However, the San Francisco court was unable to agree on whether the internet giant's adoption of the programming tools constituted "fair" use and is therefore legal.
Oracle is seeking statutory damages ranging from $200 to $150,000 (£123 to £92,000), but if Google's actions are deemed fair, the company may not be entitled to compensation, Reuters reports.
"There wouldn't be damages, at least on this part, if [Google's] use was determined to be fair. If the fair use defence was upheld, they wouldn't be liable," said Edward Naughton, an attorney who is not involved in the case.
"That's why from a dollars and cents standpoint it's a pretty important argument. I think it's frustratingly inconclusive and we'll have to wait and see how it all comes to a conclusion."
The court was asked to consider four questions on Oracle's claims, but could only agree on three, siding with Google on two of them. The search engine firm is calling for a mistrial to be declared.
Oracle's allegations that Android violates two of its Java patents will be investigated by the same jury in the second phase of the trial.