@SuppressWarnings({"rawtypes"})
  @java.lang.Override
  protected com.google.protobuf.MapFieldReflectionAccessor internalGetMapFieldReflection(
      int number) {
    switch (number) {
      case 4:
        return internalGetLabels();
      default:
        throw new RuntimeException("Invalid map field number: " + number);
    }
  }
<pre>
Source message describes a specific vm migration Source resource. It contains
the source environment information.
</pre>

Protobuf type {@code google.cloud.vmmigration.v1.Source}
java-vmmigration/proto-google-cloud-vmmigration-v1/src/main/java/com/google/cloud/vmmigration/v1/Source.java