We Keep Coding

How to parse the where clause in java into elastic query

I am getting below where clause from client and I want to convert that into elastic search understandable format.
I want to know is there any library available to parse such kind of where clause and convert into ELK search format.
where keywords~'some thning here' AND Status='LIVE' AND ( name='RSP,RFP' OR (user='teacher' AND source='my uploads')) AND (version='1' OR version!=0)

How to convert a hive string query into abstract syntax tree using Java API?

I know I can get the AST using the explain extended command. My question is, how to get the same using the Java API.
My goal is to get the following data about queries:
Database source and target (if applied).
Table source and target (if applied).
Fields involved in the query.
I know I can get them above data directly from query string using Regex, but I want to use Java API.
Do you have any other idea how to do that?

You can use Hive Parser for this. It simply takes the query and convert it into AST which is similar explain command. Here is a simple example:
ParseDriver pd = new ParseDriver();
ASTNode tree = pd.parse("Select * from table1");
System.out.println(tree.dump());
The output for this will be
nil
TOK_QUERY
TOK_FROM
TOK_TABREF
TOK_TABNAME
table1
TOK_INSERT
TOK_DESTINATION
TOK_DIR
TOK_TMP_FILE
TOK_SELECT
TOK_SELEXPR
TOK_ALLCOLREF
<EOF>

elasticsearch | template query | java API

I was trying to implement the feature of template query. Refer to the last section of http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-template.html
I added a query template using sense. Now the need is through JAVA API of elasticsearch, I need to execute this query template and store the result in SearchResponse. However I am not able to find any API related to query Template. The only class file which is available is TemplateQueryBuilder. This class constructs the template query perfectly but I am not sure of which method to be called from Client in order to pass the object of TemplateQueryBuilder.
Help in this is appreciated.

Here is how to do it :
SearchRequestBuilder request = client;.prepareSearch();
request.setTemplateName(templateName);
request.setTemplateType(ScriptService.ScriptType.INDEXED);
request.setTemplateParams(templateParams);
SearchResponse response = request.get();
You just need to parse the response object then ..
refer to: http://www.elasticsearch.org/guide/en/elasticsearch/client/java-api/current/search.html#java-search-template

Note that with API version 2.X, as request.setTemplateX methods are deprecated, you should use a different approach.
Either you can use request.setTemplate(Template template) which is similar to the accepted answer, or you can go with the more generic QueryBuilders approach:
QueryBuilder qb = QueryBuilders.templateQuery(
"templateName",
ScriptService.ScriptType.FILE,
templateParams);
More to read: https://www.elastic.co/guide/en/elasticsearch/client/java-api/2.4/java-specialized-queries.html#java-query-dsl-template-query

MongoDB Java Driver

Given some JSON value and a query in MongoDB format, I want to filter the same way that MongoDB does, the json entities I want without going to the MongoDB.
For example, I have:
JSON Value: [{qty: 10}, {qty: 30}, {qty: 50}]
Query in MongoDB format: { qty: { $gt: 20 } }
Result: [{qty: 50}]
I want that without going to Mongo database, for example calling some method that recives JSON Value and JSON Query String in Mongo format, inside some JAR.
Thanks!

I want that without going to Mongo database
Parse JSON using Jackson and create a Query Object and a Collection containing the target objects.
Use a collections framework such as Guava or GS-Collections and filter.

'Jackson' library offers JSON parsing & generation in Java. Once you've parsed, you can filter values/ data structure using Java code to your heart's content.
Java obviously has no direct implementation of Mongo query language.. you can implement Java code yourself as desired.
See:
http://jackson.codehaus.org/

How to retrieve a subset of fields using the Java MongoDB driver?

new poster here, I found this previous post but it's on C#,
I tried doing this query straight into the java code of a JSP page, for some reason, it doesn't accept the info in the {} of the find() query and just gives out an error...
So peeps, how do I do this in Java:
// retrieve ssn field for documents where last_name == 'Smith':
db.users.find({last_name: 'Smith'}, {'ssn': 1});
Thanks!
PS: why the hell does C# have the nice little .Exclude() and .Include() commands and java doesn't? cries

The java driver follows the exact same API as the shell. Just pass a DBObject containing your field projection as the second argument to find or findOne
As far as I know the official C# driver doesn't expose Include() and Exclude() methods as they violate the standard API.