbenchWindowActionDelegate
*/
public class SampleAction implements IWorkbenchWindowActionDelegate {
private IWorkbenchWindow window;
private static IProject project = null;
/**
* The constructor.
*/
public SampleAction() {
}
/**
* The action has been activated. The argument of the method represents the
* 'real' action sitting in the workbench UI.
*
* @see IWorkbenchWindowActionDelegate#run
*/
public void run(IAction action) {
Location installLoc = LocationManager.getInstallLocation();
String path = null;
String installPath = null;
if (installLoc != null) {
URL installURL = installLoc.getURL();
// assume install URL is file: based
path = installURL.getPath();
}
installPath = path.substring(1, path.length());
Bundle bundle = Platform.getBundle("webGenerator");
String bundleLocation = bundle.getLocation();
String resource = SampleAction.class.getResource("generator.properties").toString();
String msg;
msg = "plugin abstract path:" + Activator.getDefault().getStateLocation().makeAbsolute().toFile().getAbsolutePath();
msg += "\nworkspace:" + Platform.getInstanceLocation().getURL().getPath();
msg += "\ninstallPath:" + installPath;
msg += "\n" + UIPlugin.getDefault().getBundle().getHeaders().get("Bundle-Name");
msg += "\n" + bundleLocation;
msg += "\n" + resource;
MessageDialog.openInformation(window.getShell(), "TestPlugin", msg);
}
/**
* Selection in the workbench has been changed. We can change the state of
* the 'real' action here if we want, but this can only happen after the
* delegate has been created.
*
* @see IWorkbenchWindowActionDelegate#selectionChanged
*/
public void selectionChanged(IAction action, ISelection selection) {
// Test project resource selection
if (selection instanceof IStructuredSelection) {
String msg;
IStructuredSelection structuredSelect = (IStructuredSelection) selection;
if (!structuredSelect.isEmpty()) {
Object obj = structuredSelect.getFirstElement();
if (obj instanceof IProject) {
project = ((IProject) obj).getProject();
msg = "getProjectName:" + getProjectName();
msg += "getWorkplaceName:" + getWorkplaceName();
msg += "getProjectPath:" + getProjectPath();
msg += "getPath:" + getPath();
msg += "getPluginPath:" + getPluginPath();
MessageDialog.openInformation(window.getShell(), "TestPlugin", msg);
return;
} else {
System.out.println("The selection is not a project");
}
}
}
}
/**
* We can use this method to dispose of any system resources we previously
* allocated.
*
* @see IWorkbenchWindowActionDelegate#dispose
*/
public void dispose() {
}
/**
* We will cache window object in order to be able to provide parent shell
* for the message dialog.
*
* @see IWorkbenchWindowActionDelegate#init
*/
public void init(IWorkbenchWindow window) {
this.window = window;
}
/**
* 得到项目名称
*
* @return
*/
public static String getProjectName() {
return project.getName();
}
/**
* 得到workplace的运行文件
*
* @return
*/
public static String getWorkplaceName() {
String path = Platform.getInstanceLocation().getURL().getPath();
return path.substring(1, path.length());
}
/**
* 得到project项目的文件路径
*
* @return
*/
public static String getProjectPath() {
return project.getProject().getLocation().toString() + "/";
}
/**
* 得到Eclipse运行目录
*
* @return
*/
@SuppressWarnings("restriction")
public static String getPath() {
Location installLoc = LocationManager.getInstallLocation();
String path = null;
String installPath = null;
if (installLoc != null) {
URL installURL = installLoc.getURL();
// assume install URL is file: based
path = installURL.getPath();
}
installPath = path.substring(1, path.length());
return installPath;
}
/**
* 得到plugin所在的位置，文件夹为.../filename/;jar包为.../filename.jar
*
* @return
*/
public static String getPluginPath() {
Bundle bundle = Platform.getBundle("webGenerator");
String bundleLocation = bundle.getLocation();
String[] items = bundleLocation.split(":");
String pluginLocation = getPath() + items[items.length - 1];
return pluginLocation;
}
}
这次项目对插件的认识姑且就是这些，虽然相当肤浅，不过也算是了解的，感觉Eclipse的却比较强大，java也很强大。感觉像在编程上有所成就真是任重而道远啊。
什么时候要吧Eclipse的框架理一下啊！