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javathriftconcurrenthashmap

Custom container type in Apache Thrift

How can I write a custom container type with Apache Thrift?

I am aware that, by default, any map declaration in Thrift extends HashMap.

Is there a way that I can modify it to extend ConcurrentHashMap instead of HashMap?

For e.g., if Test.thrift is defined as follows:

struct TestData { 1: string id, 2: map details }

How can I make sure that this map is implemented as a ConcurrentHashMap?

Thanks!

Solution

  • There are tree predefined container types (list<R>, set<T> and map<K,V>), which are tied to a suitable, language specific implementation.

    While Thrift does enable you to freely construct structs in a lot of ways, there is no extension to the basic IDL data types and containers.

    Some language bindings, like C++, allow customisation of container implementation (i.e. which classes are actually used in the generated code) by means of IDL annotations. However, this is supported only with a small subset of the languages and AFAIK Java is NOT one of them.

    How can I make sure that this map is implemented as a ConcurrentHashMap?

    You need to change the Thrift compiler or post-process the generated code artifacts somehow.