@Entity
@DiscriminatorValue(value="0")
public class B extends A
{
	private C otherInstance = new C();

	public B() {}

	@Embedded
	@AttributeOverrides({
		@AttributeOverride(name="field1", column=@Column(name="B_FIELD_1")),
		@AttributeOverride(name="field2", column=@Column(name="B_FIELD_2"))
	})
	public C getOtherInstance()
	{
		return otherInstance;
	}
	public void setOtherInstance(C otherInstance)
	{
		this.otherInstance = otherInstance;
	}
}

@Entity
@Inheritance(strategy= InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="TYPE",
		discriminatorType=DiscriminatorType.INTEGER, length=1)
@Table(name="MY_TABLE")
public abstract class A implements Serializable
{
	
	private C cInstance = new C();

	@Embedded
	@AttributeOverrides({
		@AttributeOverride(name="field1", column=@Column(name="A_FIELD_1")),
		@AttributeOverride(name="field2", column=@Column(name="A_FIELD_2"))
	})
	public C getCInstance()
	{
		return cInstance;
	}
	public void setCInstance(C cInstance)
	{
		this.cInstance = cInstance;
	}

}

@Embeddable
public class C
{
	private int field1;
	private int field2;

	public C() {}

	public int getField1()
	{
		return field1;
	}
	public void setField1(int field1)
	{
		this.field1 = field1;
	}

	public int getField2()
	{
		return field2;
	}
	public void setField2(int field2)
	{
		this.field2 = field2;
	}
}