java-protobuf

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Google protocal buffer.

How to use

  1. Designing objects

  2. Describing objects

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    package tutorial;
    option java_package = "com.example.tutorial";
    option java_outer_classname = "AddressBookProtos";
    message Person {
      required string name = 1;
      required int32 id = 2;
      optional string email = 3;
      enum PhotoType {
        MOBILE = 0;
        HOME = 1;
        WORK = 2;
      }
      message PhoneNumber {
        required string number = 1;
        optional PhotoType type = 2 [default = HOME];
      }
      required PhoneNumber phone = 4;
    }
    message AddressBook {
      repeated  Person person = 1;
    }

  3. Compiling the description

  4. Obtaining the generated source-code
    $> protoc --java_out=$DST_DIR addressbook.proto
  5. Importing objects into your project
    Import package com.example.tutorial.
    Add protobuf-java-2.6.1.jar to build path.

  6. Instantiating objects

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    PhoneNumber number = PhoneNumber.newBuilder()
        .setNumber("12345678")
        .setType(PhotoType.MOBILE)
        .build();
    Person p = Person.newBuilder()
        .setName("tom")
        .setId(100)
        .setEmail("abc@hotmail.com")
        .addPhone(number)
        .build();

  7. Using objects

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    // serialize.
    FileOutputStream fos1 = new FileOutputStream("TestSePB.dat");
    long start = System.nanoTime();
    p.writeTo(fos1);
    System.out.println("" + (System.nanoTime() - start));
    fos1.close();
    // deserialize.
    Person pp = Person.parseFrom(new FileInputStream("TestSePB.dat"));

Full code can be found on github