I'm trying to parse some huge JSON file (like http://eu.battle.net/auction-data/258993a3c6b974ef3e6f22ea6f822720/auctions.json) using gson library (http://code.google.com/p/google-gson/) in JAVA.
I would like to know what is the best approch to parse this kind of big file (about 80k lines) and if you may know good API that can help me processing this.
You don't need to switch to Jackson. Gson 2.1 introduced a new TypeAdapter interface that permits mixed tree and streaming serialization and deserialization.
The API is efficient and flexible. See Gson's Streaming doc for an example of combining tree and binding modes. This is strictly better than mixed streaming and tree modes; with binding you don't waste memory building an intermediate representation of your values.
Like Jackson, Gson has APIs to recursively skip an unwanted value; Gson calls this skipValue().