NewbieGuideToOJB2

Page title (cookbook approach, tutorial , ...)

- TARGET-AUDIENCE: *beginner* advanced expert
- COCOON-RELEASES: 2.0.3, 2.0.4
- DOCUMENT-STATUS: *draft* reviewed released

===Introduction===

This is copy&paste from http://joose.iki.fi/ojb/

This page is my setup and adventure to get cforms work with OJB and 1:n relationships. After all this is working, this could be used as a template to create tutorial / something to help others to do the same thing.

Status

OJB stuff seems to work ok, because the test-script executes ok.

UPDATE works when I added hidden field with id see template.

DELETE works.

Everything is working

TODO

Database

CREATE TABLE parent (

• id SERIAL, name VARCHAR(50),

PRIMARY KEY (id));

CREATE TABLE childs (

• id SERIAL, parent_id INTEGER NOT NULL, name VARCHAR(20),

PRIMARY KEY(id), FOREIGN KEY(parent_id) REFERENCES parent (id));

So we have one-to-many (1:n) connection between parent and child.

So if we add new records, we first have to add record to table A and afterthat records to table childs.

Java classes

parent

package net.vettenranta;

import java.util.ArrayList; import java.util.Collection;

import java.io.Serializable;

public class Parent implements Serializable {

• private int id;

  private Collection childs = new ArrayList (); private String name; public int getId () { return id; } public void setId (int id) { this.id = id; } public Collection getChilds () { return childs; } public void setChilds (Collection childs ) { this.childs = childs; } public void addChild (Child child) {

  • child.setParent (this); this.childs.add (child);
  } public String getName () { return name; } public void setName (String name) { this.name = name; }

}

child

package net.vettenranta;

import java.io.Serializable;

public class Child implements Serializable {

• private int id; private Parent parent; private String name; public int getId () { return id; } public void setId (int id) { this.id = id; } public Parent getParent () { return parent; } public void setParent (Parent parent) { this.parent = parent; } public String getName () { return name; } public void setName (String name) { this.name = name; }

}

DAO

package net.vettenranta;

import java.util.Iterator;

import javax.jdo.PersistenceManager; import javax.jdo.Transaction;

import org.apache.cocoon.ojb.jdo.components.JdoPMF; import org.apache.ojb.broker.Identity; import org.apache.ojb.broker.PersistenceBroker; import org.apache.ojb.broker.PersistenceBrokerFactory; import org.apache.ojb.broker.util.ObjectModificationDefaultImpl;

public class DAO {

• // requires lot's of comments public Parent retrieve(Parent bean, JdoPMF pmf) {

  • PersistenceManager persistenceManager = pmf.getPersistenceManager(); PersistenceBroker broker = PersistenceBrokerFactory.defaultPersistenceBroker(); Query query = new QueryByIdentity(bean); Parent result = (Parent) broker.getObjectByQuery(query); broker.close(); return result;

  } public void insert(Parent bean, JdoPMF pmf) {

  • PersistenceManager persistenceManager = pmf.getPersistenceManager(); PersistenceBroker broker = PersistenceBrokerFactory.defaultPersistenceBroker(); broker.beginTransaction(); broker.store(bean); broker.commitTransaction(); broker.close();

  } public void remove(Parent bean, JdoPMF pmf) {

  • PersistenceManager persistenceManager = pmf.getPersistenceManager(); PersistenceBroker broker = PersistenceBrokerFactory.defaultPersistenceBroker(); broker.beginTransaction(); broker.delete(bean); broker.commitTransaction(); broker.close();

  } public void update(Parent bean, JdoPMF pmf) {

  • PersistenceManager persistenceManager = pmf.getPersistenceManager(); PersistenceBroker broker = PersistenceBrokerFactory.defaultPersistenceBroker(); Iterator it = bean.getChilds().iterator(); broker.beginTransaction();

    broker.store(bean, ObjectModificationDefaultImpl.UPDATE); broker.commitTransaction(); broker.close();

  }

}

package.jdo

<?xml version="1.0"?> <!DOCTYPE jdo SYSTEM "file:/javax/jdo/jdo.dtd">

<jdo>

• <package name="net.vettenranta">

  • <class name="Parent" identity-type="datastore">

    • <field name="id" persistence-modifier="persistent">

      • <extension vendor-name="ojb" key="column" value="ID"/>

      </field> <field name="name" persistence-modifier="persistent">

      • <extension vendor-name="ojb" key="column" value="NAME"/>

      </field> <field name="childs" embedded="true">

      • <collection embedded-element="true" />

      </field>

    </class> <class name="Child" identity-type="datastore">

    • <field name="id" persistence-modifier="persistent">

      • <extension vendor-name="ojb" key="column" value="ID"/>

      </field> <field name="parent" persistence-modifier="persistent">

      • <extension vendor-name="ojb" key="column" value="PARENT_ID"/>

      </field> <field name="name" persistence-modifier="persistent">

      • <extension vendor-name="ojb" key="column" value="NAME"/>

      </field>

    </class>

  </package>

</jdo>

Enhancing the classes

I have untarred jdo to my homedirectory.

Manually

This will place enhanced binaries to output directory. It will create that directory.

$ export CLASSPATH=~/jdo-1_0_1-ri/jdo.jar:~/jdo-1_0_1-ri/jdori-enhancer.jar:~/jdo-1_0_1-ri/jdori.jar:. $ java com.sun.jdori.enhancer.Main -d output package.jdo net/vettenranta/Parent.class net/vettenranta/Child.class

repository.xml

<descriptor-repository version="1.0" isolation-level="read-uncommitted">

• <jdbc-connection-descriptor jcd-alias="test" default-connection="true" platform="PostgreSQL" subprotocol="postgresql">

  • <sequence-manager className="org.apache.ojb.broker.util.sequence.SequenceManagerNextValImpl"/>

  </jdbc-connection-descriptor> <class-descriptor class="net.vettenranta.Parent" table="PARENT">

  • <field-descriptor name="id" primarykey="true" nullable="false" default-fetch="true" autoincrement="true" column="ID" sequence-name="parent_id_seq" jdbc-type="INTEGER"/> <field-descriptor name="name" default-fetch="true" column="NAME" jdbc-type="VARCHAR"/> <collection-descriptor name="childs" element-class-ref="net.vettenranta.Child" auto-retrieve="true" auto-delete="true" auto-update="true">

    • <inverse-foreignkey field-ref="parent_id"/>

    </collection-descriptor>

  </class-descriptor> <class-descriptor class="net.vettenranta.Child" table="CHILDS">

  • <field-descriptor name="id" primarykey="true" nullable="false" default-fetch="true" column="ID" jdbc-type="INTEGER" autoincrement="true" sequence-name="childs_id_seq" /> <field-descriptor name="parent_id" nullable="false" default-fetch="true" column="PARENT_ID" jdbc-type="INTEGER" access="anonymous"/> <field-descriptor name="name" default-fetch="true" column="NAME" jdbc-type="VARCHAR"/> <reference-descriptor name="parent" class-ref="net.vettenranta.Parent">

    • <foreignkey field-ref="parent_id" />

    </reference-descriptor>

  </class-descriptor>

</descriptor-repository>

Test-script (in cocoon flowscript)

This script works. So It's pretty safe to say that everything should be ok.

function test () {

• var factory = cocoon.getComponent(Packages.org.apache.cocoon.ojb.jdo.components.JdoPMF.ROLE); var bean = new Packages.net.vettenranta.Parent (); var child; var dao = new Packages.net.vettenranta.DAO (); var id; var iterator; // 1. // let's make a new bean with 1 child bean.setName ('Dad 1'); child = new Packages.net.vettenranta.Child (); child.setName ('Child 1'); bean.addChild (child); // 2. // let's save it dao.insert (bean, factory); // 3. // let's retrieve it from database id = bean.getId(); bean = new Packages.net.vettenranta.Parent (); bean.setId(id); bean = dao.retrieve(bean, factory); iterator=bean.getChilds().iterator(); while (iterator.hasNext()) {
  • child = iterator.next(); child.setName ('Child XXX');
  } // 4. // let's modify the bean bean.setName ('Dad 2'); child = new Packages.net.vettenranta.Child (); child.setName ('Child 2'); bean.addChild (child); // let's save it to the database dao.update (bean, factory); // and remove it from database dao.remove (bean, factory); cocoon.releaseComponent(factory); cocoon.redirectTo ("add.html");

}

CForms flowscript

• bean.setId (id); bean = dao.retrieve (bean, factory); form.load(bean); form.showForm("forms/edit.html"); // EVERYTHING OK SO FAR form.save(bean); dao.update (bean, factory);

CForms binding

<fb:context xmlns:fb="http://apache.org/cocoon/forms/1.0#binding" path="/" >

• <fb:value id="id" path="id" direction="load"/> <fb:value id="name" path="name" />

  • <fb:repeater id="childs"

    • parent-path="."

      row-path="childs">

    • <fb:identity>

      • <fb:value id="id" path="@id"/>

      </fb:identity>

      <fb:on-bind>

      • <fb:value id="id" path="id"/> <fb:value id="name" path="name"/>

      </fb:on-bind>

      <fb:unique-row>

      • <fb:unique-field id="id" path="id"/>

      </fb:unique-row>

      <fb:on-delete-row>

      • <fb:delete-node />

      </fb:on-delete-row>

      <fb:on-insert-row>

      • <fb:insert-bean

        • classname="net.vettenranta.Child"

          addmethod="addChild"/>

      </fb:on-insert-row>

    </fb:repeater>

</fb:context>

CForms forms

<fd:form

• xmlns:fd="http://apache.org/cocoon/forms/1.0#definition" xmlns:i18n="http://apache.org/cocoon/i18n/2.1">

• <fd:widgets>

  • <fd:field id="id">

    • <fd:datatype base="integer" />

    </fd:field> <fd:field id="name">

    • <fd:datatype base="string" /> <fd:label>Name</fd:label />

    </fd:field>

    <fd:repeater id="childs">

    • <fd:widgets>

      <fd:field id="id">

      • <fd:datatype base="integer" />

      </fd:field>

      • <fd:field id="name" required="true">

        • <fd:datatype base="string">

          • <fd:validation>

            • <fd:length min="3"/>

            </fd:validation>

          </fd:datatype> <fd:label>Name</fd:label>

        </fd:field>

        <fd:booleanfield id="select">

        • <fd:label>Select</fd:label>

        </fd:booleanfield>

      </fd:widgets>

    </fd:repeater> <fd:repeater-action id="addchild" action-command="add-row" repeater="childs">

    • <fd:label>New child</fd:label>

    </fd:repeater-action>

    <fd:repeater-action id="removechild" action-command="delete-rows" repeater="childs" select="select">

    • <fd:label>Remove child</fd:label>

    </fd:repeater-action>

  </fd:widgets>

</fd:form>

CForms template

CForms template file has to have (in row-repeater) <fi:widget id="id"><fi:styling type="hidden"><fi:widget>

Software

ojb 1.0.rc6 jdo 1.0.1-ri (sun) IBM Java2 1.4.1 Cocoon 2.1.5.1 Postgresql 7.3.4-3.rhl9 postgresql-jdbc-7.3.4-3.rhl9 redhat 9

page metadata

- AUTHOR: JooseVettenranta
- AUTHOR-CONTACT: mailto:joose@iki.fi[[BR]] - REVIEWED-BY:[[BR]] - REVIEWER-CONTACT:[[BR]]