Update Protobuf

doc/source/utils/protobuf/protobufJava.md

@@ -0,0 +1,12 @@
+# Protobuf Java
+
+>Protocol buffers are a language-neutral, platform-neutral extensible mechanism for serializing structured data.
+
+## Results
+- `ProtobufJavaTest`
+- `AddressBookTest`
+
+## References
+- [Protocol Buffers](https://developers.google.cn/protocol-buffers?hl=zh-cn)
+- [Protocol Buffer Basics: Java](https://developers.google.cn/protocol-buffers/docs/javatutorial?hl=zh-cn)
+- [How to use Google Protocol Buffers in Java to serialize structured Data](https://roytuts.com/how-to-use-google-protocol-buffers-in-java-to-serialize-structured-data/)

doc/source/utils/protobuf/protobufLanguageGuide.md

@@ -0,0 +1,31 @@
+# Protobuf Language Guide
+
+## Scalar Value Types
+
+.proto Type | C++ Type | Java/Kotlin Type | Python Type | Go Type | Ruby Type | C# Type | PHP Type | Dart Type
+---|---|---|---|---|---|---|---|---
+double | double | double | float | float64 | Float | double | float | double
+float | float | float | float | float32 | Float | float | float | double
+int32 | int32 | int | int | int32 | Fixnum or Bignum (as required) | int | integer | int
+int64 | int64 | long | int/long | int64 | Bignum | long | integer/string | Int64
+uint32 | uint32 | int | int/long | uint32 | Fixnum or Bignum (as required) | uint | integer | int
+uint64 | uint64 | long | int/long | uint64 | Bignum | ulong | integer/string | Int64
+sint32 | int32 | int | int | int32 | Fixnum or Bignum (as required) | int | integer | int
+sint64 | int64 | long | int/long | int64 | Bignum | long | integer/string | Int64
+fixed32 | uint32 | int | int/long | uint32 | Fixnum or Bignum (as required) | uint | integer | int
+fixed64 | uint64 | long | int/long | uint64 | Bignum | ulong | integer/string | Int64
+sfixed32 | int64 | long | int/long | int64 | Bignum | long | integer/string | Int64
+bool | bool | boolean | bool | bool | TrueClass/FalseClass | bool | boolean | bool
+string | string | String | str/unicode | string | String (UTF-8) | string | string | String
+bytes | string | ByteString | str | []byte | String (ASCII-8BIT) | ByteString | string | List
+
+## Default Values
+- For strings, the default value is the empty string.
+- For bytes, the default value is empty bytes.
+- For bools, the default value is false.
+- For numeric types, the default value is zero.
+- For [enums](https://developers.google.cn/protocol-buffers/docs/proto3?hl=zh-cn#enum), the default value is the **first defined enum value**, which must be 0.
+- For message fields, the field is not set. Its exact value is language-dependent. See the [generated code guide](https://developers.google.cn/protocol-buffers/docs/reference/overview?hl=zh-cn) for details.
+
+## References
+- [Language Guide (proto3)](https://developers.google.cn/protocol-buffers/docs/proto3?hl=zh-cn)

utils/src/main/java/t5750/utils/protobuf/AddressBookTest.java

@@ -0,0 +1,18 @@
+package t5750.utils.protobuf;
+
+import t5750.utils.util.Global;
+
+public class AddressBookTest {
+	public static void main(String[] args) {
+		Person person = Person.newBuilder().setId(1234)
+				.setName(Global.T5750.toUpperCase())
+				.setEmail(Global.T5750 + "@example.com")
+				.addPhones(Person.PhoneNumber.newBuilder().setNumber("555-4321")
+						.setType(Person.PhoneType.HOME))
+				.build();
+		System.out.println(person.getId());
+		System.out.println(person.getName());
+		System.out.println(person.getEmail());
+		System.out.println(person.getPhonesList().get(0));
+	}
+}

utils/src/main/resources/protoc/addressbook.proto

@@ -0,0 +1,30 @@
+syntax = "proto2";
+
+package tutorial;
+
+option java_multiple_files = true;
+option java_package = "t5750.utils.protobuf";
+option java_outer_classname = "AddressBookProtos";
+
+message Person {
+  optional string name = 1;
+  optional int32 id = 2;
+  optional string email = 3;
+
+  enum PhoneType {
+    MOBILE = 0;
+    HOME = 1;
+    WORK = 2;
+  }
+
+  message PhoneNumber {
+    optional string number = 1;
+    optional PhoneType type = 2 [default = HOME];
+  }
+
+  repeated PhoneNumber phones = 4;
+}
+
+message AddressBook {
+  repeated Person people = 1;
+}