java后台树形结构展示---懒加载

一、数据库设计

 

 

 二、实体类：entity

import com.joyoung.cloud.security.common.validatedGroup.Add;
import com.joyoung.cloud.security.common.validatedGroup.Modify;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import lombok.experimental.Accessors;

import javax.persistence.Id;
import javax.persistence.Transient;
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Null;
import javax.validation.constraints.Pattern;
import java.io.Serializable;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;

/**
 * 公司表(SysCompany)实体类
 *
 * @author yangyuwei
 * @since 2019-06-06 13:45:23
 */
@ApiModel(value = "公司类")
@Data
@Accessors(chain = true)
public class SysCompany implements Serializable {
 private static final long serialVersionUID = 600959061181555399L;
 @ApiModelProperty(value = "主键Id")
 @Id
 @Null(message = "{add_id}", groups = {Add.class})
 @NotNull(message = "{modify_id}", groups = {Modify.class})
 private String id;
 //上级公司id
 @ApiModelProperty(value = "父Id")
 private String parentId;
 //公司名称
 @ApiModelProperty(value = "公司名称")
 @NotBlank(message = "{name_null}")
 @Pattern(regexp = "^[\\s\\S]{1,20}$", message = "{name_rule}")
 private String coName;
 //公司简称
 @ApiModelProperty(value = "公司简称")
 private String coAbbr;
 //公司编号
 @ApiModelProperty(value = "公司编号")
 private String coCode;
 //公司地址
 @ApiModelProperty(value = "公司地址")
 private String coAddr;
 //邮编
 @ApiModelProperty(value = "邮编")
 @Pattern(regexp = "^$|[0-9]{6}$", message = "{zipCode_error}")
 private String zipCode;
 //法人名称
 @ApiModelProperty(value = "法人名称")
 private String legalName;
 //法定代表人
 @ApiModelProperty(value = "法定代表人")
 private String legalRep;
 //税号
 @ApiModelProperty(value = "税号")
 private String taxId;
 //电话号码("XXX-XXXXXXX"、"XXXX-XXXXXXXX"、"XXX-XXXXXXX"、"XXX-XXXXXXXX"、"XXXXXXX"和"XXXXXXXX)
// @Pattern(regexp = "^(\\(\\d{3,4}\\)|\\d{3,4}-|\\s)?\\d{7,14}$", message = "请输入正确的电话号码")
 @ApiModelProperty(value = "电话号码")
 private String tel;
 //开户银行名称
 @ApiModelProperty(value ="开户银行名称")
 private String bankName;
 //开户银行账号
 @ApiModelProperty(value = "开户银行账号")
 private String bankAcct;
 //创建人id
 private String crtUser;
 //创建人名称
 private String crtName;
 //创建时间
 private Date crtTime;
 //最后修改人id
 private String updUser;
 //最后修改人名称
 private String updName;
 //最后修改时间
 private Date updTime;
 //备注
 private String remark;
 //逻辑删除标识：1=删除；0=未删除
 private Integer delFlag;

 private String attr1;

 private String attr2;

 private String attr3;

 /*****************************以下为添加字段*********************************/
 @Transient
 private Boolean hasChecked;
 @Transient
 private Boolean hasChildren;
 @Transient
 private List children = new LinkedList();

}

三、controller

@ApiOperation(value = "懒加载查询列表")
@GetMapping("/children")
public List getChildren(SysCompany sysCompany) {
 return service.getChildren(sysCompany);
}

四、service

@Override
public List getChildren(SysCompany sysCompany) {
    List companyList = dao.selectCompanyInfo(sysCompany);
    if (StringUtils.isNotBlank(sysCompany.getCoName())) {
        return getTree(sysCompany);
 }
 return companyList;
}

/**
这里一般将此方法放在entity里面
*/

private List getTree(SysCompany sysCompany) {
    Map map = dao.selectByCompany(sysCompany);
    List tree = new ArrayList<>();
    map.forEach((id, obj) -> {
        if (map.containsKey(obj.getParentId())) {
            map.get(obj.getParentId()).getChildren().add(obj);
 } else {
 tree.add(obj);
 }
 });
 return tree;
}

五、dao

public List selectCompanyInfo(SysCompany sysCompany);

六、mapper

<sql id="sys_param">
    c.id,
    c.parent_id,
    c.co_name,
    c.co_abbr,
    c.co_code,
    c.co_addr,
    c.zip_code,
    c.legal_name,
    c.legal_rep,
    c.tax_id,
    c.tel,
    c.bank_name,
    c.bank_acct,
    c.crt_user,
    c.crt_name,
    c.crt_time,
    c.upd_user,
    c.upd_name,
    c.upd_time,
    c.remark,
    c.del_flag
sql>
<select id="selectCompanyInfo" resultMap="SysCompanyMap"
 parameterType="com.joyoung.cloud.security.common.entity.admin.SysCompany">
 SELECT
 <include refid="sys_param"/>,EXISTS (SELECT 1 from sys_company sc where sc.parent_id=c.id and sc.del_flag=0) as
 hasChildren
 FROM
 sys_company c
 WHERE
 c.del_flag = 0
 <if test="coName!=null">
 and c.co_name like concat ('%',#{coName},'%')
 if>
 <if test="parentId !=null and parentId !=''">
 and c.parent_id = #{parentId}
 if>
 <if test="parentId == null || parentId == ''">
 and c.parent_id is null
 if>
select>