Una declaración condicional de mysql compleja
1. xml
<select id="selectByExample" parameterType="com.lenovo.npi.auth.center.domain.ResExample"
resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from ac_res
<if test="_parameter != null">
<include refid="Example_Where_Clause" />
</if>
<if test="orderByClause != null and orderByClause != ''">
ORDER BY ${@com.lenovo.platform.util.Ognl@replaceOrderByClause(orderByClause)}
</if>
<include refid="ibatorgenerated_MysqlLimitSection"></include>
</select>
### 1.1 查询列 sql
<sql id="Base_Column_List">
id, rescode, res_type_code, resuri, parent, ordering, title, memo, lastmodified,
created
</sql>
### 1.2 分页sql
<sql id="ibatorgenerated_MysqlLimitSection">
<if test="page != null">
limit #{page.pageSize} offset #{page.begin}
</if>
</sql>
### 1.3 条件对象解析 sql
<sql id="Update_By_Example_Where_Clause">
<where>
<foreach collection="example.oredCriteria" item="criteria" separator="or">
<if test="criteria.valid">
<trim prefix="(" prefixOverrides="and" suffix=")">
<foreach collection="criteria.criteria" item="criterion">
<choose>
<when test="criterion.noValue">
and ${criterion.condition}
</when>
<when test="criterion.singleValue">
and ${criterion.condition} #{criterion.value}
</when>
<when test="criterion.betweenValue">
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
</when>
<when test="criterion.listValue">
and ${criterion.condition}
<foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
#{listItem}
</foreach>
</when>
</choose>
</foreach>
</trim>
</if>
</foreach>
</where>
</sql>
2. Objeto de condición java
getter / setter 略
2.1 ResEjemplo
import com.lenovo.platform.common.vo.Page;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
public class ResExample {
/**
* 查询关键字
*/
private String queryKey;
/**
* 排序语句
*/
protected String orderByClause;
protected boolean distinct;
/**
* 动态查询字段
*/
protected List<Criteria> oredCriteria;
/**
* 分页参数
*/
protected Page page;
public ResExample() {
oredCriteria = new ArrayList<Criteria>();
}
}
2.2 Criterios
Para el empalme dinámico de las condiciones de entrada, considerando las diversas situaciones involucradas en cada parámetro, el siguiente es un ejemplo de id:
public Criteria andIdIsNull() {
addCriterion("id is null");
return (Criteria) this;
}
public Criteria andIdIsNotNull() {
addCriterion("id is not null");
return (Criteria) this;
}
public Criteria andIdEqualTo(Integer value) {
addCriterion("id =", value, "id");
return (Criteria) this;
}
public Criteria andIdNotEqualTo(Integer value) {
addCriterion("id <>", value, "id");
return (Criteria) this;
}
public Criteria andIdGreaterThan(Integer value) {
addCriterion("id >", value, "id");
return (Criteria) this;
}
public Criteria andIdGreaterThanOrEqualTo(Integer value) {
addCriterion("id >=", value, "id");
return (Criteria) this;
}
public Criteria andIdLessThan(Integer value) {
addCriterion("id <", value, "id");
return (Criteria) this;
}
public Criteria andIdLessThanOrEqualTo(Integer value) {
addCriterion("id <=", value, "id");
return (Criteria) this;
}
public Criteria andIdIn(List<Integer> values) {
addCriterion("id in", values, "id");
return (Criteria) this;
}
public Criteria andIdNotIn(List<Integer> values) {
addCriterion("id not in", values, "id");
return (Criteria) this;
}
public Criteria andIdBetween(Integer value1, Integer value2) {
addCriterion("id between", value1, value2, "id");
return (Criteria) this;
}
public Criteria andIdNotBetween(Integer value1, Integer value2) {
addCriterion("id not between", value1, value2, "id");
return (Criteria) this;
}
2.3 página
public class Page {
private static long maxPageSize = 1000;
// 分页查询开始记录位置(Include)*
private long begin;
// 分页查看下结束位置(Exclude)
private long end;
// 每页显示记录数*
private long pageSize = 0;
// 查询结果总记录数
private long rowTotal = 0;
// 当前页码*
private long current = 1;
// 总共页数
private long pageTotal = 0;
public Page() {
}
}
3. Java objeto Ognl
Utilice métodos externos en xml de las siguientes formas
ORDER BY ${@com.lenovo.platform.util.Ognl@replaceOrderByClause(orderByClause)}
Método externo
import org.apache.commons.lang.StringEscapeUtils;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.StringUtils;
import java.util.Arrays;
import java.util.stream.Collectors;
public class Ognl {
private static final String ORDER_BY_ASC = "ASC";
private static final String ORDER_BY_DESC = "DESC";
private static final String REGEX_ORDER_BY = "^[a-zA-z0-9_]+$";
/**
* 解析排序字符串
*
* @param orderByClause : "field0,field1 asc,field2 des,..."
* @return ："field0,field1 asc,field2 des,..."
*/
public static String replaceOrderByClause(String orderByClause){
String s = StringEscapeUtils.escapeSql(orderByClause);
String[] clauses = s.split(",");
if (ArrayUtils.isEmpty(clauses)) {
return null;
}
return Arrays.stream(clauses).map(c -> {
String[] o = c.split(" ");
if (ArrayUtils.isEmpty(o)) {
return null;
}
//check field
if (!o[0].matches(REGEX_ORDER_BY)) {
return null;
}
//check sort
if (o.length == 2) {
if (StringUtils.equalsIgnoreCase(ORDER_BY_ASC, o[1])
|| StringUtils.equalsIgnoreCase(ORDER_BY_DESC, o[1])) {
return c;
}
}
return o[0];
}).filter(x -> StringUtils.isNotBlank(x))
.collect(Collectors.joining(","));
}
}