Generate Java Source Files Manually

```
$ cd $PROJECT_ROOT/src/main/proto/
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/example/*.proto

$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/model_management.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/predict.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/model.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/regression.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/classification.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/inference.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/get_model_metadata.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/input.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/apis/get_model_status.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/config/model_server_config.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/config/logging_config.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/config/log_collector_config.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/util/status.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow_serving/sources/storage_path/file_system_storage_path_source.proto

$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/named_tensor.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/saver.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/meta_graph.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/config.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/debug.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/rewriter_config.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/protobuf/cluster.proto

$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/lib/core/error_codes.proto

$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/allocation_description.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/tensor_description.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/cost_graph.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/graph.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/op_def.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/node_def.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/function.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/versions.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/tensor.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/tensor_shape.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/types.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/resource_handle.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/attr_value.proto
$ protoc --java_out $PROJECT_ROOT/src/main/java --proto_path ./ ./tensorflow/core/framework/step_stats.proto

# the following 3 cmds will generate extra *Grpc.java stub source files in addition to the regular protobuf Java source files.
# The output grpc-java files are put in the same directory as the regular java source files.
# note the --plugin option uses the grpc-java plugin file we created in step 1.
$ protoc --grpc-java_out $PROJECT_ROOT/src/main/java --java_out $PROJECT_ROOT/src/main/java --proto_path ./ tensorflow_serving/apis/prediction_service.proto --plugin=protoc-gen-grpc-java=$SRC/grpc-java/compiler/build/exe/java_plugin/protoc-gen-grpc-java
$ protoc --grpc-java_out $PROJECT_ROOT/src/main/java --java_out $PROJECT_ROOT/src/main/java --proto_path ./ tensorflow_serving/apis/model_service.proto --plugin=protoc-gen-grpc-java=$SRC/grpc-java/compiler/build/exe/java_plugin/protoc-gen-grpc-java
$ protoc --grpc-java_out $PROJECT_ROOT/src/main/java --java_out $PROJECT_ROOT/src/main/java --proto_path ./ tensorflow_serving/apis/session_service.proto --plugin=protoc-gen-grpc-java=$SRC/grpc-java/compiler/build/exe/java_plugin/protoc-gen-grpc-java