Possible to show and store top 3 results of Google Search?

I开发者_JAVA技巧s it possible to show and store the results obtained from a Google Search query? The search is performed from the commons-http client, through my webapp. My questions are:

1. Is it permissible?
2. Is it ethical?
3. Is it possible?

I have heard that google changes tags and blocks scrapers. Is it correct? Any other way to do it?

It is certainly possible to scrape Google for results - many do. You can use proxies to mask your IP and avoid being blocked.

Make sure you set your user-agent to a browser.

Google doesn't like this and provides a search API, but it is pretty useless.