Useful Code Snippets fot Eclipse Plugins

editor.java

void addSlice(IWorkbenchWindow workbench) {
	IEditorPart editor = null;
	for (IWorkbenchPage p : workbench.getPages()) {
		editor = p.getActiveEditor();
		if (editor != null) {
			System.out.println("ED " + p.getLabel());
		}
	}
	if (editor == null) {
		System.err.println("Can not find any editors, skipped.");
		return;
	}
	
	// First get editor filename
	// 	reference: http://stackoverflow.com/a/943348/462865
	IEditorInput input = editor.getEditorInput();
	String fl = "";
	if (input instanceof IFileEditorInput) {
        fl = ((IFileEditorInput)input).getFile().getLocation().toOSString();
        System.out.println("filename: " + fl);
    }
	if (fl.isEmpty()) {
		System.err.println("can not get editor filename");
		return;
	}
	if (!(editor instanceof AbstractTextEditor)) {
		System.err.println("Not in a text editor, no code copied.");
		return;
	}
	
	// Get Selected Function From Editor Selection
	ITextSelection textSelection = (ITextSelection) editor.getSite().getSelectionProvider().getSelection();
	String fn = "";
	boolean fnSelected = true;
	try {
		fn = textSelection.getText();
	} catch (Exception e) {
		fnSelected = false;	
	}
	if (fn.isEmpty()) {
		fnSelected = false;
	}
	
	// Fallback to the text-box if nothing is selected
	if (fnSelected) {
		sliceFuncText.setText(fn);
	} else {
		System.out.print("!");
		fn = sliceFuncText.getText();
	}
	if (fn.isEmpty()) {
		Logger.get().log("no function selected");
		sliceFuncText.setBackground(new Color(255, 120, 180));
		return;
	} else {
		sliceFuncText.setBackground(new Color(255, 255, 255));
	}
}

http.java

public ArrayList<Item> search() {
	Logger.get().log("Search: " + searchExpression);
	
	CloseableHttpClient httpClient = HttpClients.createDefault();
	generateURL();
	Logger.get().log("debug", "query=" + url);
	HttpGet httpGet = new HttpGet(url);
	HttpResponse response = null;
	try {
		response = httpClient.execute(httpGet);
	} catch (IOException e1) {
		e1.printStackTrace();
	}
	Logger.get().profile("retreived");
	
	HttpEntity entity = null;
	try	{
		entity = response.getEntity();
	} catch(NullPointerException n) {
		System.out.println("no internet connection!");
		return null;
	}
	
	java.io.InputStream is = null;
	try {
		is = entity.getContent();
	} catch (IllegalStateException | IOException e1) {
		e1.printStackTrace();
	}
	BufferedReader reader = new BufferedReader(new InputStreamReader(is));
	StringBuilder sb = new StringBuilder();

	String line = null;
	try {
		while ((line = reader.readLine()) != null) {
			sb.append((line + "\n"));
		}
	} catch (IOException e) {
		e.printStackTrace();
	} finally {
		try {
			is.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	Logger.get().profile("read");
	Gson gson = new Gson(); // Or use new GsonBuilder().create();
	SearchResults jsonProperties = gson.fromJson(sb.toString(), SearchResults.class); // deserializes JSON into MyClass
	item = jsonProperties.getItems();		
	Logger.get().profile("parsed");
	return (ArrayList<Item>) item;
}