第一个查询接口

第一个查询接口

Rest服务最先想到的就是查询接口

列表分页查询是每个玩家最常见接口。

• controller 提供接口mapping
• service 提供业务实现
• VO 提供对象数据结构
• 统一返回值
• 分页数据结构
• lombak使用
• fastjson

添加json和lombak依赖

lombok有些特殊除了依赖还需要插件具体参考：

https://www.cnblogs.com/hcgk/p/16916452.html

fastjson暂时用不到

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.83</version>
        </dependency>

统一返回值

一个工程，一个项目甚至一个产品应该统一返回值。

如果每个后台都自己定义一套code，一套返回值数据结构，只能导致产品的混乱。

前后台联调无休止的争吵。

• ResultDataVO
• CommonUtil

package com.wht.test.mapper.vo;
 
import lombok.Data;
 
/**
 * 接口统一返回值对象
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:04:34
 */
@Data
public class ResultDataVO {
    public static final String SUCCESS_CODE = "200";
 
    public static final String FAILED_CODE = "500";
 
    private String code;
 
    private String message;
 
    private Object resultData;
}

package com.wht.test.util;
 
import com.wht.test.mapper.vo.ResultDataVO;
 
/**
 * 基础工具类
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:11:36
 */
public class CommonUtil {
    /**
     * 所有接口统一返回值
     *
     * @param code    编码
     * @param message 提示信息
     * @param data    数据
     * @return 结果
     */
    public static ResultDataVO result(String code, String message, Object data) {
        ResultDataVO resultDataVO = new ResultDataVO();
        resultDataVO.setCode(code);
        resultDataVO.setMessage(message);
        resultDataVO.setResultData(data);
        return resultDataVO;
    }
}

定义分页信息

分页的数据结构也应该统一封装，否则还是混乱

• PageVO
• PageResult

package com.wht.test.mapper.vo.common;
 
/**
 * 分页VO
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:17:52
 */
public class PageVO {
    protected int totalRows;    // 总页数
 
    protected int pageSize;     // 分页大小
 
    protected int curPage;      // 当前页
 
    protected int resultCode;   // 结果类型
 
    protected int orderBy;      // 排序
 
    protected int startIndex;   // 开始位置
 
    protected int endIndex;     // 结束位置
 
    protected int totalPages;   // 总页数
 
    public int getTotalRows() {
        return totalRows;
    }
 
    public void setTotalRows(int totalRows) {
        this.totalRows = totalRows;
    }
 
    public int getPageSize() {
        return pageSize;
    }
 
    public void setPageSize(int pageSize) {
        this.pageSize = pageSize;
    }
 
    public int getCurPage() {
        return curPage < 0 ? 1 : curPage;
    }
 
    public void setCurPage(int curPage) {
        this.curPage = curPage;
    }
 
    public int getResultCode() {
        return resultCode;
    }
 
    public void setResultCode(int resultCode) {
        this.resultCode = resultCode;
    }
 
    public int getOrderBy() {
        return orderBy;
    }
 
    public void setOrderBy(int orderBy) {
        this.orderBy = orderBy;
    }
 
    public int getStartIndex() {
        return (curPage - 1) * pageSize;
    }
 
    public void setStartIndex(int startIndex) {
        this.startIndex = startIndex;
    }
 
    public int getEndIndex() {
        int leveNum = totalRows % pageSize;
        if (leveNum == 0) {
            return curPage * pageSize;
        } else {
            return (curPage - 1) * pageSize + leveNum;
        }
    }
 
    public void setEndIndex(int endIndex) {
        this.endIndex = endIndex;
    }
 
    public int getTotalPages() {
        return this.totalRows % this.pageSize == 0 ? this.totalRows / this.pageSize : this.totalRows / this.pageSize + 1;
    }
 
    public void setTotalPages(int totalPages) {
        this.totalPages = totalPages;
    }
}

package com.wht.test.mapper.vo.common;
 
import lombok.Data;
 
import java.util.List;
 
/**
 * 分页列表VO
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:17:20
 */
@Data
public class PageResult<T> {
    private List<T> result;
    private PageVO pageVO;
}

测试对象数据结构定义

package com.wht.test.mapper.vo.common;
 
import lombok.Data;
 
/**
 * 测试对象
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:28:29
 */
@Data
public class RestTestVO {
    private int id;
 
    private String name;
 
    private String enterpriseId;
}

Get接口开发

• RestTestController控制层定义
• RestTestService业务层实现类实现
• IRestTestService业务层接口定义

package com.wht.test.service;
 
import com.wht.test.mapper.vo.common.PageVO;
import com.wht.test.mapper.vo.common.RestTestVO;
import com.wht.test.mapper.vo.common.ResultDataVO;
 
/**
 * rest接口业务层解耦
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:00:34
 */
public interface IRestTestService {
 
    /**
     *
     * @param restTestVO
     * @param pageVO
     * @return
     */
    ResultDataVO getTestPageList(RestTestVO restTestVO, PageVO pageVO);
}

package com.wht.test.service.impl;
 
import com.wht.test.mapper.vo.common.PageResult;
import com.wht.test.mapper.vo.common.PageVO;
import com.wht.test.mapper.vo.common.RestTestVO;
import com.wht.test.mapper.vo.common.ResultDataVO;
import com.wht.test.service.IRestTestService;
import com.wht.test.util.CommonUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
 
import javax.servlet.http.HttpServletRequest;
import java.util.ArrayList;
import java.util.List;
 
/**
 * rest接口业务层
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 22:01:08
 */
@Service
@Slf4j
public class RestTestService implements IRestTestService {
    @Override
    public ResultDataVO getTestPageList(RestTestVO restTestVO, PageVO pageVO) {
        // 有些项目不喜欢方法中request作为参数传递
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest();
        String userType = request.getHeader("userType");
        log.info("userType={}", userType);
        List<RestTestVO> testVOList = new ArrayList<>();
        // int rows = testDao.getTestPageListCount(restTestVO);
        int rows = 1000;
        if (rows > 0) {
            pageVO.setTotalRows(rows);
//          testVOList = testDao.getTestPageList(restTestVO,pageVO);
            for (int i = 0; i < 10; i++) {
                RestTestVO vo = new RestTestVO();
                vo.setId(i + 1);
                vo.setName("test_" + (i + 1));
                vo.setEnterpriseId(restTestVO.getEnterpriseId());
                testVOList.add(vo);
            }
            PageResult<RestTestVO> pageResult = new PageResult<>();
            pageResult.setResult(testVOList);
            pageResult.setPageVO(pageVO);
            return CommonUtil.result(ResultDataVO.SUCCESS_CODE, "查询成功", pageResult);
        }
        return null;
    }
}

package com.wht.test.controller;
 
import com.wht.test.mapper.vo.common.PageVO;
import com.wht.test.mapper.vo.common.RestTestVO;
import com.wht.test.mapper.vo.common.ResultDataVO;
import com.wht.test.service.IRestTestService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
 
/**
 * rest接口控制层
 *
 * @Author 红尘过客
 * @DateTime 2023-04-24 21:56:52
 */
@RestController
public class RestTestController {
    @Autowired
    private IRestTestService restTestService;
 
    /**
     * 第一个rest分页查询接口模拟
     *
     * @param restTestVO   请求参数
     * @param enterpriseId 企业ID
     * @param pageSize     每页大小
     * @param curPage      当前页
     * @return 查询结果
     */
    @RequestMapping(value = "enterprises/{enterprise_id}/rest/test/{pageSize}/{curPage}", method = RequestMethod.GET)
    ResultDataVO getTestPageList(RestTestVO restTestVO, @PathVariable(value = "enterprise_id") String enterpriseId,
                                 @PathVariable(value = "pageSize") int pageSize, @PathVariable(value = "curPage") int curPage) {
        restTestVO.setEnterpriseId(enterpriseId);
        PageVO pageVO = new PageVO();
        pageVO.setCurPage(curPage);
        pageVO.setPageSize(pageSize);
        return restTestService.getTestPageList(restTestVO, pageVO);
    }
 
}

启动用谷歌浏览器插件验证下

• 学习路径参数
• 统一返回值
• 分页信息封装方法
• 预留dao层调用

请求地址：

http://localhost:8080/enterprises/alibaba/rest/test/20/1

返回值：

{
    "code": "200",
    "message": "查询成功",
    "resultData": {
        "result": [
            {
                "id": 1,
                "name": "test_1",
                "enterpriseId": "alibaba"
            },
            {
                "id": 2,
                "name": "test_2",
                "enterpriseId": "alibaba"
            },
            {
                "id": 3,
                "name": "test_3",
                "enterpriseId": "alibaba"
            },
            {
                "id": 4,
                "name": "test_4",
                "enterpriseId": "alibaba"
            },
            {
                "id": 5,
                "name": "test_5",
                "enterpriseId": "alibaba"
            },
            {
                "id": 6,
                "name": "test_6",
                "enterpriseId": "alibaba"
            },
            {
                "id": 7,
                "name": "test_7",
                "enterpriseId": "alibaba"
            },
            {
                "id": 8,
                "name": "test_8",
                "enterpriseId": "alibaba"
            },
            {
                "id": 9,
                "name": "test_9",
                "enterpriseId": "alibaba"
            },
            {
                "id": 10,
                "name": "test_10",
                "enterpriseId": "alibaba"
            }
        ],
        "pageVO": {
            "totalRows": 1000,
            "pageSize": 20,
            "curPage": 1,
            "resultCode": 0,
            "orderBy": 0,
            "startIndex": 0,
            "endIndex": 20,
            "totalPages": 50
        }
    }
}