Google Ad Exchange uses protobuf through the HTTP Post and has its own models. However, they have now released openrtb-doubleclick , which allows you to easily convert your queries to standard OpenRTB and vice versa.
If you use maven you can use
<dependency> <groupId>com.google.doubleclick</groupId> <artifactId>doubleclick-openrtb</artifactId> <version>0.6.5</version> </dependency>
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