[RUFFIE]

I don’t know if this should be here or in Database forum, so my excuses for that in advance. I’ll try to be as clear as possible.

Mapping documents:
Component.hbm.xml:

<hibernate-mapping package="com.frontier.hibernate"> 

    <class name="Component" table="component"> 
        <id name="idComponent" column="ID_COMPONENT" type="java.lang.Integer"> 
            <generator class="native"/> 
        </id> 
  
        <property name="cdComponent" column="CD_COMPONENT" type="java.lang.String" /> 
        <property name="omschrijving" column="OMSCHRIJVING" type="java.lang.String" /> 
        <property name="langeOmschrijving" column="LANGE_OMSCHRIJVING" type="java.lang.String" /> 
        <property name="indBedragwaarde" column="IND_BEDRAGWAARDE" type="java.lang.String" /> 
        <property name="indPrint" column="IND_PRINT" type="java.lang.String" /> 
        <property name="indSubcomponent" column="IND_SUBCOMPONENT" type="java.lang.String" /> 
        <property name="rowVersion" column="ROW_VERSION" type="java.lang.Integer" /> 
    </class> 
    
</hibernate-mapping> 

Subcomponent.hbm.xml:

<hibernate-mapping package="com.frontier.hibernate"> 

    <class name="Subcomponent" table="subcomponent"> 
        <composite-id name="id" class="SubcomponentKey"> 
            <key-many-to-one name="component" column="ID_COMPONENT" class="Component"/> 
            <key-property name="idSubcomponent" column="ID_SUBCOMPONENT" type="java.lang.Integer"/> 
        </composite-id> 
  
        <property name="calcOperator" column="CALC_OPERATOR" type="java.lang.String" /> 
        <property name="rowVersion" column="ROW_VERSION" type="java.lang.Integer" /> 
    </class> 
    
</hibernate-mapping>

Name and version of the database you are using:
mySQL 4.1.7 with InnoDB Tables

My question:
I’m rather new to struts and hibernate and still building on the hibernate tutorial on your site.

I have two tables: Component with PK id_component and Subcomponent which has a composite key that consists of foreign key id_component and it’s own auto increment id_subcomponent.

First i got Component.java:

package com.frontier.hibernate; 

import java.io.Serializable; 

/** 
 * A class that represents a row in the 'component' table. 
 * This class may be customized as it is never re-generated 
 * after being created. 
 */ 
public class Component 
    extends AbstractComponent 
    implements Serializable 
{ 
    /** 
     * Simple constructor of Component instances. 
     */ 
    public Component() 
    { 
    } 

    /** 
     * Constructor of Component instances given a simple primary key. 
     * @param idComponent 
     */ 
    public Component(java.lang.Integer idComponent) 
    { 
        super(idComponent); 
    } 

    /* Add customized code below */ 

} 

Then Subcomponent.java:

package com.frontier.hibernate; 

import java.io.Serializable; 

/** 
 * A class that represents a row in the 'subcomponent' table. 
 * This class may be customized as it is never re-generated 
 * after being created. 
 */ 
public class Subcomponent 
    extends AbstractSubcomponent 
    implements Serializable 
{ 
    /** 
     * Simple constructor of Subcomponent instances. 
     */ 
    public Subcomponent() 
    { 
    } 

    /** 
     * Constructor of Subcomponent instances given a composite primary key. 
     * @param id 
     */ 
    public Subcomponent(SubcomponentKey id) 
    { 
        super(id); 
    } 

    /* Add customized code below */ 

} 

Now SubComponentKey.java (the composite class):

/*
 * WARNING: DO NOT EDIT THIS FILE. This is a generated file that is synchronized
 * by MyEclipse Hibernate tool integration.
 *
 * Created Wed Oct 27 11:06:00 GMT-03:00 2004 by MyEclipse Hibernate Tool.
 */
package com.frontier.hibernate;

import java.io.Serializable;

/**
 * A class representing a composite primary key id for the subcomponent
 * table.  This object should only be instantiated for use with instances 
 * of the Subcomponent class.
 */
public class SubcomponentKey
    implements Serializable
{
    /** The cached hash code value for this instance.  Settting to 0 triggers re-calculation. */
    private volatile int hashValue = 0;

    /** The value of the ID_COMPONENT component of this composite id. */
    private Component component;

    /** The value of the ID_SUBCOMPONENT component of this composite id. */
    private java.lang.Integer idSubcomponent;

    /**
     * Simple constructor of SubcomponentKey instances.
     */
    public SubcomponentKey()
    {
    }

    /**
     * Returns the value of the component property.
     * @return Component
     */
    public Component getComponent()
    {
        return component;
    }

    /**
     * Sets the value of the component property.
     * @param component
     */
    public void setComponent(Component component)
    {
        hashValue = 0;
        this.component = component;
    }

    /**
     * Returns the value of the idSubcomponent property.
     * @return java.lang.Integer
     */
    public java.lang.Integer getIdSubcomponent()
    {
        return idSubcomponent;
    }

    /**
     * Sets the value of the idSubcomponent property.
     * @param idSubcomponent
     */
    public void setIdSubcomponent(java.lang.Integer idSubcomponent)
    {
        hashValue = 0;
        this.idSubcomponent = idSubcomponent;
    }

    /**
     * Implementation of the equals comparison on the basis of equality of the id components.
     * @param rhs
     * @return boolean
     */
    public boolean equals(Object rhs)
    {
        if (rhs == null)
            return false;
        if (! (rhs instanceof SubcomponentKey))
            return false;
        SubcomponentKey that = (SubcomponentKey) rhs;
        if (this.getComponent() != null && that.getComponent() != null)
        {
            if (! this.getComponent().equals(that.getComponent()))
            {
                return false;
            }
        }
        if (this.getIdSubcomponent() != null && that.getIdSubcomponent() != null)
        {
            if (! this.getIdSubcomponent().equals(that.getIdSubcomponent()))
            {
                return false;
            }
        }
        return true;
    }

    /**
     * Implementation of the hashCode method conforming to the Bloch pattern with
     * the exception of array properties (these are very unlikely primary key types).
     * @return int
     */
    public int hashCode()
    {
        if (this.hashValue == 0)
        {
            int result = 17;
            int componentValue = this.getComponent() == null ? 0 : this.getComponent().hashCode();
            result = result * 37 + componentValue;
            int idSubcomponentValue = this.getIdSubcomponent() == null ? 0 : this.getIdSubcomponent().hashCode();
            result = result * 37 + idSubcomponentValue;
            this.hashValue = result;
        }
        return this.hashValue;
    }
}

This is my interface class ComponentService.java, I’m just gonna put the Add (insert) method. It isn’t really correct like this. It’s something I just tried, without the subcomponent handlings (only component thus) it works:

public void addComponent(Component data, Subcomponent subdata) 
   { 
      Session session = null; 
       
      try 
      { 
         session = HibernateUtil.getSession(); 
         HibernateUtil.beginTransaction(); 
         session.save(data); 
         session.save(subdata); 
         HibernateUtil.commitTransaction(); 
         session.flush(); 
      } 
      catch (HibernateException e) 
      { 
         System.err.println("Hibernate Exception" + e.getMessage()); 
         throw new RuntimeException(e); 
      } 
            finally 
      { 
         if (session != null) 
         { 
            HibernateUtil.closeSession(); 

         } 
      } 

   } 

And this is the execute from my action class: 

public ActionForward execute( 
      ActionMapping mapping, 
      ActionForm form, 
      HttpServletRequest request, 
      HttpServletResponse response) { 
      ComponentForm AddComponentForm = (ComponentForm) form; 
       
      if (AddComponentForm.getOmschrijving() != null) 
      { 
         Component component = new Component(); 
         component.setCdComponent(AddComponentForm.getCdComponent()); 
         component.setOmschrijving(AddComponentForm.getOmschrijving()); 
         component.setLangeOmschrijving(AddComponentForm.getLangeOmschrijving()); 
         component.setIndBedragwaarde(AddComponentForm.getIndBedragwaarde()); 
         component.setIndPrint(AddComponentForm.getIndPrint()); 
         component.setIndSubcomponent(AddComponentForm.getIndSubcomponent()); 
         ComponentService.getInstance().addComponent(component); 
         AddComponentForm.clear(); 
      } 

I have a ComponentForm.java with the getters and setters and tried to declare SubcomponetKey idSubcomponent; and put a setter for that, but I dunno..

I’ve read the hibernate docs about composite id’s and components (chapter 7 i believe), but either I’m experiencing a blackout or i’m a real n00b.

I just want to fill in my form to add a component, and when it’s a subcomponent insert the idSubcomponent (i got a checkbox in the form to indicate that) in the Subcomponent table and get the associated idComponent (FK) with it and store it also in the Subcomponent table.

For example. I insert a component with code 01.
This component has a subcomponent which i give 01A. By clicking the checkbox indicating that this is a subcomponent, it should insert everything in the component table like this was a component, BUT insert the calc_operator, the foreign key of id_component and set the id_subcomponent (auto increment) in the subcomponent table.
It’s like parent-child, class-subclass, you get the idea 🙂

Any idea how that can be done in a simple way?

[Riyad Kalla]

Is this a software development question or a “MyEclipse” question?

[RUFFIE]

@support-rkalla wrote:

Is this a software development question or a “MyEclipse” question?

Uhm..software development…that’s why i thought i should post it here.. 😉

[Riyad Kalla]

Ohh ok, I’ll move it (Off Topic -> Software dev). This is a bit confusing, but we try and separate questions related to MyEclipse and other questions.

[dervre]

This message has not been recovered.

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