java - 无法从Object到IProject强制转换或instanceof为true Java Eclipse插件开发

为什么不能将对象类型的数组（用于获取选择包浏览器的Eclipse框架方法返回）的内容转换为IProject？ instanceof返回false，并且不检查就强制转换会导致异常。但是调试器将Object []数组的内容显示为具有所有实例变量和IProject类型的所有内容：

private List<IProject> getValidSelectedProjects(IWorkbenchWindow window) {
        final ISelectionService service = window.getSelectionService();
        final IStructuredSelection structured = (IStructuredSelection) service.getSelection("org.eclipse.jdt.ui.PackageExplorer");
        if (structured == null){
            return null;
        } else {
            final Object[] selectedProjects = structured.toArray();
            ArrayList<IProject> validatedProjects = new ArrayList<IProject>();
            for (final Object projectObj : selectedProjects){
                 if (projectObj instanceof IProject){
                    IProject project = (IProject) projectObj;
                    //do something
                    }
 //rest of the method; returning list of validated projects

我也试过
How to convert between an Object[] and an interface (IProject[]) in Java?

但是我在这行得到一个异常：

System.arraycopy(objectarray, 0, projectarray, 0, objectarray.length);

最佳答案

getSelection()返回的用户界面对象通常不是IProject，IFile或IResource的直接实例。

要获取IProject ...，请使用IAdapterManager：

IProject project = (IProject)Platform.getAdapterManager().getAdapter(projectObj, IProject.class);

有时，对象不提供直接连接到IProject的适配器，因此请尝试更通用的IResource：

IResource resource = (IResource)Platform.getAdapterManager().adapt(projectObj, IResource.class);

if (resource instanceof IProject)
 {
   IProject project = (IProject)resource;

   ... your code
 }