elasticsearch json java api

I am perplexing to combine elasticsearch with android app.I need to get a
jsonobject and printout a sum for any id. First we need to try minute java
class.Can we only use json api or is there a elasticsearch api that is
easier.url:http://www.dummy.com:9200/contacts/index/_search
{"took":10,"timed_out":false,"_shards":{"total":5,"successful":5,"failed":0},"hits":{"total":2,"max_score":1.0,"hits":[{"_index":"contacts","_type":"index","_id":"2","_score":1.0,
"_source" : { "id": "c201", "name": "Johnny
Depp", "email": "johnny_depp@gmail.com",
"address": "xx-xx-xxxx,x - street, x - country", "gender" :
"male", "phone": { "mobile": "+91
0000000000", "home": "00 000000",
"office": "00 000000" }
}},{"_index":"contacts","_type":"index","_id":"1","_score":1.0, "_source"
: { "id": "c200", "name": "Ravi Tamada",
"email": "ravi@gmail.com", "address":
"xx-xx-xxxx,x - street, x - country", "gender" : "male",
"phone": { "mobile": "+91 0000000000",
"home": "00 000000", "office": "00
000000" }}}]}}