1 Reply Latest reply on Mar 17, 2006 10:43 AM by tterm

    EntiyBean and auto-increment

    modendahl
    modendahl Mar 17, 2006 3:09 AM

      Hi,

      after reading a lot of stuff about the item. I don't know what is the
      right way.
      Here is my problem.
      I'm using Jboss 4.0.3 with a MySQL 4.1 with tables which use
      the serial type as primary key.
      I want to use entity beans which make use of the auto-increment feature.
      I'm using xdoclet. Before I start I want to know which is the right way.
      These are the things I found.
      1. Solution
      In the head of the bean

       * @jboss.entity-command name="mysql-get-generated-keys"
 *
 * @jboss.unknown-pk class="java.lang.Integer"
 * auto-increment="true"

      Do I have do declare the column of the table with the primary key
      as field in the bean?

      The create method looks like 
      /**
 * @ejb.create-method
 * @return Primary Key
 * @throws CreateException
 */
 public Integer ejbCreate() throws CreateException {
 return null;
 }

 public void ejbPostCreate() {

 }


      2. Solution
      I only declare in the head of the bean the following 
       * @jboss.entity-command name="mysql-get-generated-keys"
 *


      And the method declaration for the primary key is 
       /**
 * Getter for CMP Field id
 *
 * @ejb.pk-field
 * @ejb.persistent-field
 * @ejb.interface-method view-type="both"
 *
 * @jboss.persistence auto-increment="true"
 *
 */
 public abstract java.lan.Integer getId();

      The create method looks the same as in solution 1.

      What is the right way?

      Another problem is how can I access the bean when the key is
      autogenerated? The create method delivers a null.
      How can I access the generated key?

      Thanks in advance,

      Marcel.

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        • 1. Re: EntiyBean and auto-increment
          tterm
          tterm Mar 17, 2006 10:43 AM (in response to modendahl)

          Hello,

          this is a possible solution for me:

          /**
 * @ejb.bean name="Example"
 * display-name="Name for Example"
 * description="Description for Example"
 * jndi-name="ejb/Example"
 * type="CMP"
 * cmp-version="2.x"
 * view-type="local"
 * primkey-field = "autoIncField"
 *
 * @ejb.pk class = "java.lang.Integer" generate = "false"
 *
 * @jboss.unknown-pk class = "java.lang.Integer"
 * column-name = "autoIncField"
 * jdbc-type = "INTEGER"
 * sql-type = "INTEGER"
 * auto-increment = "true"
 *
 *
 * @jboss.entity-command name = "mysql-get-generated-keys"
 * class = "org.jboss.ejb.plugins.cmp.jdbc.keygen.JDBCMySQLCreateCommand"
 *
 */
public abstract class ExampleBean implements EntityBean {

 // more methods

/**
 * Getter for CMP Field autoIncField
 *
 * @ejb.pk-field
 * @ejb.persistent-field
 * @ejb.interface-method view-type="local"
 *
 * @jboss.persistence auto-increment = "true"
 *
 */
 public abstract java.lang.Integer getAutoIncField();

 /**
 * Setter for CMP Field autoIncField
 *
 *
 * @ejb.interface-method view-type="local"
 */
 public abstract void setAutoIncField(java.lang.Integer value);
}


          This works for me.

          How would you access a row in a table with a generated PK with a simple sql statement if you don't have the key value. I guess you have some other data in the row for a search criteria. I hope you know what I mean.

          Thomas

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