Hibernate java 条件查询具有多个集合成员（如标签）的实例
Hibernate java Criteria query for instances with multiple collection members like tag
请帮我编写一个 Java 条件对象查询，以查找包含所有所需成员的集合的所有项目。基本上，我需要 "and" 条件，而不是 "or" 它。这与 SO 文章和标签完全一样：搜索带有标签 "java" 和 "hibernate" 的文章，结果应该只有带有两个标签的文章（更多标签也可以）。喜欢这个:)
我的实体名为 "Solution"，它有一组通过两列映射 table 映射的标签实体。我从下面的研究中了解到我需要一个 DetachedQuery。关键例程（请参阅下面的搜索服务实现）运行但 returns 在测试用例中没有结果。
到目前为止的研究 - 如果我知道如何更好地将 HQL 转换为 Criteria，我会走得更远：/
- 与我的问题完全相同，@Firo 提供了 Criteria 代码，但它有一个小问题：Hibernate Criteria to match against all child collection
- 仅 HQL 代码：Matching *ALL* items in a list with Hibernate criteria
- 仅 HQL 代码：Hibernate: Select entities where collection contains all of the specified valus
- 讨论和 HQL：https://vladmihalcea.com/sql-query-parent-rows-all-children-match-filtering-criteria
- HQL 写的不错：http://www.sergiy.ca/how-to-write-many-to-many-search-queries-in-mysql-and-hibernate
编辑 感谢@samabcde，我将查询方法更正为使用Restrictions.eqProperty，不再有class 转换异常。
通过打开调试日志记录，我可以看到生成的 SQL（由于急切获取策略，所以很长）。它看起来不对，尤其是 "this_.ID=this_.ID" 部分 - 这是微不足道的事实。
select this_.ID as ID1_39_1_, this_.NAME as NAME2_39_1_,
tags2_.SOL_ID as SOL_ID1_38_3_, tag3_.ID as TAG_ID2_38_3_,
tag3_.ID as ID1_40_0_, tag3_.NAME as NAME2_40_0_
from SOLUTION this_
left outer join SOL_TAG_MAP tags2_ on this_.ID=tags2_.SOL_ID
left outer join TAG tag3_ on tags2_.TAG_ID=tag3_.ID
where ? = (select count(t1_.NAME) as y0_ from SOLUTION this_
inner join SOL_TAG_MAP tags3_ on this_.ID=tags3_.SOL_ID
inner join TAG t1_ on tags3_.TAG_ID=t1_.ID
where this_.ID=this_.ID and t1_.NAME in (?, ?))
我没有得到预期的答案 - 测试用例中的查询结果（见下文）是空的，我希望它能找到 1 行。
很抱歉，为了完整起见，显示的文件很长，但为了简洁起见，我跳过了导入语句。我可能在做一些愚蠢的事情，专家可以立即指出，在此先感谢。
实体解决方案
@Entity
@Table(name = "SOLUTION")
public class Solution implements Serializable {
private static final long serialVersionUID = 745945642089325612L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "ID", nullable = false, updatable = false, columnDefinition = "INT")
private Long id;
@Column(name = "NAME", nullable = false, columnDefinition = "VARCHAR(100)")
private String name;
// Fetch eagerly to make serialization easy
@ManyToMany(fetch = FetchType.EAGER)
@JoinTable(name = SolTagMap.TABLE_NAME, //
joinColumns = { @JoinColumn(name = SolTagMap.SOL_ID_COL_NAME) }, //
inverseJoinColumns = { @JoinColumn(name = SolTagMap.TAG_ID_COL_NAME) })
private Set<Tag> tags = new HashSet<>(0);
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Set<Tag> getTags() {
return tags;
}
public void setTags(Set<Tag> tags) {
this.tags = tags;
}
@Override
public String toString() {
return this.getClass().getName() + "[id=" + getId() + ", name=" + getName() + ", tags="
+ getTags() + "]";
}
}
实体图table
@Entity
@IdClass(SolTagMapKey.class)
@Table(name = SolTagMap.TABLE_NAME)
public class SolTagMap implements Serializable {
// Define constants so names can be reused in many-many annotation.
/* package */ static final String TABLE_NAME = "SOL_TAG_MAP";
/* package */ static final String SOL_ID_COL_NAME = "SOL_ID";
/* package */ static final String TAG_ID_COL_NAME = "TAG_ID";
private static final long serialVersionUID = -7814665924253912856L;
@Embeddable
public static class SolTagMapKey implements Serializable {
private static final long serialVersionUID = -503957020456645384L;
private Long solId;
private Long tagId;
@Override
public boolean equals(Object that) {
if (that == null)
return false;
if (!(that instanceof SolTagMapKey))
return false;
SolTagMapKey thatPK = (SolTagMapKey) that;
return Objects.equals(solId, thatPK.solId) && Objects.equals(tagId, thatPK.tagId);
}
@Override
public int hashCode() {
return Objects.hash(solId, tagId);
}
@Override
public String toString() {
return this.getClass().getName() + "[solId=" + solId + ", tagId=" + tagId + "]";
}
}
@Id
@Column(name = SolTagMap.SOL_ID_COL_NAME, nullable = false, updatable = false, columnDefinition = "INT")
private Long solId;
@Id
@Column(name = SolTagMap.TAG_ID_COL_NAME, nullable = false, updatable = false, columnDefinition = "INT")
private Long tagId;
public Long getSolId() {
return solId;
}
public void setSolId(Long solId) {
this.solId = solId;
}
public Long getTagId() {
return tagId;
}
public void setTagId(Long tagId) {
this.tagId = tagId;
}
@Override
public boolean equals(Object that) {
if (that == null)
return false;
if (!(that instanceof SolTagMap))
return false;
SolTagMap thatObj = (SolTagMap) that;
return Objects.equals(solId, thatObj.solId) && Objects.equals(tagId, thatObj.tagId);
}
@Override
public int hashCode() {
return Objects.hash(solId, tagId);
}
@Override
public String toString() {
return this.getClass().getName() + "[solId=" + solId + ", tagId=" + tagId + "]";
}
}
实体标签
@Entity
@Table(name = "TAG")
public class Tag implements Serializable {
private static final long serialVersionUID = -288462280366502647L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "ID", nullable = false, updatable = false, columnDefinition = "INT")
private Long id;
@Column(name = "NAME", nullable = false, columnDefinition = "VARCHAR(100)")
private String name;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public boolean equals(Object that) {
if (that == null)
return false;
if (!(that instanceof Tag))
return false;
Tag thatObj = (Tag) that;
return Objects.equals(id, thatObj.id);
}
@Override
public int hashCode() {
return Objects.hash(id, name);
}
@Override
public String toString() {
return this.getClass().getName() + "[id=" + id + ", name=" + name + "]";
}
}
搜索服务实施
@Service("simpleSolutionSearchService")
@Transactional
public class SimpleSolutionSearchServiceImpl implements SimpleSolutionSearchService {
@Autowired
private SessionFactory sessionFactory;
// This works fine
public List<Solution> findSolutions() {
Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Solution.class);
// Hibernate should coalesce the results, yielding only solutions
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}
// This throws
public List<Solution> findSolutionsWithTags(String[] requiredTags) {
final String parentAlias = "sol";
final String collFieldAlias = "t";
final String tagValueField = collFieldAlias + ".name";
DetachedCriteria subquery = DetachedCriteria.forClass(Solution.class)
.add(Restrictions.eqProperty("id", parentAlias + ".id"))
.createAlias("tags", collFieldAlias) //
.add(Restrictions.in(tagValueField, requiredTags)) //
.setProjection(Projections.count(tagValueField));
Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Solution.class, parentAlias)
.add(Subqueries.eq((long) requiredTags.length, subquery));
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}
}
解决方案库
public interface SimpleSolutionRepository extends CrudRepository<Solution, Long> {
}
标签库
public interface SimpleTagRepository extends CrudRepository<Tag, Long> {
}
测试用例
@RunWith(SpringRunner.class)
@SpringBootTest
public class SolutionServiceTest {
private static final Logger logger = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
@Autowired
private SimpleSolutionRepository solutionRepository;
@Autowired
private SimpleTagRepository tagRepository;
@Autowired
private SimpleSolutionSearchService searchService;
@Test
public void testRepositories() throws Exception {
final String tagName1 = "tag name 1";
final String tagName2 = "tag name 2";
Tag t1 = new Tag();
t1.setName(tagName1);
t1 = tagRepository.save(t1);
Assert.assertNotNull(t1.getId());
logger.info("Created tag {}", t1);
Tag t2 = new Tag();
t2.setName(tagName2);
t2 = tagRepository.save(t2);
Assert.assertNotNull(t2.getId());
logger.info("Created tag {}", t2);
Solution s1 = new Solution();
s1.setName("solution one tag");
s1.getTags().add(t1);
s1 = solutionRepository.save(s1);
Assert.assertNotNull(s1.getId());
logger.info("Created solution {}", s1);
Solution s2 = new Solution();
s2.setName("solution two tags");
s2.getTags().add(t1);
s2.getTags().add(t2);
s2 = solutionRepository.save(s2);
Assert.assertNotNull(s2.getId());
logger.info("Created solution {}", s1);
List<Solution> sols = searchService.findSolutions();
Assert.assertTrue(sols.size() == 2);
for (Solution s : sols)
logger.info("Found solution {}", s);
String[] searchTags = { tagName1, tagName2 };
List<Solution> taggedSols = searchService.findSolutionsWithTags(searchTags);
// EXPECT ONE OBJECT BUT GET ZERO
Assert.assertTrue(taggedSols.size() == 1);
}
}
Restrictions.eq is for compare property with a value, Restrictions.propertyEq 将 属性 与另一个 属性 进行比较。因此，代码将 parentAlias + ".id" 视为字符串值以与 ID 属性 进行比较，而不是父 ID 属性，这导致 ClassCaseException。
没有找到记录的问题，where this_.ID=this_.ID说出原因。 Hibernate 认为子查询中的 id 属性 引用父查询 Solution，而不是子查询 Solution。在这种情况下，应向子查询提供别名以区分 id 属性。
public List<Solution> findSolutionsWithTags(String[] requiredTags) {
final String parentAlias = "sol";
final String childAlias = "subSol";
final String collFieldAlias = "t";
final String tagValueField = collFieldAlias + ".name";
DetachedCriteria subquery = DetachedCriteria.forClass(Solution.class, childAlias)
// Throws ClassCastException; apparently sol.id isn't replaced with an ID value?
// Problem should be due to following line
//.add(Restrictions.eq("id", parentAlias + ".id"))
// Use eqProperty instead
.add(Restrictions.eqProperty(childAlias + ".id", parentAlias + ".id"))
.createAlias("tags", collFieldAlias) //
.add(Restrictions.in(tagValueField, requiredTags)) //
.setProjection(Projections.count(tagValueField));
Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Solution.class, parentAlias)
.add(Subqueries.eq((long) requiredTags.length, subquery));
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}
请帮我编写一个 Java 条件对象查询，以查找包含所有所需成员的集合的所有项目。基本上，我需要 "and" 条件，而不是 "or" 它。这与 SO 文章和标签完全一样：搜索带有标签 "java" 和 "hibernate" 的文章，结果应该只有带有两个标签的文章（更多标签也可以）。喜欢这个:)
我的实体名为 "Solution"，它有一组通过两列映射 table 映射的标签实体。我从下面的研究中了解到我需要一个 DetachedQuery。关键例程（请参阅下面的搜索服务实现）运行但 returns 在测试用例中没有结果。
到目前为止的研究 - 如果我知道如何更好地将 HQL 转换为 Criteria，我会走得更远：/
- 与我的问题完全相同，@Firo 提供了 Criteria 代码，但它有一个小问题：Hibernate Criteria to match against all child collection
- 仅 HQL 代码：Matching *ALL* items in a list with Hibernate criteria
- 仅 HQL 代码：Hibernate: Select entities where collection contains all of the specified valus
- 讨论和 HQL：https://vladmihalcea.com/sql-query-parent-rows-all-children-match-filtering-criteria
- HQL 写的不错：http://www.sergiy.ca/how-to-write-many-to-many-search-queries-in-mysql-and-hibernate
编辑 感谢@samabcde，我将查询方法更正为使用Restrictions.eqProperty，不再有class 转换异常。
通过打开调试日志记录，我可以看到生成的 SQL（由于急切获取策略，所以很长）。它看起来不对，尤其是 "this_.ID=this_.ID" 部分 - 这是微不足道的事实。
select this_.ID as ID1_39_1_, this_.NAME as NAME2_39_1_,
tags2_.SOL_ID as SOL_ID1_38_3_, tag3_.ID as TAG_ID2_38_3_,
tag3_.ID as ID1_40_0_, tag3_.NAME as NAME2_40_0_
from SOLUTION this_
left outer join SOL_TAG_MAP tags2_ on this_.ID=tags2_.SOL_ID
left outer join TAG tag3_ on tags2_.TAG_ID=tag3_.ID
where ? = (select count(t1_.NAME) as y0_ from SOLUTION this_
inner join SOL_TAG_MAP tags3_ on this_.ID=tags3_.SOL_ID
inner join TAG t1_ on tags3_.TAG_ID=t1_.ID
where this_.ID=this_.ID and t1_.NAME in (?, ?))
我没有得到预期的答案 - 测试用例中的查询结果（见下文）是空的，我希望它能找到 1 行。
很抱歉，为了完整起见，显示的文件很长，但为了简洁起见，我跳过了导入语句。我可能在做一些愚蠢的事情，专家可以立即指出，在此先感谢。
实体解决方案
@Entity
@Table(name = "SOLUTION")
public class Solution implements Serializable {
private static final long serialVersionUID = 745945642089325612L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "ID", nullable = false, updatable = false, columnDefinition = "INT")
private Long id;
@Column(name = "NAME", nullable = false, columnDefinition = "VARCHAR(100)")
private String name;
// Fetch eagerly to make serialization easy
@ManyToMany(fetch = FetchType.EAGER)
@JoinTable(name = SolTagMap.TABLE_NAME, //
joinColumns = { @JoinColumn(name = SolTagMap.SOL_ID_COL_NAME) }, //
inverseJoinColumns = { @JoinColumn(name = SolTagMap.TAG_ID_COL_NAME) })
private Set<Tag> tags = new HashSet<>(0);
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Set<Tag> getTags() {
return tags;
}
public void setTags(Set<Tag> tags) {
this.tags = tags;
}
@Override
public String toString() {
return this.getClass().getName() + "[id=" + getId() + ", name=" + getName() + ", tags="
+ getTags() + "]";
}
}
实体图table
@Entity
@IdClass(SolTagMapKey.class)
@Table(name = SolTagMap.TABLE_NAME)
public class SolTagMap implements Serializable {
// Define constants so names can be reused in many-many annotation.
/* package */ static final String TABLE_NAME = "SOL_TAG_MAP";
/* package */ static final String SOL_ID_COL_NAME = "SOL_ID";
/* package */ static final String TAG_ID_COL_NAME = "TAG_ID";
private static final long serialVersionUID = -7814665924253912856L;
@Embeddable
public static class SolTagMapKey implements Serializable {
private static final long serialVersionUID = -503957020456645384L;
private Long solId;
private Long tagId;
@Override
public boolean equals(Object that) {
if (that == null)
return false;
if (!(that instanceof SolTagMapKey))
return false;
SolTagMapKey thatPK = (SolTagMapKey) that;
return Objects.equals(solId, thatPK.solId) && Objects.equals(tagId, thatPK.tagId);
}
@Override
public int hashCode() {
return Objects.hash(solId, tagId);
}
@Override
public String toString() {
return this.getClass().getName() + "[solId=" + solId + ", tagId=" + tagId + "]";
}
}
@Id
@Column(name = SolTagMap.SOL_ID_COL_NAME, nullable = false, updatable = false, columnDefinition = "INT")
private Long solId;
@Id
@Column(name = SolTagMap.TAG_ID_COL_NAME, nullable = false, updatable = false, columnDefinition = "INT")
private Long tagId;
public Long getSolId() {
return solId;
}
public void setSolId(Long solId) {
this.solId = solId;
}
public Long getTagId() {
return tagId;
}
public void setTagId(Long tagId) {
this.tagId = tagId;
}
@Override
public boolean equals(Object that) {
if (that == null)
return false;
if (!(that instanceof SolTagMap))
return false;
SolTagMap thatObj = (SolTagMap) that;
return Objects.equals(solId, thatObj.solId) && Objects.equals(tagId, thatObj.tagId);
}
@Override
public int hashCode() {
return Objects.hash(solId, tagId);
}
@Override
public String toString() {
return this.getClass().getName() + "[solId=" + solId + ", tagId=" + tagId + "]";
}
}
实体标签
@Entity
@Table(name = "TAG")
public class Tag implements Serializable {
private static final long serialVersionUID = -288462280366502647L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "ID", nullable = false, updatable = false, columnDefinition = "INT")
private Long id;
@Column(name = "NAME", nullable = false, columnDefinition = "VARCHAR(100)")
private String name;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public boolean equals(Object that) {
if (that == null)
return false;
if (!(that instanceof Tag))
return false;
Tag thatObj = (Tag) that;
return Objects.equals(id, thatObj.id);
}
@Override
public int hashCode() {
return Objects.hash(id, name);
}
@Override
public String toString() {
return this.getClass().getName() + "[id=" + id + ", name=" + name + "]";
}
}
搜索服务实施
@Service("simpleSolutionSearchService")
@Transactional
public class SimpleSolutionSearchServiceImpl implements SimpleSolutionSearchService {
@Autowired
private SessionFactory sessionFactory;
// This works fine
public List<Solution> findSolutions() {
Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Solution.class);
// Hibernate should coalesce the results, yielding only solutions
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}
// This throws
public List<Solution> findSolutionsWithTags(String[] requiredTags) {
final String parentAlias = "sol";
final String collFieldAlias = "t";
final String tagValueField = collFieldAlias + ".name";
DetachedCriteria subquery = DetachedCriteria.forClass(Solution.class)
.add(Restrictions.eqProperty("id", parentAlias + ".id"))
.createAlias("tags", collFieldAlias) //
.add(Restrictions.in(tagValueField, requiredTags)) //
.setProjection(Projections.count(tagValueField));
Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Solution.class, parentAlias)
.add(Subqueries.eq((long) requiredTags.length, subquery));
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}
}
解决方案库
public interface SimpleSolutionRepository extends CrudRepository<Solution, Long> {
}
标签库
public interface SimpleTagRepository extends CrudRepository<Tag, Long> {
}
测试用例
@RunWith(SpringRunner.class)
@SpringBootTest
public class SolutionServiceTest {
private static final Logger logger = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
@Autowired
private SimpleSolutionRepository solutionRepository;
@Autowired
private SimpleTagRepository tagRepository;
@Autowired
private SimpleSolutionSearchService searchService;
@Test
public void testRepositories() throws Exception {
final String tagName1 = "tag name 1";
final String tagName2 = "tag name 2";
Tag t1 = new Tag();
t1.setName(tagName1);
t1 = tagRepository.save(t1);
Assert.assertNotNull(t1.getId());
logger.info("Created tag {}", t1);
Tag t2 = new Tag();
t2.setName(tagName2);
t2 = tagRepository.save(t2);
Assert.assertNotNull(t2.getId());
logger.info("Created tag {}", t2);
Solution s1 = new Solution();
s1.setName("solution one tag");
s1.getTags().add(t1);
s1 = solutionRepository.save(s1);
Assert.assertNotNull(s1.getId());
logger.info("Created solution {}", s1);
Solution s2 = new Solution();
s2.setName("solution two tags");
s2.getTags().add(t1);
s2.getTags().add(t2);
s2 = solutionRepository.save(s2);
Assert.assertNotNull(s2.getId());
logger.info("Created solution {}", s1);
List<Solution> sols = searchService.findSolutions();
Assert.assertTrue(sols.size() == 2);
for (Solution s : sols)
logger.info("Found solution {}", s);
String[] searchTags = { tagName1, tagName2 };
List<Solution> taggedSols = searchService.findSolutionsWithTags(searchTags);
// EXPECT ONE OBJECT BUT GET ZERO
Assert.assertTrue(taggedSols.size() == 1);
}
}
Restrictions.eq is for compare property with a value, Restrictions.propertyEq 将 属性 与另一个 属性 进行比较。因此，代码将 parentAlias + ".id" 视为字符串值以与 ID 属性 进行比较，而不是父 ID 属性，这导致 ClassCaseException。
没有找到记录的问题，where this_.ID=this_.ID说出原因。 Hibernate 认为子查询中的 id 属性 引用父查询 Solution，而不是子查询 Solution。在这种情况下，应向子查询提供别名以区分 id 属性。
public List<Solution> findSolutionsWithTags(String[] requiredTags) {
final String parentAlias = "sol";
final String childAlias = "subSol";
final String collFieldAlias = "t";
final String tagValueField = collFieldAlias + ".name";
DetachedCriteria subquery = DetachedCriteria.forClass(Solution.class, childAlias)
// Throws ClassCastException; apparently sol.id isn't replaced with an ID value?
// Problem should be due to following line
//.add(Restrictions.eq("id", parentAlias + ".id"))
// Use eqProperty instead
.add(Restrictions.eqProperty(childAlias + ".id", parentAlias + ".id"))
.createAlias("tags", collFieldAlias) //
.add(Restrictions.in(tagValueField, requiredTags)) //
.setProjection(Projections.count(tagValueField));
Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Solution.class, parentAlias)
.add(Subqueries.eq((long) requiredTags.length, subquery));
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}