com.yuehuanghun.mybatis.milu.criteria.builder.QuerySqlTemplateBuilder Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of mybatis-milu Show documentation
Show all versions of mybatis-milu Show documentation
A mybatis orm enhance framework.
/*
* Copyright 2020-2022 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.yuehuanghun.mybatis.milu.criteria.builder;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import org.apache.ibatis.mapping.ResultFlag;
import org.apache.ibatis.mapping.ResultMap;
import org.apache.ibatis.mapping.ResultMapping;
import com.yuehuanghun.mybatis.milu.annotation.JoinMode;
import com.yuehuanghun.mybatis.milu.criteria.QueryPredicate;
import com.yuehuanghun.mybatis.milu.criteria.QueryPredicateImpl;
import com.yuehuanghun.mybatis.milu.data.SqlBuildingHelper;
import com.yuehuanghun.mybatis.milu.exception.SqlExpressionBuildingException;
import com.yuehuanghun.mybatis.milu.generic.GenericProviderContext;
import com.yuehuanghun.mybatis.milu.mapping.MiluMapperBuilderAssistant;
import com.yuehuanghun.mybatis.milu.metamodel.Entity;
import com.yuehuanghun.mybatis.milu.metamodel.Entity.Attribute;
import com.yuehuanghun.mybatis.milu.metamodel.Entity.PluralAttribute;
import com.yuehuanghun.mybatis.milu.tool.Segment;
import com.yuehuanghun.mybatis.milu.tool.StringUtils;
import lombok.AllArgsConstructor;
import lombok.Data;
public class QuerySqlTemplateBuilder extends SqlTemplateBuilder {
private final QueryPredicate predicate;
private final static Pattern ORDER_BY_PT = Pattern.compile("^\\s*ORDER BY.*$");
private final static List ID_FLAG_LIST = Arrays.asList(ResultFlag.ID);
public QuerySqlTemplateBuilder(GenericProviderContext context, QueryPredicate queryPredicate) {
super(context);
this.predicate = queryPredicate;
}
public BuildResult build() {
Set selectAttrs = Collections.emptySet();
Set exselectAttrs = Collections.emptySet();
Map joinModeMap = Collections.emptyMap();
if (QueryPredicateImpl.class.isInstance(predicate)) {
selectAttrs = ((QueryPredicateImpl) predicate).getSelectAttrs();
exselectAttrs = ((QueryPredicateImpl) predicate).getExselectAttrs();
joinModeMap = ((QueryPredicateImpl) predicate).getJoinModeMap();
}
if(selectAttrs.isEmpty()) {
selectAttrs.add("*");
}
Map> selectEntityAttrMap = analyseAttrs(selectAttrs);
Map> exselectEntityAttrMap = analyseAttrs(exselectAttrs);
StringBuilder expressionBuilder = new StringBuilder(256);
Set properties = new HashSet<>();
predicate.renderSqlTemplate(context, expressionBuilder, properties, 0);
if(!selectEntityAttrMap.isEmpty()) {
selectEntityAttrMap.forEach((attrName, attributes) -> {
if(StringUtils.isNotBlank(attrName)) {
attributes.forEach(subAttr -> {
properties.add(attrName + StringUtils.capitalize(subAttr.getName()));
});
}
});
}
SqlBuildingHelper.analyseDomain(entity, properties, tableAliasDispacher, configuration, joinExpressMap,
joinQueryColumnNap, joinModeMap);
StringBuilder sqlBuilder = new StringBuilder(1024).append(Segment.SCRIPT_LABEL);
sqlBuilder.append(Segment.SELECT);
if (QueryPredicateImpl.class.isInstance(predicate) && ((QueryPredicateImpl) predicate).isDistinct()) {
sqlBuilder.append(Segment.DISTINCT);
}
Iterator>> it = selectEntityAttrMap.entrySet().iterator();
boolean firstColumn = true;
while(it.hasNext()) {
Entry> entityEntry = it.next();
String mainEntityAttrName = entityEntry.getKey();
List exselectAttrNameList = exselectEntityAttrMap.containsKey(mainEntityAttrName) ? exselectEntityAttrMap.get(mainEntityAttrName).stream().map(Attribute::getName).collect(Collectors.toList()) : Collections.emptyList();
for(Attribute attr : entityEntry.getValue()) {
if (!exselectAttrNameList.isEmpty() && exselectAttrNameList.contains(attr.getName())) {
continue;
}
if (firstColumn) {
firstColumn = false;
} else {
sqlBuilder.append(Segment.COMMA_B);
}
if (StringUtils.isBlank(mainEntityAttrName)) { // 没有关联查询时，不需要使用表别名
if(!joinExpressMap.isEmpty()) {
sqlBuilder.append(mainTableAlias).append(Segment.DOT);
}
} else {
sqlBuilder.append(tableAliasDispacher.dispach(Segment.ATTR_ + mainEntityAttrName)).append(Segment.DOT); //表别名
}
SqlBuildingHelper.appendIdentifier(sqlBuilder, attr.getColumnName(), configuration);
if(StringUtils.isNotBlank(mainEntityAttrName)) { //处理关联表字段别名
String tableAlias = tableAliasDispacher.dispach(Segment.ATTR_ + mainEntityAttrName);
String columnAlias = Segment.UNDER_LINE + tableAlias + Segment.UNDER_LINE + attr.getName();
sqlBuilder.append(Segment.SPACE);
SqlBuildingHelper.appendIdentifier(sqlBuilder, columnAlias, configuration);
}
}
}
sqlBuilder.append(Segment.FROM_B);
buildTableSegment(sqlBuilder);
String sqlTemplateTmp = expressionBuilder.toString();
if (StringUtils.isNotBlank(sqlTemplateTmp)) {
sqlTemplateTmp = renderConditionSql(sqlTemplateTmp, properties);
if (!ORDER_BY_PT.matcher(sqlTemplateTmp).matches()) { // 如果没有查询条件时，则不用加WHERE
sqlBuilder.append(Segment.WHERE_B);
}
sqlBuilder.append(sqlTemplateTmp);
}
sqlBuilder.append(Segment.SCRIPT_LABEL_END);
//是否需要构造新的ResultMap，如果查询的字段只有主表的，就不需要
List resultMappings = new ArrayList<>();
if(selectEntityAttrMap.size() > 1 || (selectEntityAttrMap.size() == 1 && !selectEntityAttrMap.containsKey(StringUtils.EMPTY))) {
MiluMapperBuilderAssistant assistant = new MiluMapperBuilderAssistant(configuration, null); //resource ignore
selectEntityAttrMap.forEach((mainEntityAttrName, attributes) -> {
if(StringUtils.isBlank(mainEntityAttrName)) {
attributes.forEach(attribute -> {
ResultMapping resultMapping = assistant.buildResultMapping(attribute.getOwner().getJavaType(), attribute.getName(), attribute.getColumnName(), attribute.getJavaType(), attribute.getJdbcType(), null, null, null, null, attribute.getTypeHandler(), attribute.isId() ? ID_FLAG_LIST : null);
resultMappings.add(resultMapping);
});
} else {
String tableAlias = tableAliasDispacher.dispach(Segment.ATTR_ + mainEntityAttrName);
List refResultMappings = new ArrayList<>();
attributes.forEach(attribute -> {
String columnAlias = Segment.UNDER_LINE + tableAlias + Segment.UNDER_LINE + attribute.getName();
ResultMapping resultMapping = assistant.buildResultMapping(attribute.getOwner().getJavaType(), attribute.getName(), columnAlias, attribute.getJavaType(), attribute.getJdbcType(), null, null, null, null, attribute.getTypeHandler(), attribute.isId() ? ID_FLAG_LIST : null);
refResultMappings.add(resultMapping);
});
String resultMapId = entity.getJavaType().getName() + "#" + mainEntityAttrName + "$" + (refResultMappings.hashCode() + 31 * predicate.hashCode());
Attribute attribute = entity.getAttribute(mainEntityAttrName);
if(!configuration.hasResultMap(resultMapId)) {
Class javaType = attribute.getJavaType();
if(attribute instanceof PluralAttribute) {
javaType = ((PluralAttribute) attribute).getElementClass();
}
try {
configuration.addResultMap(new ResultMap.Builder(configuration, resultMapId, javaType, refResultMappings, true).build());
} catch (IllegalArgumentException e) {
// 并发下的重复添加引起的异常，忽略
}
}
ResultMapping resultMapping = assistant.buildResultMapping(attribute.getOwner().getJavaType(), attribute.getName(), null, attribute.getJavaType(), attribute.getJdbcType(), null, resultMapId, null, null, attribute.getTypeHandler(), null);
resultMappings.add(resultMapping);
}
});
}
return new BuildResult(sqlBuilder.toString(), resultMappings);
}
private Map> analyseAttrs(Set attrs) {
Map> entityAttrsMap = new HashMap<>();
for (String attr : attrs) {
//主体
if ("*".equals(attr)) {
List list = entityAttrsMap.computeIfAbsent(StringUtils.EMPTY, key -> { //空表示主体
return new ArrayList<>();
});
Iterator it = entity.getAttributes().iterator();
while (it.hasNext()) {
Attribute attribute = it.next();
if (attribute.isSelectable()) {
list.add(attribute);
}
}
continue;
}
//外键/关联实体
if(attr.contains("*")) {
String refAttr = attr.substring(0, attr.indexOf("*"));
Attribute attribute = entity.getAttribute(refAttr);
if(attribute == null) {
throw new SqlExpressionBuildingException(String.format("表达式%s找不到相关实体属性：%s", attr, refAttr));
}
if(!attribute.isReference()) {
throw new SqlExpressionBuildingException(String.format("表达式%s中%s不是关联（外键）属性", attr, refAttr));
}
Entity refEntity = configuration.getMetaModel().getEntity(attribute.getEntityClass());
if(refEntity == null) {
throw new SqlExpressionBuildingException(String.format("关联（外键）属性%s无对应实体类信息", attribute.getEntityClass().getName()));
}
List list = entityAttrsMap.computeIfAbsent(refAttr, key -> {
return new ArrayList<>();
});
Iterator it = refEntity.getAttributes().iterator();
while (it.hasNext()) {
Attribute curAttr = it.next();
if (curAttr.isSelectable()) {
list.add(curAttr);
}
}
continue;
}
//主体的属性
if(entity.hasAttribute(attr)) {
entityAttrsMap.computeIfAbsent(StringUtils.EMPTY, key -> {
return new ArrayList<>();
}).add(entity.getAttribute(attr));
continue;
}
//外键实体的属性
Map possiblePropertyMap = SqlBuildingHelper.possibleProperty(attr);
Iterator> possiblePropertyIt = possiblePropertyMap.entrySet().iterator();
boolean match = false;
while(possiblePropertyIt.hasNext()) {
Entry possibleProperty = possiblePropertyIt.next();
if(!entity.hasAttribute(possibleProperty.getKey())) {
continue;
}
Attribute refAttribute = entity.getAttribute(possibleProperty.getKey());
Entity refAttrEntity = configuration.getMetaModel().getEntity(refAttribute.getEntityClass());
if(!refAttrEntity.hasAttribute(possibleProperty.getValue())) {
continue;
}
List list = entityAttrsMap.computeIfAbsent(possibleProperty.getKey(), key -> {
return new ArrayList<>();
});
list.add(refAttrEntity.getAttribute(possibleProperty.getValue()));
match = true;
break;
}
if(!match) {
throw new SqlExpressionBuildingException(String.format("未知的属性：%s", attr));
}
}
return entityAttrsMap;
}
@Data
@AllArgsConstructor
public static class BuildResult {
private String sqlTemplate;
private List resultMappings;
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy