How can I intercept CTRL+V keypress and then alert what was pasted using JavaScript or jQuery?

Question

I want to do the following:

• User presses CTRL V while focused on the
  webpage
• Page intercepts it and shows an alert with what the user has tried to paste

For example:

• User has "foo" in clipboard
• User presses CTRL V while focused on the webpage
• Page shows an alert with "foo" in it

I am new to JavaScript and jQuery, and I am not sure how can I implement this. Any help will be appreciated. Thanks!