java – Hibernate：org. hibernate. hql. ast. Querysyntaxexception: unexpected token

I use hibernate. I have this query:

List<Person> list = sess.createQuery("from Person").list();

With this statement, I get everyone from @ R_ 301_ 2416@. But now I just want some people

My @ r_ 301_ 2416 @ scheme:

Project < - Project_ Person - > person

So I just want a member of the project

Use @ r_ 301_ The SQL statement on 2416 @ gives me the required results:

select * from Person inner join Project_Person 
    on person_id = id 
    where project_id = 1;

So I think I can write this in Hibernate:

List<Person> list = 
    sess.createQuery(
        "from Person inner join Project_Person
             on person_id = id 
             where project_id = "+projectId).list();

But here I get a mistake:

SERVE: Servlet.service() for servlet myproject3 threw exception
org.hibernate.hql.ast.QuerySyntaxException: unexpected token: on near line 1,column 65 [from com.mydomain.myproject.domain.Person inner join Project_Person on person_id = id where project_id = 1]
 at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:54)
 at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:47)
 at org.hibernate.hql.ast.ErrorCounter.throwQueryException(ErrorCounter.java:82)
 at org.hibernate.hql.ast.QueryTranslatorImpl.parse(QueryTranslatorImpl.java:284)
 at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:182)
 at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:136)
 at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:101)
 at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:80)
 at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:124)
 at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:156)
 at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:135)
 at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1770)
 at sun.reflect.GeneratedMethodAccessor33.invoke(UnkNown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:597)
 at org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:344)
 at $Proxy26.createQuery(UnkNown Source)
 ...

Does anyone have any ideas?

Best wishes.

New error:

SERVE: Servlet.service() for servlet myproject3 threw exception
org.hibernate.QueryException: Could not resolve property: project of: com.mydomain.myproject.domain.Person [from com.mydomain.myproject.domain.Person p where p.project.id = :id]

n: M relationship:

@ManyToMany(cascade = CascadeType.ALL)
@JoinTable(name = "Project_Person",joinColumns = {@JoinColumn(name="project_id",referencedColumnName="id")},inverseJoinColumns = {@JoinColumn(name="person_id",referencedColumnName="id")}
)
private Set<Person> persons = new HashSet<Person>();


@ManyToMany(mappedBy="persons")
private Set<Project> projects = new HashSet<Project>();

Total error

Hibernate: select project0_.id as id1_,project0_.createDate as create2_1_,project0_.description as descript3_1_,project0_.name as name1_ from Project project0_ where project0_.id=1
Hibernate: select person0_.id as id0_0_,project2_.id as id1_1_,person0_.email as email0_0_,person0_.firstName as firstName0_0_,person0_.lastName as lastName0_0_,project2_.createDate as create2_1_1_,project2_.description as descript3_1_1_,project2_.name as name1_1_ from Person person0_ inner join Project_Person projects1_ on person0_.id=projects1_.person_id inner join Project project2_ on projects1_.project_id=project2_.id where project2_.id=?
15.12.2010 16:42:26 org.apache.catalina.core.ApplicationDispatcher invoke
SERVE: Servlet.service() for servlet myproject3 threw exception
java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.mydomain.myproject.domain.Person

Solution

HQL queries are written for the object model, not @ R_ 301_ 2416 @ mode

Therefore, your query depends on how the relationship between people and projects is mapped For example, in person, there is a many to one relationship with project through project attributes. The query will be as follows:

List<Person> list = sess.createQuery(
    "from Person p where p.project.id = :id")
    .setParameter("id",projectId)
    .list();

Edit: when you need a many to many relationship

select p from Person p join p.projects proj where proj.id = :id

It is not a bad practice to pass parameters through string connection, but to use setparameter()