| <html><head> |
| <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> |
| <title>6. PersistenceUnitUtil</title><link rel="stylesheet" href="css/docbook.css" type="text/css"><base href="display"><meta name="generator" content="DocBook XSL Stylesheets V1.72.0"><link rel="start" href="manual.html" title="Apache OpenJPA 2.1 User's Guide"><link rel="up" href="jpa_overview_emfactory.html" title="Chapter 7. EntityManagerFactory"><link rel="prev" href="jpa_overview_emfactory_close.html" title="5. Closing the EntityManagerFactory"><link rel="next" href="jpa_overview_em.html" title="Chapter 8. EntityManager"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">6. |
| PersistenceUnitUtil |
| </th></tr><tr><td width="20%" align="left"><a accesskey="p" href="jpa_overview_emfactory_close.html">Prev</a> </td><th width="60%" align="center">Chapter 7. |
| EntityManagerFactory |
| </th><td width="20%" align="right"> <a accesskey="n" href="jpa_overview_em.html">Next</a></td></tr></table><hr></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="jpa_overview_emfactory_puutil"></a>6. |
| PersistenceUnitUtil |
| </h2></div></div></div><a class="indexterm" name="d0e4776"></a><pre class="programlisting"> |
| public PersistenceUnitUtil getPersistenceUnitUtil(); |
| </pre><p> |
| The <code class="classname">EntityManagerFactory</code> method |
| <code class="methodname">getPersistenceUnitUtil</code> to provide access to a |
| <code class="classname">PersistenceUnitUtil</code> utility. <code class="classname">PersistenceUnitUtil</code> |
| can be used to obtain the identity of a managed object and determine the load |
| state of the entity or one of its attributes. If the object is not |
| managed by one of the entity managers created from the entity manager factory |
| from which the utility was obtained, the <code class="methodname">getIdentifier</code> method will |
| return null and the <code class="methodname">isLoaded</code> methods will return false. |
| </p><pre class="programlisting"> |
| EntityManagerFactory emf = Persistence.createEntityManagerFactory(); |
| PersistenceUnitUtil puUtil = emf.getPersistenceUnitUtil(); |
| |
| if (puUtil.getIdentifier(deptEntity) == null) { |
| throw new Exception("Identity is not valid."); |
| } |
| if (!puUtil.isLoaded(deptEntity, "employees")) { |
| throw new Exception("Employees not loaded.") |
| } |
| </pre><p> |
| </p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="jpa_overview_emfactory_close.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="jpa_overview_emfactory.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="jpa_overview_em.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">5. |
| Closing the EntityManagerFactory |
| </td><td width="20%" align="center"><a accesskey="h" href="manual.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 8. |
| EntityManager |
| </td></tr></table></div></body></html> |