集成grpc，普通對象與grpc對象轉換

集成grpc，普通對象與grpc對象轉換

分佈式開發涉及到遠程過程調用即RPC。須要集成grpc。但若是想無縫集成，則涉及到普通的請求對象轉換爲grpc請求對象。
因爲null不能序列化，因此grpc的對象屬性都會有默認值，這在開發中，很難區分，到底請求傳的是默認值仍是請求自己攜帶的值。因此使用protocol buffers 的oneof關鍵字，用於規避默認值。
新建員工類

package com.dld.hll.financial;

import java.math.BigDecimal;
import java.sql.Date;
import java.sql.Timestamp;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * @Author yue chao
 * @Date 2019/8/10 0010 下午 21:23
 */

public class EmpOne {
    private Long empIdOne;

    private String empNameOne;

    private Boolean empSexOne;

    private Long totalAssetOne;

    private List<String> skills;

    private Set<Integer> lucks;

    private Map<String, String> relations;

    private Date bornDate;

    private Timestamp createTime;

    private BigDecimal salary;
    
    private DeptOne dept;

    // ... 省略 get set
}

新建部門類

package com.dld.hll.financial;

/**
 * @Author yue chao
 * @Date 2019/8/10 0010 下午 21:24
 */

public class DeptOne {

    private Long deptIdOne;

    private String deptNameOne;

    private Byte deptTypeOne;
    // 省略 get set 
}

proto文件

syntax = "proto3";
option java_multiple_files = true;
option java_package = "com.dld.hll.financial.grpc";
option java_outer_classname = "EmpProto";

message EmpOne {
    oneof oneof_empId {
        int64 empIdOne = 4;
    }
    oneof oneof_totalAssetOne {
        int64 totalAssetOne = 8;
    }
    oneof oneof_empName {
        string empNameOne = 5;
    }
    oneof oneof_empSex {
        bool empSexOne = 6;
    }
    DeptOne dept = 7;
    repeated string skills = 9;
    repeated int32 lucks = 10;
    map<string, string> relations = 11;
    oneof oneof_bornDate {
        string bornDate = 12;
    }
    oneof oneof_createTime {
        string createTime = 13;
    }
    oneof oneof_salary {
        string salary = 14;
    }
}

message DeptOne {
    oneof oneof_deptId {
        int32 deptIdOne = 4;
    }
    oneof oneof_deptName {
        string deptNameOne = 5;
    }
    oneof oneof_deptType {
        int32 deptTypeOne = 6;
    }
}

單元測試代碼

package com.dld.hll.financial;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.protobuf.util.JsonFormat;
import org.apache.commons.lang3.StringUtils;
import org.junit.Test;

import java.io.IOException;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

/**
 * @Author yue chao
 * @Date 2019/8/12 0012 上午 11:40
 */
public class EmpOneTest {

    /**
     * oneof  普通請求轉grpc請求，再轉普通請求
     * @throws IOException
     */
    @Test
    public void testOneCommonRequestTransformToGrpcRequest() throws IOException {
        oneCommonRequestTransformToGrpcRequest();
    }

    public static void oneCommonRequestTransformToGrpcRequest() throws IOException {
        DeptOne dept = new DeptOne();
        dept.setDeptIdOne(0L);
        dept.setDeptNameOne(StringUtils.EMPTY);
        dept.setDeptTypeOne((byte)0);

        List<String> skills = new ArrayList<>();
        skills.add("EDVSD");

        Set<Integer> lucks = new HashSet<>();

        EmpOne emp = new EmpOne();
        emp.setEmpIdOne(0L);
        emp.setEmpNameOne(StringUtils.EMPTY);
        emp.setEmpSexOne(false);
        emp.setDept(dept);

        emp.setSkills(skills);
        emp.setLucks(lucks);
        emp.setBornDate(new java.sql.Date(System.currentTimeMillis()));
        emp.setCreateTime(new java.sql.Timestamp(System.currentTimeMillis()));
        emp.setSalary(new BigDecimal("22.33"));

        Gson gson = new GsonBuilder().serializeNulls()
                .setPrettyPrinting()
                .registerTypeAdapter(java.sql.Timestamp.class, new TimeStampGSON())
                .registerTypeAdapter(java.sql.Date.class, new SqlDateGSON())
                .create();
        String empJson = gson.toJson(emp);
        System.out.println("普通對象json==============");
        System.out.println(empJson);

        com.dld.hll.financial.grpc.EmpOne.Builder builder = com.dld.hll.financial.grpc.EmpOne.newBuilder();

        JsonFormat.parser().merge(empJson, builder);
        com.dld.hll.financial.grpc.EmpOne empOneGrpc = builder.build();

        StringBuilder sb = new StringBuilder();
        JsonFormat.printer()
                .includingDefaultValueFields() // 設置採用默認值，當集合爲空的時候會使用[]表示，map爲空的時候採用{}，這樣可能有效防止直接使用而遇到的空指針
                .appendTo(empOneGrpc, sb);
        System.out.println("grpc對象Json==============");
        // 能夠觀察到普通對象json與grpcJson的區別，grpcJson對象字段爲null的字段不顯示,集合或map爲空，則使用以上規則處理了
        System.out.println(sb);

        Gson gson2 = new GsonBuilder()
                .setPrettyPrinting()
                .serializeNulls()
                .registerTypeAdapter(java.sql.Timestamp.class, new TimeStampGSON())
                .registerTypeAdapter(java.sql.Date.class, new SqlDateGSON())
                .create();
        EmpOne vo = gson2.fromJson(sb.toString(), EmpOne.class);

        System.out.println("普通對象json==============");
        System.out.println(gson2.toJson(vo));
    }
}

測試結果

普通對象json==============
{
  "empIdOne": 0,
  "empNameOne": "",
  "empSexOne": false,
  "totalAssetOne": null,
  "skills": [
    "EDVSD"
  ],
  "lucks": [],
  "relations": null,
  "bornDate": "2019-08-12",
  "createTime": "2019-08-12 13:39:14",
  "salary": 22.33,
  "dept": {
    "deptIdOne": 0,
    "deptNameOne": "",
    "deptTypeOne": 0
  }
}
grpc對象Json==============
{
  "empIdOne": "0",
  "empNameOne": "",
  "empSexOne": false,
  "dept": {
    "deptIdOne": 0,
    "deptNameOne": "",
    "deptTypeOne": 0
  },
  "skills": ["EDVSD"],
  "lucks": [],
  "relations": {
  },
  "bornDate": "2019-08-12",
  "createTime": "2019-08-12 13:39:14",
  "salary": "22.33"
}
普通對象json==============
{
  "empIdOne": 0,
  "empNameOne": "",
  "empSexOne": false,
  "totalAssetOne": null,
  "skills": [
    "EDVSD"
  ],
  "lucks": [],
  "relations": {},
  "bornDate": "2019-08-12",
  "createTime": "2019-08-12 13:39:14",
  "salary": 22.33,
  "dept": {
    "deptIdOne": 0,
    "deptNameOne": "",
    "deptTypeOne": 0
  }
}