Eclipse插件：如何获取当前选定项目的路径

Question

我正在编写一个Eclipse插件，该插件将在Java项目的上下文菜单中显示一个菜单项。 我编写了以下plugin.xml：

<plugin>
   <extension
         point="org.eclipse.ui.menus">
      <menuContribution
            locationURI="popup:org.eclipse.jdt.ui.PackageExplorer">
         <dynamic
               class="uk.co.dajohnston.plugin.classpathswitcher.menu.MenuContribution"
               id="uk.co.dajohnston.plugin.classpathSwitcher.switchMenuContribution">
            <visibleWhen>
               <with
                     variable="activeMenuSelection">
                  <iterate>
                     <adapt
                           type="org.eclipse.jdt.core.IJavaProject">
                     </adapt>
                  </iterate>
                  <count
                        value="1">
                  </count>
               </with>
            </visibleWhen>
         </dynamic>
      </menuContribution>
   </extension>

</plugin>

我正在尝试编写MenuContribution类，它扩展了CompoundContributionItem，以便创建一个动态菜单，该菜单的内容基于存在于Java项目根目录中的一组文件。但是，我在尝试从getContributionItems方法中获取根目录路径时遇到了困难。

基于plugin.xml文件，可以保证只有选择单个Java项目时才会调用这种方法，因此我只需要获取当前选择并获取其绝对路径。有什么想法吗？或者有更好的方法吗？

- DaveJohnston

Answer 1

这应该能让你更接近解决方案（如果不能完全解决的话 ;))

    IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
    if (window != null)
    {
        IStructuredSelection selection = (IStructuredSelection) window.getSelectionService().getSelection();
        Object firstElement = selection.getFirstElement();
        if (firstElement instanceof IAdaptable)
        {
            IProject project = (IProject)((IAdaptable)firstElement).getAdapter(IProject.class);
            IPath path = project.getFullPath();
            System.out.println(path);
        }
    }

- sgibly

---

谢谢，它带我到了目的地。getFullPath()似乎只返回项目的名称，但getLocation()返回完整的绝对路径。 - DaveJohnston

我尝试了这个，但是Eclipse无法解析IProject，你有什么想法吗？谢谢。 - Apperside

有一段时间了...你检查过你得到的IAdaptable类型了吗？另外，你在项目视图中有任何选择吗？ - sgibly

Answer 2

自从我写了上一个答案之后，我又写了另外几个实用程序插件，并且现在拥有了Eclipse导航器弹出窗口的通用启动程序。 文件如下：

基本清单文件

MANIFEST.MF

Manifest-Version: 1.0
Bundle-ManifestVersion: 2
Bundle-Name: NavigatorPopup
Bundle-SymbolicName: com.nsd.NavigatorPopup;singleton:=true
Bundle-Version: 1.0.0.1
Bundle-Vendor: NSD
Require-Bundle: org.eclipse.ui,
 org.eclipse.core.resources,
 org.eclipse.core.runtime
Bundle-RequiredExecutionEnvironment: JavaSE-1.6

基本的属性文件

build.properties

source.. = src/
output.. = bin/
bin.includes = plugin.xml,\
               META-INF/,\
               .

插件文件

需要特别注意在<menuContribution...> <menu..>中的<command commandId=...>，它在扩展点<extension point="org.eclipse.ui.menus">中链接到了<extension point="org.eclipse.ui.handlers">中的<handler commandId=...>，这使得我们可以将多个菜单贡献链接到一个处理程序。

还值得注意的是，有多个locationURI，因为这些可以从一个透视图更改为另一个透视图。

plugin.xml

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.4"?>
<plugin>
    <extension point="org.eclipse.ui.commands">
        <category name="NSD Category" id="com.nsd.NavigatorPopup.commands.category"/>
        <command name="Navigator Popup" categoryId="com.nsd.NavigatorPopup.commands.category" id="com.nsd.NavigatorPopup.commands.navigatorPopupCommand"/>
    </extension>
    <extension point="org.eclipse.ui.handlers">
        <handler commandId="com.nsd.NavigatorPopup.commands.navigatorPopupCommand" class="com.nsd.navigatorpopup.NavigatorPopupHandler"/>
    </extension>
    <extension point="org.eclipse.ui.menus">
        <menuContribution locationURI="popup:org.eclipse.jdt.ui.PackageExplorer?after=additions">
            <menu label="Popup Utilities">
                <command commandId="com.nsd.NavigatorPopup.commands.navigatorPopupCommand" id="com.nsd.NavigatorPopup.menus.navigatorPopupCommand"/>
            </menu>
        </menuContribution>
        <menuContribution locationURI="popup:org.eclipse.ui.navigator.ProjectExplorer#PopupMenu?after=additions">
            <menu label="Popup Utilities">
                <command commandId="com.nsd.NavigatorPopup.commands.navigatorPopupCommand" id="com.nsd.NavigatorPopup.menus.navigatorPopupCommand"/>
            </menu>
        </menuContribution>
    </extension>
</plugin>

要了解有关当前选择的插件的更多信息，请单击文件并使用 ALT-SHIFT-F1 进行“插件选择侦察器”。

使用 ALT-SHIFT-F2 进行“插件菜单侦察器”。请注意，在右键单击并选择感兴趣的弹出菜单项之前，按下 ALT-SHIFT-F2 组合键。

最后是插件代码。

NavigatorPopupHandler.java

package com.nsd.navigatorpopup;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.handlers.HandlerUtil;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ITreeSelection;
import org.eclipse.jface.viewers.TreePath;
import org.eclipse.jface.viewers.TreeSelection;

// ====================================================================================================================
// This handler will obtain the core information about a file from a navigator popup menu
// ====================================================================================================================
public class NavigatorPopupHandler extends AbstractHandler {
    private IWorkbenchWindow window;
    private IWorkbenchPage activePage;

    private IProject theProject;
    private IResource theResource;
    private IFile theFile;

    private String workspaceName;
    private String projectName;
    private String fileName;

    public NavigatorPopupHandler() {
        // Empty constructor
    }

    public Object execute(ExecutionEvent event) throws ExecutionException {
        // Get the project and file name from the initiating event if at all possible
        if(!extractProjectAndFileFromInitiatingEvent(event)) {
            return null;
        }

        // CODE THAT USES THE FILE GOES HERE
        MessageDialog.openInformation(this.window.getShell(), "NavigatorPopup", String.format("File Details.\n\nWorkspace=%s\nProject=%s\nFile=%s", workspaceName, projectName, fileName));

        return null;
    }

    private boolean extractProjectAndFileFromInitiatingEvent(ExecutionEvent event) {
        // ============================================================================================================
        // The execute method of the handler is invoked to handle the event. As we only contribute to Explorer
        // Navigator views we expect to get a selection tree event
        // ============================================================================================================
        this.window = HandlerUtil.getActiveWorkbenchWindow(event);
        // Get the active WorkbenchPage
        this.activePage = this.window.getActivePage();

        // Get the Selection from the active WorkbenchPage page
        ISelection selection = this.activePage.getSelection();
        if(selection instanceof ITreeSelection) {
            TreeSelection treeSelection = (TreeSelection) selection;
            TreePath[] treePaths = treeSelection.getPaths();
            TreePath treePath = treePaths[0];

            // The TreePath contains a series of segments in our usage:
            // o The first segment is usually a project
            // o The last segment generally refers to the file

            // The first segment should be a IProject
            Object firstSegmentObj = treePath.getFirstSegment();
            this.theProject = (IProject) ((IAdaptable) firstSegmentObj).getAdapter(IProject.class);
            if(this.theProject == null) {
                MessageDialog.openError(this.window.getShell(), "Navigator Popup", getClassHierarchyAsMsg(
                                "Expected the first segment to be IAdapatable to an IProject.\nBut got the following class hierarchy instead.", "Make sure to directly select a file.",
                                firstSegmentObj));
                return false;
            }

            // The last segment should be an IResource
            Object lastSegmentObj = treePath.getLastSegment();
            this.theResource = (IResource) ((IAdaptable) lastSegmentObj).getAdapter(IResource.class);
            if(this.theResource == null) {
                MessageDialog.openError(this.window.getShell(), "Navigator Popup", getClassHierarchyAsMsg(
                                "Expected the last segment to be IAdapatable to an IResource.\nBut got the following class hierarchy instead.", "Make sure to directly select a file.",
                                firstSegmentObj));
                return false;
            }

            // As the last segment is an IResource we should be able to get an IFile reference from it
            this.theFile = (IFile) ((IAdaptable) lastSegmentObj).getAdapter(IFile.class);

            // Extract additional information from the IResource and IProject
            this.workspaceName = this.theResource.getWorkspace().getRoot().getLocation().toOSString();
            this.projectName = this.theProject.getName();
            this.fileName = this.theResource.getName();

            return true;
        } else {
            String selectionClass = selection.getClass().getSimpleName();
            MessageDialog.openError(this.window.getShell(), "Unexpected Selection Class", String.format("Expected a TreeSelection but got a %s instead.\nProcessing Terminated.", selectionClass));
        }

        return false;
    }

    @SuppressWarnings("rawtypes")
    private static String getClassHierarchyAsMsg(String msgHeader, String msgTrailer, Object theObj) {
        String msg = msgHeader + "\n\n";

        Class theClass = theObj.getClass();
        while(theClass != null) {
            msg = msg + String.format("Class=%s\n", theClass.getName());
            Class[] interfaces = theClass.getInterfaces();
            for(Class theInterface : interfaces) {
                msg = msg + String.format("    Interface=%s\n", theInterface.getName());
            }
            theClass = theClass.getSuperclass();
        }

        msg = msg + "\n" + msgTrailer;

        return msg;
    }
}

运行插件在其自己的Java文件上的结果。

- TJA

Answer 3

经过一整天的查找，我终于找到了解决方案。关键在于通过Java反射循环来研究导航器中选择项的类和接口结构。类内省循环已经被放置在最终位置，但最初它更接近execute方法的顶部。

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.handlers.HandlerUtil;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.ITreeSelection;
import org.eclipse.jface.viewers.TreePath;
import org.eclipse.jface.viewers.TreeSelection;

public class MyHandler extends AbstractHandler {
/**
 * The constructor.
 */
public MyHandler() {
}

public Object execute(ExecutionEvent event) throws ExecutionException {
    IWorkbenchWindow window = HandlerUtil.getActiveWorkbenchWindow(event);
    IWorkbenchPage activePage = window.getActivePage();
    ISelection selection = activePage.getSelection();
    if (selection != null) {
        System.out.println("Got selection");
        if (selection instanceof IStructuredSelection) {
            System.out.println("Got a structured selection");
            if (selection instanceof ITreeSelection) {
                TreeSelection treeSelection = (TreeSelection) selection;
                TreePath[] treePaths = treeSelection.getPaths();
                TreePath treePath = treePaths[0];

                System.out.println("Last");
                Object lastSegmentObj = treePath.getLastSegment();
                Class currClass = lastSegmentObj.getClass();
                while(currClass != null) {
                    System.out.println("  Class=" + currClass.getName());
                    Class[] interfaces = currClass.getInterfaces();
                    for(Class interfacey : interfaces) {
                        System.out.println("   I=" + interfacey.getName());
                    }
                    currClass = currClass.getSuperclass();
                }
                if(lastSegmentObj instanceof IAdaptable) {
                    IFile file = (IFile) ((IAdaptable) lastSegmentObj).getAdapter(IFile.class);
                    if(file != null) {
                        System.out.println("File=" + file.getName());
                        String path = file.getRawLocation().toOSString();
                        System.out.println("path: " + path);
                    }
                }
            }
        }
    }
    return null;
}
}

- TJA