MyBatis一对多查询三表三层查询
首先，将数据表列出
第一张表INDICATIONSYSTEM表（可以简单记住system表），主要用到数据为标红区数据
第二张表INDICATION表（可以简单记住indication表），主要用到数据为标红区数据
第三张表INDICATIONVALUE表（可以简单记住value表），主要用到数据为标红区数据
三张表的对应关系为：
传入参数为system表中PID值，system表中ID对应indication表中INDICATIONSYSTEMIDS字段，查询indication表中ID，对应value表中INDICATIONID字段
实体层文件
Indiactionsystem.java
package zbinfo.model;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.mybatis.spring.annotation.MapperScan;
import java.io.Serializable;
import java.util.List;
@MapperScan
@JsonInclude(JsonInclude.Include.NON_NULL)
public class Indicationsystem implements Serializable {
@JsonProperty("id")
private Long ID;
@JsonProperty("name")
private String NAME;
@JsonProperty("pid")
private Long PID;
@JsonProperty("description")
private String DESCRIPTION;
@JsonProperty("children")
private List INDICATION;
private static final long serialVersionUID = 1L;
@JsonIgnore
public Long getID() {
return ID;
}
@JsonIgnore
public void setID(Long ID) {
this.ID = ID;
}
@JsonIgnore
public String getNAME() {
return NAME;
}
@JsonIgnore
public void setNAME(String NAME) {
this.NAME = NAME == null ? null : NAME.trim();
}
@JsonIgnore
public Long getPID() {
return PID;
}
@JsonIgnore
public void setPID(Long PID) {
this.PID = PID;
}
@JsonIgnore
public String getDESCRIPTION() {
return DESCRIPTION;
}
@JsonIgnore
public void setDESCRIPTION(String DESCRIPTION) {
this.DESCRIPTION = DESCRIPTION == null ? null : DESCRIPTION.trim();
}
@JsonIgnore
public List getINDICATION() {
return INDICATION;
}
@JsonIgnore
public void setINDICATION(List INDICATION) {
this.INDICATION = INDICATION;
}
} Indication.java
package zbinfo.model;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.mybatis.spring.annotation.MapperScan;
import java.io.Serializable;
import java.util.Date;
import java.util.List;
@MapperScan
@JsonInclude(JsonInclude.Include.NON_NULL)
public class Indication implements Serializable {
@JsonProperty("id")
private Long ID;
@JsonProperty("name")
private String NAME;
@JsonProperty("range")
private String RANGE;
@JsonProperty("cycle")
private String CYCLE;
@JsonProperty("category")
private String CATEGORY;
@JsonProperty("source")
private String SOURCE;
@JsonProperty("dimention")
private Long DIMENTION;
@JsonProperty("indicationsystemids")
private int[] INDICATIONSYSTEMIDS;
@JsonProperty("patternids")
private int[] PATTERNIDS;
@JsonProperty("correlation")
private String CORRELATION;
@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonProperty("limit")
private String LIMIT;
@JsonProperty("creationtime")
private Date CREATIONTIME;
@JsonProperty("areas")
private List INDICATIONVALUE;
@JsonProperty("meaning")
private String MEANING;
@JsonProperty("organization")
private String ORGANIZATION;
private static final long serialVersionUID = 1L;
@JsonIgnore
public Long getID() {
return ID;
}
@JsonIgnore
public void setID(Long ID) {
this.ID = ID;
}
@JsonIgnore
public String getNAME() {
return NAME;
}
@JsonIgnore
public void setNAME(String NAME) {
this.NAME = NAME == null ? null : NAME.trim();
}
@JsonIgnore
public String getRANGE() {
return RANGE;
}
@JsonIgnore
public void setRANGE(String RANGE) {
this.RANGE = RANGE == null ? null : RANGE.trim();
}
@JsonIgnore
public String getCYCLE() {
return CYCLE;
}
@JsonIgnore
public void setCYCLE(String CYCLE) {
this.CYCLE = CYCLE == null ? null : CYCLE.trim();
}
@JsonIgnore
public String getCATEGORY() {
return CATEGORY;
}
@JsonIgnore
public void setCATEGORY(String CATEGORY) {
this.CATEGORY = CATEGORY == null ? null : CATEGORY.trim();
}
@JsonIgnore
public String getSOURCE() {
return SOURCE;
}
@JsonIgnore
public void setSOURCE(String SOURCE) {
this.SOURCE = SOURCE == null ? null : SOURCE.trim();
}
@JsonIgnore
public Long getDIMENTION() {
return DIMENTION;
}
@JsonIgnore
public void setDIMENTION(Long DIMENTION) {
this.DIMENTION = DIMENTION;
}
@JsonIgnore
public int[] getINDICATIONSYSTEMIDS() {
return INDICATIONSYSTEMIDS;
}
@JsonIgnore
public void setINDICATIONSYSTEMIDS(int[] INDICATIONSYSTEMIDS) {
this.INDICATIONSYSTEMIDS = INDICATIONSYSTEMIDS == null ? null : INDICATIONSYSTEMIDS;
}
@JsonIgnore
public int[] getPATTERNIDS() {
return PATTERNIDS;
}
@JsonIgnore
public void setPATTERNIDS(int[] PATTERNIDS) {
this.PATTERNIDS = PATTERNIDS == null ? null : PATTERNIDS;
}
@JsonIgnore
public String getCORRELATION() {
return CORRELATION;
}
@JsonIgnore
public void setCORRELATION(String CORRELATION) {
this.CORRELATION = CORRELATION == null ? null : CORRELATION.trim();
}
@JsonIgnore
public String getLIMIT() {
return LIMIT;
}
@JsonIgnore
public void setLIMIT(String LIMIT) {
this.LIMIT = LIMIT == null ? null : LIMIT.trim();
}
@JsonIgnore
public Date getCREATIONTIME() {
return CREATIONTIME;
}
@JsonIgnore
public void setCREATIONTIME(Date CREATIONTIME) {
this.CREATIONTIME = CREATIONTIME;
}
@JsonIgnore
public List getINDICATIONVALUE() {
return INDICATIONVALUE;
}
@JsonIgnore
public void setINDICATIONVALUE(List INDICATIONVALUE) {
this.INDICATIONVALUE = INDICATIONVALUE;
}
@JsonIgnore
public String getMEANING() {
return MEANING;
}
@JsonIgnore
public void setMEANING(String MEANING) {
this.MEANING = MEANING;
}
@JsonIgnore
public String getORGANIZATION() {
return ORGANIZATION;
}
@JsonIgnore
public void setORGANIZATION(String ORGANIZATION) {
this.ORGANIZATION = ORGANIZATION;
}
} Indicationvalue.java
package zbinfo.model;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.mybatis.spring.annotation.MapperScan;
import java.io.Serializable;
import java.math.BigDecimal;
@MapperScan
@JsonInclude(JsonInclude.Include.NON_NULL)
public class Indicationvalue implements Serializable {
@JsonProperty("id")
private Long ID;
@JsonProperty("indicationid")
private Long INDICATIONID;
@JsonProperty("year")
private Long YEAR;
@JsonProperty("areacode")
private String AREACODE;
@JsonProperty("areaname")
private String AREANAME;
@JsonProperty("targetvalue")
private String TARGETVALUE;
@JsonProperty("actuallyvalue")
private String ACTUALLYVALUE;
@JsonProperty("unit")
private String UNIT;
@JsonProperty("threshold")
private BigDecimal THRESHOLD;
@JsonProperty("floatvalue")
private BigDecimal FLOATVALUE;
@JsonProperty("warningcolor")
private String WARNINGCOLOR;
@JsonProperty("weight")
private BigDecimal WEIGHT;
@JsonProperty("map_url")
private String URL;
@JsonProperty("sumActuallyValue")
private Long SUMACTUALLY;
@JsonProperty("sumTargetValue")
private Long SUMTARGET;
private static final long serialVersionUID = 1L;
@JsonIgnore
public Long getID() {
return ID;
}
@JsonIgnore
public void setID(Long ID) {
this.ID = ID;
}
@JsonIgnore
public Long getINDICATIONID() {
return INDICATIONID;
}
@JsonIgnore
public void setINDICATIONID(Long INDICATIONID) {
this.INDICATIONID = INDICATIONID;
}
@JsonIgnore
public Long getYEAR() {
return YEAR;
}
@JsonIgnore
public void setYEAR(Long YEAR) {
this.YEAR = YEAR;
}
@JsonIgnore
public String getAREACODE() {
return AREACODE;
}
@JsonIgnore
public void setAREACODE(String AREACODE) {
this.AREACODE = AREACODE == null ? null : AREACODE.trim();
}
@JsonIgnore
public String getAREANAME() {
return AREANAME;
}
@JsonIgnore
public void setAREANAME(String AREANAME) {
this.AREANAME = AREANAME == null ? null : AREANAME.trim();
}
@JsonIgnore
public String getTARGETVALUE() {
return TARGETVALUE;
}
@JsonIgnore
public void setTARGETVALUE(String TARGETVALUE) {
this.TARGETVALUE = TARGETVALUE;
}
@JsonIgnore
public String getACTUALLYVALUE() {
return ACTUALLYVALUE;
}
@JsonIgnore
public void setACTUALLYVALUE(String ACTUALLYVALUE) {
this.ACTUALLYVALUE = ACTUALLYVALUE;
}
@JsonIgnore
public String getUNIT() {
return UNIT;
}
@JsonIgnore
public void setUNIT(String UNIT) {
this.UNIT = UNIT == null ? null : UNIT.trim();
}
@JsonIgnore
public BigDecimal getTHRESHOLD() {
return THRESHOLD;
}
@JsonIgnore
public void setTHRESHOLD(BigDecimal THRESHOLD) {
this.THRESHOLD = THRESHOLD;
}
@JsonIgnore
public BigDecimal getFLOATVALUE() {
return FLOATVALUE;
}
@JsonIgnore
public void setFLOATVALUE(BigDecimal FLOATVALUE) {
this.FLOATVALUE = FLOATVALUE;
}
@JsonIgnore
public String getWARNINGCOLOR() {
return WARNINGCOLOR;
}
@JsonIgnore
public void setWARNINGCOLOR(String WARNINGCOLOR) {
this.WARNINGCOLOR = WARNINGCOLOR == null ? null : WARNINGCOLOR.trim();
}
@JsonIgnore
public BigDecimal getWEIGHT() {
return WEIGHT;
}
@JsonIgnore
public void setWEIGHT(BigDecimal WEIGHT) {
this.WEIGHT = WEIGHT;
}
@JsonIgnore
public String getURL() {
return URL;
}
@JsonIgnore
public void setURL(String URL) {
this.URL = URL;
}
@JsonIgnore
public Long getSUMACTUALLY() {
return SUMACTUALLY;
}
@JsonIgnore
public void setSUMACTUALLY(Long SUMACTUALLY) {
this.SUMACTUALLY = SUMACTUALLY;
}
@JsonIgnore
public Long getSUMTARGET() {
return SUMTARGET;
}
@JsonIgnore
public void setSUMTARGET(Long SUMTARGET) {
this.SUMTARGET = SUMTARGET;
}
}其中
@JsonInclude(JsonInclude.Include.NON_NULL)作用为搜索中无搜索字段，搜索结果对该字段返回null，去除这些结果为null的字段
@JsonProperty("areaname")作用为返回结果中显示{字段：值}，其中字段的显示名称
IndicationOverview.java实体层
（本文因为项目中多次用到指标总览查询，故新建了IndicationOverview.java文件，该文件可以整合到Indicationsystem.java实体层文件中）
package zbinfo.model;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.mybatis.spring.annotation.MapperScan;
import java.util.List;
/**
* @program: ZBSERVICE
* @description: 多级监测数据查询，如自然资源本底-耕地-耕地现状-耕地现状面积
* @author: Mr.Li
* @create: 2019-08-19
**/
@MapperScan
public class IndicationOverview {
@JsonProperty("id")
private int ID;
@JsonProperty("name")
private String NAME;
@JsonProperty("pid")
private int PID;
@JsonProperty("areaname")
private String AREANAME;
@JsonProperty("year")
private int YEAR;
@JsonProperty("warningcolor")
private String WARNINGCOLOR;
@JsonProperty("children")
private List INDICATION;
@JsonProperty
private List INDICATIONOVERVIEW;
@JsonIgnore
public int getID() {
return ID;
}
@JsonIgnore
public void setID(int ID) {
this.ID = ID;
}
@JsonIgnore
public String getNAME() {
return NAME;
}
@JsonIgnore
public void setNAME(String NAME) {
this.NAME = NAME;
}
@JsonIgnore
public int getPID() {
return PID;
}
@JsonIgnore
public void setPID(int PID) {
this.PID = PID;
}
@JsonIgnore
public String getAREANAME() {
return AREANAME;
}
@JsonIgnore
public void setAREANAME(String AREANAME) {
this.AREANAME = AREANAME;
}
@JsonIgnore
public int getYEAR() {
return YEAR;
}
@JsonIgnore
public void setYEAR(int YEAR) {
this.YEAR = YEAR;
}
@JsonIgnore
public String getWARNINGCOLOR() {
return WARNINGCOLOR;
}
@JsonIgnore
public void setWARNINGCOLOR(String WARNINGCOLOR) {
this.WARNINGCOLOR = WARNINGCOLOR;
}
@JsonIgnore
public List getINDICATION() {
return INDICATION;
}
@JsonIgnore
public void setINDICATION(List INDICATION_OVERVIEW) {
this.INDICATION = INDICATION_OVERVIEW;
}
@JsonIgnore
public List getINDICATIONOVERVIEW() {
return INDICATIONOVERVIEW;
}
@JsonIgnore
public void setINDICATIONOVERVIEW(List INDICATIONOVERVIEW) {
this.INDICATIONOVERVIEW = INDICATIONOVERVIEW;
}
}
mapper文件三种写法
mapper文件（第一种写法）
IndicationsystemMapper.xml
其中
类型均为java.util.HashMap
这么写的好处是在resultmap中写了哪些字段，结果输出时只输出哪些字段（即使实体层中没有@JsonInclude(JsonInclude.Include.NON_NULL)注解，也是只输出这些字段）
注意：
该种写法中，sql语句采用一次查询，一次访问数据库的写法
sql语句中避免各表字段重复，将需要查询字段使用as重新定义字段
接口文件
IndicationsystemMapper.java
package zbinfo.dao;
import org.apache.ibatis.annotations.Mapper;
import zbinfo.model.IndicationOverview;
import java.util.List;
@Mapper
public interface IndicationOverviewMapper {
/*通过PID查询，从第三级指标开始查询*/
List SelectByPID(Object jsonObject);
}
Controller文件
IndicationOverviewController.java
package zbinfo.controller;
import net.sf.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import zbinfo.dao.IndicationOverviewMapper;
import zbinfo.model.Indication;
import zbinfo.model.IndicationOverview;
import zbinfo.model.Indicationvalue;
import java.util.List;
/**
* @program: ZBSERVICE
* @description: 各个指标监测数据展示
* @author: Mr.Li
* @create: 2019-08-20
**/
@RestController
@RequestMapping(value="IndicationOverview")
public class IndicationOverviewController {
@Autowired
IndicationOverviewMapper overViewMapper;
private static final Logger logger = LoggerFactory.getLogger(IndicationOverviewController.class);
@RequestMapping(value="/SelectByPID",method= RequestMethod.POST)
public List SelectByPID(
//@PathVariable(name = "PID", required = true) Integer PID
@RequestBody JSONObject jsonObject
){
logger.debug("开始进行指标总览查询");
logger.debug("查询方法：SelectIndicationOverview，参数：jsonObject=%S",jsonObject);
try
{
List lstOverview = overViewMapper.SelectByPID(jsonObject);
logger.debug("指标总览查询结束，查询成功");
return lstOverview;
}
catch (Exception e)
{
logger.error(e.getMessage());
logger.debug("指标总览查询操作结束，查询失败");
return null;
}
}
} 如果没有配置日志文件，可以将logger相关的语句注释掉；
也可以将try{}catch（）{}语句注释掉
package zbinfo.controller;
import net.sf.json.JSONObject;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import zbinfo.dao.IndicationOverviewMapper;
import zbinfo.model.IndicationOverview;
import java.util.List;
/**
* @program: ZBSERVICE
* @description: 各个指标监测数据展示
* @author: Mr.Li
* @create: 2019-08-20
**/
@RestController
@RequestMapping(value="IndicationOverview")
public class IndicationOverviewController {
@Autowired
IndicationOverviewMapper overViewMapper;
@RequestMapping(value="/SelectByPID",method= RequestMethod.POST)
public List SelectByPID(
//@PathVariable(name = "PID", required = true) Integer PID
@RequestBody JSONObject jsonObject
){
List lstOverview = overViewMapper.SelectByPID(jsonObject);
return lstOverview;
}
} 在postman中调试
结果：
由于结果类型使用java.util.HashMap，没有引用实体层文件，实体层@JsonProperty注解没有起作用（请看下面注意）
最终结果直接将sql语句搜索结果匹配mapresult中规定字段；
[
{
"INDICATIONIDS": 1,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATIONVALUEID": 1,
"INDICATION": {
"INDICATIONIDS": 1,
"INDICATIONVALUE": {
"UNIT": "公顷",
"YEAR": 2010,
"INDICATIONID": 1,
"AREANAME": "福田区",
"ACTUALLYVALUE": "12345",
"INDICATIONVALUEID": 1
},
"INDICATIONNAME": "耕地现状面积",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 1,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATIONVALUEID": 2,
"INDICATION": {
"INDICATIONIDS": 1,
"INDICATIONVALUE": {
"UNIT": "公顷",
"YEAR": 2011,
"INDICATIONID": 1,
"AREANAME": "福田区",
"ACTUALLYVALUE": "12345",
"INDICATIONVALUEID": 2
},
"INDICATIONNAME": "耕地现状面积",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 1,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATIONVALUEID": 23,
"INDICATION": {
"INDICATIONIDS": 1,
"INDICATIONVALUE": {
"UNIT": "公顷",
"YEAR": 2010,
"INDICATIONID": 1,
"AREANAME": "南山区",
"ACTUALLYVALUE": "123456",
"INDICATIONVALUEID": 23
},
"INDICATIONNAME": "耕地现状面积",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 4,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATIONVALUEID": 24,
"INDICATION": {
"INDICATIONIDS": 4,
"INDICATIONVALUE": {
"UNIT": "等别",
"YEAR": 2010,
"INDICATIONID": 4,
"AREANAME": "福田区",
"ACTUALLYVALUE": "一等",
"INDICATIONVALUEID": 24
},
"INDICATIONNAME": "耕地质量",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 4,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATIONVALUEID": 25,
"INDICATION": {
"INDICATIONIDS": 4,
"INDICATIONVALUE": {
"UNIT": "等别",
"YEAR": 2011,
"INDICATIONID": 4,
"AREANAME": "福田区",
"ACTUALLYVALUE": "二等",
"INDICATIONVALUEID": 25
},
"INDICATIONNAME": "耕地质量",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 4,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATIONVALUEID": 26,
"INDICATION": {
"INDICATIONIDS": 4,
"INDICATIONVALUE": {
"UNIT": "等别",
"YEAR": 2010,
"INDICATIONID": 4,
"AREANAME": "南山区",
"ACTUALLYVALUE": "一等",
"INDICATIONVALUEID": 26
},
"INDICATIONNAME": "耕地质量",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 2,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATION": {
"INDICATIONIDS": 2,
"INDICATIONNAME": "破碎度",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 3,
"SYSTEMID": 23,
"PID": 9,
"INDICATIONSYSTEMNAME": "耕地现状",
"INDICATION": {
"INDICATIONIDS": 3,
"INDICATIONNAME": "建设用地占用耕地数量",
"SOURCE": "填报",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 22,
"SYSTEMID": 24,
"PID": 9,
"INDICATIONSYSTEMNAME": "永久基本农田",
"INDICATIONVALUEID": 27,
"INDICATION": {
"INDICATIONIDS": 22,
"INDICATIONVALUE": {
"UNIT": "公顷",
"YEAR": 2010,
"INDICATIONID": 22,
"AREANAME": "福田区",
"ACTUALLYVALUE": "12345",
"INDICATIONVALUEID": 27
},
"INDICATIONNAME": "永久基本农田面积",
"SOURCE": "一张图",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 22,
"SYSTEMID": 24,
"PID": 9,
"INDICATIONSYSTEMNAME": "永久基本农田",
"INDICATIONVALUEID": 28,
"INDICATION": {
"INDICATIONIDS": 22,
"INDICATIONVALUE": {
"UNIT": "公顷",
"YEAR": 2011,
"INDICATIONID": 22,
"AREANAME": "福田区",
"ACTUALLYVALUE": "123456",
"INDICATIONVALUEID": 28
},
"INDICATIONNAME": "永久基本农田面积",
"SOURCE": "一张图",
"CYCLE": "10年"
}
},
{
"INDICATIONIDS": 22,
"SYSTEMID": 24,
"PID": 9,
"INDICATIONSYSTEMNAME": "永久基本农田",
"INDICATIONVALUEID": 29,
"INDICATION": {
"INDICATIONIDS": 22,
"INDICATIONVALUE": {
"UNIT": "公顷",
"YEAR": 2010,
"INDICATIONID": 22,
"AREANAME": "南山区",
"ACTUALLYVALUE": "1234",
"INDICATIONVALUEID": 29
},
"INDICATIONNAME": "永久基本农田面积",
"SOURCE": "一张图",
"CYCLE": "10年"
}
},
{
"SYSTEMID": 25,
"PID": 9,
"INDICATIONSYSTEMNAME": "高标准农田"
}
]这种写法中返回的数据是一条数据一条数据返回的，即json没有任何合并现象
注意：
在写
应该以value表中数据ID输出，这样是正确的数据条数。
解决方法，在resultmap中的
mapper文件（第二种写法）
其中
将type修改成为各实体层文件
这样实体层中的注解
@JsonInclude(JsonInclude.Include.NON_NULL)@JsonProperty("id")
将会起作用；
这样写的好处，就是上层重复的数据在json文件中将合并，即system表中数据相同ID合并，indication表相同ID数据合并
结果：
[
{
"INDICATIONOVERVIEW": null,
"id": 0,
"name": "耕地现状",
"pid": 9,
"areaname": null,
"year": 0,
"warningcolor": null,
"children": [
{
"id": 1,
"name": "耕地现状面积",
"cycle": "10年",
"source": "填报",
"areas": [
{
"id": 1,
"indicationid": 1,
"year": 2010,
"areaname": "福田区",
"actuallyvalue": "12345",
"unit": "公顷"
},
{
"id": 2,
"indicationid": 1,
"year": 2011,
"areaname": "福田区",
"actuallyvalue": "12345",
"unit": "公顷"
},
{
"id": 23,
"indicationid": 1,
"year": 2010,
"areaname": "南山区",
"actuallyvalue": "123456",
"unit": "公顷"
}
]
},
{
"id": 4,
"name": "耕地质量",
"cycle": "10年",
"source": "填报",
"areas": [
{
"id": 24,
"indicationid": 4,
"year": 2010,
"areaname": "福田区",
"actuallyvalue": "一等",
"unit": "等别"
},
{
"id": 25,
"indicationid": 4,
"year": 2011,
"areaname": "福田区",
"actuallyvalue": "二等",
"unit": "等别"
},
{
"id": 26,
"indicationid": 4,
"year": 2010,
"areaname": "南山区",
"actuallyvalue": "一等",
"unit": "等别"
}
]
},
{
"id": 41,
"name": "耕地保有量",
"cycle": "110年",
"source": "填报",
"areas": []
},
{
"id": 2,
"name": "破碎度",
"cycle": "10年",
"source": "填报",
"areas": []
},
{
"id": 3,
"name": "建设用地占用耕地数量",
"cycle": "10年",
"source": "填报",
"areas": []
}
]
},
{
"INDICATIONOVERVIEW": null,
"id": 0,
"name": "永久基本农田",
"pid": 9,
"areaname": null,
"year": 0,
"warningcolor": null,
"children": [
{
"id": 22,
"name": "永久基本农田面积",
"cycle": "10年",
"source": "一张图",
"areas": [
{
"id": 27,
"indicationid": 22,
"year": 2010,
"areaname": "福田区",
"actuallyvalue": "12345",
"unit": "公顷"
},
{
"id": 28,
"indicationid": 22,
"year": 2011,
"areaname": "福田区",
"actuallyvalue": "123456",
"unit": "公顷"
},
{
"id": 29,
"indicationid": 22,
"year": 2010,
"areaname": "南山区",
"actuallyvalue": "1234",
"unit": "公顷"
}
]
}
]
},
{
"INDICATIONOVERVIEW": null,
"id": 0,
"name": "高标准农田",
"pid": 9,
"areaname": null,
"year": 0,
"warningcolor": null,
"children": []
}
]mapper文件（第三种写法）
sql语句分开写，
第一个resultmap，system表搜索字段，嵌套一个
其中collection标签中的column属性为system表与indication表关联字段；
（本文中传入4个参数，后三个参数以常数项进行传入）
第二个resultmap，indication表搜索字段，嵌套一个
第三个resultmap，value表搜索字段；
一次类推，不管搜索多少个表都可以；
postman调试：
结果：
[
{
"INDICATIONOVERVIEW": null,
"id": 23,
"name": "耕地现状",
"pid": 9,
"areaname": "深圳市",
"year": 2010,
"warningcolor": "0",
"children": [
{
"id": 1,
"name": "耕地现状面积",
"cycle": "10年",
"source": "填报",
"areas": [
{
"id": 1,
"indicationid": 1,
"year": 2010,
"areaname": "福田区",
"targetvalue": "12345",
"actuallyvalue": "12345",
"unit": "公顷",
"threshold": 0,
"warningcolor": "1(绿)"
},
{
"id": 23,
"indicationid": 1,
"year": 2010,
"areaname": "南山区",
"targetvalue": "123456",
"actuallyvalue": "123456",
"unit": "公顷"
}
],
"meaning": "耕地现状面积",
"organization": "耕地现状面积"
},
{
"id": 4,
"name": "耕地质量",
"cycle": "10年",
"source": "填报",
"areas": [
{
"id": 24,
"indicationid": 4,
"year": 2010,
"areaname": "福田区",
"targetvalue": "一等",
"actuallyvalue": "一等",
"unit": "等别",
"threshold": -10,
"warningcolor": "3(红)"
},
{
"id": 26,
"indicationid": 4,
"year": 2010,
"areaname": "南山区",
"targetvalue": "一等",
"actuallyvalue": "一等",
"unit": "等别"
}
],
"meaning": "耕地质量",
"organization": "耕地质量"
}
]
},
{
"INDICATIONOVERVIEW": null,
"id": 24,
"name": "永久基本农田",
"pid": 9,
"areaname": "深圳市",
"year": 2010,
"warningcolor": "0",
"children": [
{
"id": 22,
"name": "永久基本农田面积",
"cycle": "10年",
"source": "一张图",
"areas": [
{
"id": 27,
"indicationid": 22,
"year": 2010,
"areaname": "福田区",
"targetvalue": "12345",
"actuallyvalue": "12345",
"unit": "公顷"
},
{
"id": 29,
"indicationid": 22,
"year": 2010,
"areaname": "南山区",
"targetvalue": "1234",
"actuallyvalue": "1234",
"unit": "公顷"
}
]
}
]
},
{
"INDICATIONOVERVIEW": null,
"id": 25,
"name": "高标准农田",
"pid": 9,
"areaname": "深圳市",
"year": 2010,
"warningcolor": "0",
"children": []
}
]