[SOLVED] Java, Hibernate and, @ManyToMany annotation - no results from one of Entity

I have an odd problem with relation

@ManyToMany

. In my case I had a Set as collection. The problem was my collecion of Bars element returns 0 rows. My exaples class was like this:

/**
 * Foo is NOT owner of relation
 */
class Foo {
  @ManyToMany(fetch = FetchType.LAZY, mappedBy = "foos")
  Collection bars;
}

/**
 * Bar is owner of relation
 */
class Bar {

  @OneToOne(fetch = FetchType.EAGER, mappedBy = "bar", optional = false, cascade = CascadeType.ALL)
  private RequiredFieldA requiredFieldA;

  @OneToOne(fetch = FetchType.EAGER, mappedBy = "bar", optional = false, cascade = CascadeType.ALL)
  private RequiredFieldB requiredFieldB;

  @OneToOne(fetch = FetchType.EAGER, mappedBy = "bar", optional = false, cascade = CascadeType.ALL)
  private RequiredFieldC requiredFieldC;

  @ManyToMany(fetch = FetchType.LAZY)
  @JoinTable(name = "BAR_FOO",
            joinColumns = @JoinColumn(name = "BAR_ID"),
            inverseJoinColumns = @JoinColumn(name = "FOO_ID"))
  Collection foos;

}

Solution:
1. I tried change

FetchType

from LAZY to EAGER - it works but I must save LAZY.
2. I decided to check what query Hibernate generated when

FetchType

is LAZY.

Results:
In my Bar entity I have required fields but in my Database i haven't got it. But the most odd is that hibernate generated INNER JOIN with only one (only first) field. This returns 0 rows becouse my first required field has no row in database for entity Bar.

The question is:
- Why FetchType.EAGER has no problems with required fileds?
- Why FetchType.LAZY INNER JOIN with ONLY ONE of required fileds (and join with only the first field)?