I'm having problems with JPA relationship mappings that i'm trying to create for an existing database schema. The part of the schema i'm having problems consists of 3 tables: share, filter and filter_command.

A share represents a directory tree which a crawler traverses. For each file found in the directory tree 0-n filter commands are executed (in specified order). There's 0-n filters for each share (unidirectional) and 1 filter_command per filter (unidirectional).

I'm getting the following exception when trying to run the application:

Caused by: javax.persistence.PersistenceException: org.hibernate.MappingException: broken column mapping for: cmd.id of: spider2.config.Filter


Here's the database schema description and some sample data:

CREATE TABLE share (
path VARCHAR(255),
PRIMARY KEY(path)
);

CREATE TABLE filter_command (
name VARCHAR(255) NOT NULL,
command VARCHAR(255) NOT NULL,
PRIMARY KEY(name)
);

CREATE TABLE filter (
share_path VARCHAR(255) NOT NULL,
command_name VARCHAR(255) NOT NULL,
filter_order int NOT NULL,
FOREIGN KEY(share_path) REFERENCES share(path),
FOREIGN KEY(command_name) REFERENCES filter_command(name),
PRIMARY KEY(share_path, command_name)
);

INSERT INTO share VALUES ('/etc');
INSERT INTO filter_command VALUES ('cat', '/bin/cat');
INSERT INTO filter_command VALUES ('ls', '/bin/ls');
INSERT INTO filter VALUES ('/etc', 'cat', 1);
INSERT INTO filter VALUES ('/etc', 'ls', 2);


The entity annotations look like this:

@Entity
@Table(name="share")
public class Share {
@Id
@Column(name="path")
private String path;

@OneToMany
@OrderBy("order ASC")
@JoinColumn(name="share_path", referencedColumnName="path")
private Collection<Filter> filters;
}

@Entity
@IdClass(FilterPK.class)
@Table(name="filter")
public class Filter {
@Id
@Column(name="share_path")
private String path;

@Id
@Column(name="command_name")
private String filter;

@Column(name="filter_order")
private int order;

@OneToOne
@JoinColumn(name="command_name", referencedColumnName="name")
private FilterCommand cmd;
}

public class FilterPK implements Serializable {
@Column(name="share_path")
public String path;

@Column(name="command_name")
public String filter;
}

@Entity
@Table(name="filter_command")
public class FilterCommand {
@Id
@Column(name="name")
private String name;

@Column(name="command")
private String command;
}

Am i doing something wrong in defining the IdClass or relationship mappings?



Here's the full exception stack trace i'm getting:

Exception in thread "main" java.lang.ExceptionInInitializerError
at spider2.Crawler.crawl(Unknown Source)
at spider2.Crawler.main(Unknown Source)
Caused by: javax.persistence.PersistenceException: org.hibernate.MappingException: broken column mapping for: cmd.id of: spider2.config.Filter
at org.hibernate.ejb.Ejb3Configuration.createEntityManagerFactory(Ejb3Configuration.java:217)
at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:114)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:37)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:27)
at spider2.config.SpiderConfig.readConfig(Unknown Source)
at spider2.config.SpiderConfig.<init>(Unknown Source)
at spider2.config.SpiderConfig.<clinit>(Unknown Source)
... 2 more
Caused by: org.hibernate.MappingException: broken column mapping for: cmd.id of: spider2.config.Filter
at org.hibernate.persister.entity.AbstractPropertyMapping.initPropertyPaths(AbstractPropertyMapping.java:122)
at org.hibernate.persister.entity.AbstractPropertyMapping.initIdentifierPropertyPaths(AbstractPropertyMapping.java:176)
at org.hibernate.persister.entity.AbstractPropertyMapping.initPropertyPaths(AbstractPropertyMapping.java:160)
at org.hibernate.persister.entity.AbstractEntityPersister.initOrdinaryPropertyPaths(AbstractEntityPersister.java:1628)
at org.hibernate.persister.entity.AbstractEntityPersister.initPropertyPaths(AbstractEntityPersister.java:1656)
at org.hibernate.persister.entity.AbstractEntityPersister.postConstruct(AbstractEntityPersister.java:2699)
at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:386)
at org.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:55)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:223)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1213)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:631)
at org.hibernate.ejb.Ejb3Configuration.createEntityManagerFactory(Ejb3Configuration.java:760)
at org.hibernate.ejb.Ejb3Configuration.createFactory(Ejb3Configuration.java:151)
at org.hibernate.ejb.Ejb3Configuration.createEntityManagerFactory(Ejb3Configuration.java:205)
... 8 more

The Exception says that the problem is in FilterCommand cmd field mapping in Filter class, where you have @OneToOne annotation.

I think you should use @ManyToOne annotation, since the same FilterCommand object can be used from several Filter objects. Because FilterCommand cmd field also maps to same database column (command_name) as Id field String filter, it should not be used for inserts (insertable=false, updatable=false).

Try this one and see if it works.

The mapping you suggested seems to be working, thanks!

Glad I could help :)