535. Encode and Decode TinyURL

TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com/problems/design-tinyurl and it returns a short URL such as http://tinyurl.com/4e9iAk.

Design the encode and decode methods for the TinyURL service. There is no restriction on how your encode/decode algorithm should work. You just need to ensure that a URL can be encoded to a tiny URL and the tiny URL can be decoded to the original URL.

题目含义：设计一个短网址的编码和解码系统

public class Codec {
    Map<Integer, String> map = new HashMap<>();
    
    // Encodes a URL to a shortened URL.
    public String encode(String longUrl) {
        map.put(longUrl.hashCode(),longUrl);
        return "http://tinyurl.com/"+longUrl.hashCode();        
    }

    // Decodes a shortened URL to its original URL.
    public String decode(String shortUrl) {
        return map.get(Integer.parseInt(shortUrl.replace("http://tinyurl.com/", "")));        
    }
}