I want to run some hive queries, and then need to collect different metrics like hdfs bytes read/write. For this I have written java code. But before running the code I just want to check if the cloudera services like hive, impala, yarn are running or not. If running then the code need to execute otherwise just exit. Is there any way to check the status of services by java code?
Sampson S gave you a correct answer, but it's not trivial to implement. The information is available via the REST API of the Cloudera Manager (CM) tools offered by Cloudera. You would have your Java program make a web GET request to CM, parse the JSON result and use that to make a decision. Alternatively, you could look at the code behind their APIs to make a more direct query.
But I think you should ask "Why?" What are you trying to accomplish? Are you replicating the functionality already provided by CM? When asking questions here on SO it's always helpful to provide some context. It seems like you may be new to the environment. Perhaps it already does what you want.