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How to handle the combination sleeping key

My hbm.xml file looks like this:

<hibernate-mapping>
<class name="pojopackage.WordhelperWordusage" table="WORDHELPER_WORDUSAGE" schema="SOZANA">
    <composite-id name="id" class="pojopackage.WordhelperWordusageId">
        <key-property name="idwh" type="java.lang.Integer">
            <column name="IDWH" />
        </key-property>
        <key-property name="idwu" type="java.lang.Integer">
            <column name="IDWU" />
        </key-property>
        <key-property name="type" type="java.lang.Integer">
            <column name="TYPE" />
        </key-property>
    </composite-id>
    <many-to-one name="wordhelper" class="pojopackage.Wordhelper" update="false" insert="false" fetch="select">
        <column name="IDWH" />
    </many-to-one>
    <many-to-one name="wordusage" class="pojopackage.Wordusage" update="false" insert="false" fetch="select">
        <column name="IDWU" />
    </many-to-one>
</class>

But I have two POJO classes that are "WordhelperWordusage.java" and "WordhelperWordusageId.java", so I'm confused, how do I handle these classes? How to implement? Thank you in advance! Update

I liked it

wordhelper_wordusage.save(wordhelper);
wordhelper_wordusage.save(wordusage);
session.save(wordhelper);
session.save(wordusage);
session.save(wordhelper_wordusage);

But this gives me such an exception:

Hibernate: select max(ID) from SOZANA.WORDFORM
Hibernate: select max(ID) from SOZANA.WORDHELPER
Exception in thread "main" org.hibernate.id.IdentifierGenerationException:
ids for this   class must be manually assigned before calling save():   pojopackage.WordhelperWordusage

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3 answers

PK, Hibernate . , . , PK, PK WordhelperWordusage, class <composite-id> ( ). . : .

, , ?

package pojopackage;

public class WordhelperWordusage { 

    private WordhelperWordusageId id;
    private Wordhelper wordhelper;
    private Wordusage wordusge;

    // Getters / Setters

    // Implement equals() and hashCode() delegating to id
}


package pojopackage;

public class WordhelperWordusageId { 
    private Integer idwu;
    private Integer type;

    // Getters / setters

    // Implement equals() and hashCode() consistently, using idwu and type.

}

hashCode() equals() . - WordhelperWordusage - id, , . id Integer equals().

+2

WordhelperWordusageId.java . idwh idwu. . Hibernate equals hashCode. WordhelperWordusage.java. id, , , , , ID. .

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