Bug 152919 [Import/Export] import existing project w/ copy is inefficient
I just tried to import some existing projects and selected "copy projects into workspace". After a long time (sorry, no measurements) I had to cancel the request, because I was running out of disk space. I had just succeeded in importing the first project (jdt core), which takes approx. 80MB disk space, but at that time the previously blank workspace consumed additional 300MB mainly in: .metadata/.plugins/org.eclipse.core.resources/.history/ Is this operation recording undo-information for each single file imported? Unless I made something really stupid, this operation seems not to be usable for large projects.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/wizards/datatransfer/WizardProjectsImportPage.java
monitor.worked(50);
						monitor
								.subTask(DataTransferMessages.WizardProjectsImportPage_ProcessingMessage);
						while (filesIterator.hasNext()) {
							File file = (File) filesIterator.next();
							selectedProjects[index] = new ProjectRecord(file);
							index++;
						}
					} else {
						monitor.worked(60);
					}
					monitor.done();
				}
			});
		} catch (InvocationTargetException e) {
			IDEWorkbenchPlugin.log(e.getMessage(), e);
		} catch (InterruptedException e) {
			
		}
		projectsList.refresh(true);
		projectsList.setCheckedElements(getValidProjects());
		setPageComplete(projectsList.getCheckedElements().length > 0);
	}
	/**
	 * Answer a handle to the zip file currently specified as being the source.
	 * Return null if this file does not exist or is not of valid format.
	 */
	private ZipFile getSpecifiedZipSourceFile(String fileName) {
		if (fileName.length() == 0) {
			return null;