基于Protobuf動(dòng)態(tài)解析在Java中的應(yīng)用 包含例子程序

option java_package="com.liulei.cinema";

enum MovieType{
 CHILDREN=1;
 ADULT=2;
 NORMAL=3;
 OHTER=4;
}

enum Gender{
 MAN=1;
 WOMAN=2;
 OTHER=3;
}

message Movie{
 required string name=1;
 required MovieType type=2;
 optional int32 releaseTimeStamp=3;
 optional string description=4;
}

message Customer{
 required string name=1;
 optional Gender gender=2;
 optional int32 birthdayTimeStamp=3;
}

message Ticket{
 required int32 id=1;
 required Movie movie=2;
 required Customer customer=3;
}

public static void main( String[] args ) {

  Cinema.Movie.Builder movieBuilder = Cinema.Movie.newBuilder();
  movieBuilder.setName("The Shining");
  movieBuilder.setType(Cinema.MovieType.ADULT);
  movieBuilder.setReleaseTimeStamp(327859200);

  System.out.println("Dynamic Message Parse by proto file");
  try {
   byte[] buffer3 = new byte[movieBuilder.build().getSerializedSize()];
   CodedOutputStream codedOutputStream3 = CodedOutputStream.newInstance(buffer3);
   try {
    movieBuilder.build().writeTo(codedOutputStream3);
    System.out.println(buffer3);
   } catch (IOException e) {
    e.printStackTrace();
   }
   String protocCMD = "protoc --descriptor_set_out=cinema.description ./cinema.proto --proto_path=.";
   Process process = Runtime.getRuntime().exec(protocCMD);
   process.waitFor();
   int exitValue = process.exitValue();
   if (exitValue != 0) {
    System.out.println("protoc execute failed");
    return;
   }
   Descriptors.Descriptor pbDescritpor = null;
   DescriptorProtos.FileDescriptorSet descriptorSet = DescriptorProtos.FileDescriptorSet.parseFrom(new FileInputStream("./cinema.description"));
   for (DescriptorProtos.FileDescriptorProto fdp : descriptorSet.getFileList()) {
    Descriptors.FileDescriptor fileDescriptor = Descriptors.FileDescriptor.buildFrom(fdp, new Descriptors.FileDescriptor[]{});
    for (Descriptors.Descriptor descriptor : fileDescriptor.getMessageTypes()) {
     if (descriptor.getName().equals("Movie")) {
      System.out.println("Movie descriptor found");
      pbDescritpor = descriptor;
      break;
     }
    }
   }
   if (pbDescritpor == null) {
    System.out.println("No matched descriptor");
    return;
   }
   DynamicMessage.Builder pbBuilder = DynamicMessage.newBuilder(pbDescritpor);

   Message pbMessage = pbBuilder.mergeFrom(buffer3).build();
   System.out.println(pbMessage);

  } catch (Exception e) {
   System.out.println("Exception");
   e.printStackTrace();
  }
 }