Dubbo : cross-system communication. For example: two systems, a system A as a client, a server for the system B, the server B to define its own interface to the client A, the A interface definition in the spring bean client. A client can directly use this bean, if implementations of these interfaces (that is, the code server B) is the same in your own code. A client and server B will start when his own machine IP registration to the zookeeper, client server ip on A zk will pull on the disk, and what ip record which services (exposed when the server starts to zk), and then the client server-side service calls based on ip.
dubbo necessary to Server B (provider) interface class labeled packet, the server B (the provider) to achieve, client A (consumer) to call.
maven dependent : In a multi-module maven project of inter-dependence maven sub-module implementation calls. For example, module A calling module B, packaged into JAR module B, is introduced into the module A (corresponding modules have module B A), but in reality modules A and B are running on the same project. The dubbo providers and consumers are two separate services (A simply calls B, does not have B).