[[java-aggs-bucket-daterange]]
==== Date Range Aggregation

Here is how you can use
{ref}/search-aggregations-bucket-daterange-aggregation.html[Date Range Aggregation]
with Java API.


===== Prepare aggregation request

Here is an example on how to create the aggregation request:

[source,java]
--------------------------------------------------
AggregationBuilder aggregation =
        AggregationBuilders
                .dateRange("agg")
                .field("dateOfBirth")
                .format("yyyy")
                .addUnboundedTo("1950")    // from -infinity to 1950 (excluded)
                .addRange("1950", "1960")  // from 1950 to 1960 (excluded)
                .addUnboundedFrom("1960"); // from 1960 to +infinity
--------------------------------------------------


===== Use aggregation response

Import Aggregation definition classes:

[source,java]
--------------------------------------------------
import org.elasticsearch.search.aggregations.bucket.range.date.DateRange;
--------------------------------------------------

[source,java]
--------------------------------------------------
// sr is here your SearchResponse object
DateRange agg = sr.getAggregations().get("agg");

// For each entry
for (DateRange.Bucket entry : agg.getBuckets()) {
    String key = entry.getKey();                    // Date range as key
    DateTime fromAsDate = entry.getFromAsDate();    // Date bucket from as a Date
    DateTime toAsDate = entry.getToAsDate();        // Date bucket to as a Date
    long docCount = entry.getDocCount();            // Doc count

    logger.info("key [{}], from [{}], to [{}], doc_count [{}]", key, fromAsDate, toAsDate, docCount);
}
--------------------------------------------------

This will basically produce:

[source,text]
--------------------------------------------------
key [*-1950], from [null], to [1950-01-01T00:00:00.000Z], doc_count [8]
key [1950-1960], from [1950-01-01T00:00:00.000Z], to [1960-01-01T00:00:00.000Z], doc_count [5]
key [1960-*], from [1960-01-01T00:00:00.000Z], to [null], doc_count [37]
--------------------------------------------------