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From awh...@apache.org
Subject svn commit: r434517 [10/23] - in /incubator/openjpa/trunk: openjpa-kernel/src/main/java/org/apache/openjpa/meta/ openjpa-lib/src/main/java/org/apache/openjpa/lib/meta/ openjpa-project/src/doc/manual/
Date Thu, 24 Aug 2006 20:41:14 GMT
Modified: incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_overview_why.xml
URL: http://svn.apache.org/viewvc/incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_overview_why.xml?rev=434517&r1=434516&r2=434517&view=diff
==============================================================================
--- incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_overview_why.xml (original)
+++ incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_overview_why.xml Thu Aug 24 13:41:12 2006
@@ -1,371 +1,665 @@
-
-    <chapter id="jpa_overview_why">
-      <title>Why JPA?</title>
-      <indexterm zone="jpa_overview_why">
-        <primary>JPA</primary>
-        <secondary>why</secondary>
-      </indexterm>
-      <para>
-  Java developers who need to store and retrieve persistent 
-  data already have several options available to them:
-  serialization, JDBC, JDO, proprietary object-relational mapping tools, 
-  object databases, and EJB 2 entity beans.  Why introduce yet   
-  another persistence framework?  The answer to this question is that with
-  the exception of JDO, each of the aforementioned persistence solutions
-  has severe limitations.  JPA attempts to overcome these
-  limitations, as illustrated by the table below.
-  </para>
-      <table tocentry="1">
-        <title>Persistence Mechanisms</title>
+<chapter id="jpa_overview_why">
+    <title>
+        Why JPA?
+    </title>
+    <indexterm zone="jpa_overview_why">
+        <primary>
+            JPA
+        </primary>
+        <secondary>
+            why
+        </secondary>
+    </indexterm>
+    <para>
+Java developers who need to store and retrieve persistent data already have
+several options available to them: serialization, JDBC, JDO, proprietary
+object-relational mapping tools, object databases, and EJB 2 entity beans. Why
+introduce yet another persistence framework? The answer to this question is that
+with the exception of JDO, each of the aforementioned persistence solutions has
+severe limitations. JPA attempts to overcome these limitations, as illustrated
+by the table below.
+    </para>
+    <table tocentry="1">
+        <title>
+            Persistence Mechanisms
+        </title>
         <tgroup cols="8" align="left" colsep="1" rowsep="1">
-          <colspec colname="sup"/>
-          <colspec colname="ser"/>
-          <colspec colname="jdbc"/>
-          <colspec colname="or"/>
-          <colspec colname="objdb"/>
-          <colspec colname="ejb2"/>
-          <colspec colname="jdo"/>
-          <colspec colname="ejb3"/>
-          <thead>
-            <row>
-              <entry colname="sup">Supports:</entry>
-              <entry colname="ser">Serialization</entry>
-              <entry colname="jdbc">JDBC</entry>
-              <entry colname="or">ORM</entry>
-              <entry colname="objdb">ODB</entry>
-              <entry colname="ejb2">EJB 2</entry>
-              <entry colname="jdo">JDO</entry>
-              <entry colname="ejb3">JPA</entry>
-            </row>
-          </thead>
-          <tbody>
-            <row>
-              <entry colname="sup">Java Objects</entry>
-              <entry colname="ser">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdbc">No</entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Advanced OO Concepts</entry>
-              <entry colname="ser">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdbc">No</entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">No</entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Transactional Integrity</entry>
-              <entry colname="ser">No</entry>
-              <entry colname="jdbc">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Concurrency</entry>
-              <entry colname="ser">No</entry>
-              <entry colname="jdbc">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Large Data Sets</entry>
-              <entry colname="ser">No</entry>
-              <entry colname="jdbc">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Existing Schema</entry>
-              <entry colname="ser">No</entry>
-              <entry colname="jdbc">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">No</entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">
+            <colspec colname="sup">
+            </colspec>
+            <colspec colname="ser">
+            </colspec>
+            <colspec colname="jdbc">
+            </colspec>
+            <colspec colname="or">
+            </colspec>
+            <colspec colname="objdb">
+            </colspec>
+            <colspec colname="ejb2">
+            </colspec>
+            <colspec colname="jdo">
+            </colspec>
+            <colspec colname="jpa">
+            </colspec>
+            <thead>
+                <row>
+                    <entry colname="sup">
+                        Supports:
+                    </entry>
+                    <entry colname="ser">
+                        Serialization
+                    </entry>
+                    <entry colname="jdbc">
+                        JDBC
+                    </entry>
+                    <entry colname="or">
+                        ORM
+                    </entry>
+                    <entry colname="objdb">
+                        ODB
+                    </entry>
+                    <entry colname="ejb2">
+                        EJB 2
+                    </entry>
+                    <entry colname="jdo">
+                        JDO
+                    </entry>
+                    <entry colname="jpa">
+                        JPA
+                    </entry>
+                </row>
+            </thead>
+            <tbody>
+                <row>
+                    <entry colname="sup">
+                        Java Objects
+                    </entry>
+                    <entry colname="ser">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdbc">
+                        No
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Advanced OO Concepts
+                    </entry>
+                    <entry colname="ser">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdbc">
+                        No
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        No
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Transactional Integrity
+                    </entry>
+                    <entry colname="ser">
+                        No
+                    </entry>
+                    <entry colname="jdbc">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Concurrency
+                    </entry>
+                    <entry colname="ser">
+                        No
+                    </entry>
+                    <entry colname="jdbc">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Large Data Sets
+                    </entry>
+                    <entry colname="ser">
+                        No
+                    </entry>
+                    <entry colname="jdbc">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Existing Schema
+                    </entry>
+                    <entry colname="ser">
+                        No
+                    </entry>
+                    <entry colname="jdbc">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        No
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        
             Relational and Non-Relational Stores
-          </entry>
-              <entry colname="ser">No</entry>
-              <entry colname="jdbc">No</entry>
-              <entry colname="or">No</entry>
-              <entry colname="objdb">No</entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">No</entry>
-            </row>
-            <row>
-              <entry colname="sup">Queries</entry>
-              <entry colname="ser">No</entry>
-              <entry colname="jdbc">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Strict Standards / Portability</entry>
-              <entry colname="ser">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdbc">No</entry>
-              <entry colname="or">No</entry>
-              <entry colname="objdb">No</entry>
-              <entry colname="ejb2">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-            <row>
-              <entry colname="sup">Simplicity</entry>
-              <entry colname="ser">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="jdbc">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="or">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="objdb">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb2">No</entry>
-              <entry colname="jdo">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-              <entry colname="ejb3">
-                <emphasis role="bold">Yes</emphasis>
-              </entry>
-            </row>
-          </tbody>
+          
+                    </entry>
+                    <entry colname="ser">
+                        No
+                    </entry>
+                    <entry colname="jdbc">
+                        No
+                    </entry>
+                    <entry colname="or">
+                        No
+                    </entry>
+                    <entry colname="objdb">
+                        No
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        No
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Queries
+                    </entry>
+                    <entry colname="ser">
+                        No
+                    </entry>
+                    <entry colname="jdbc">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Strict Standards / Portability
+                    </entry>
+                    <entry colname="ser">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdbc">
+                        No
+                    </entry>
+                    <entry colname="or">
+                        No
+                    </entry>
+                    <entry colname="objdb">
+                        No
+                    </entry>
+                    <entry colname="ejb2">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+                <row>
+                    <entry colname="sup">
+                        Simplicity
+                    </entry>
+                    <entry colname="ser">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jdbc">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="or">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="objdb">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="ejb2">
+                        No
+                    </entry>
+                    <entry colname="jdo">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                    <entry colname="jpa">
+                        <emphasis role="bold">
+                            Yes
+                        </emphasis>
+                    </entry>
+                </row>
+            </tbody>
         </tgroup>
-      </table>
-      <itemizedlist>
+    </table>
+    <itemizedlist>
         <listitem>
-          <para><indexterm><primary>serialization</primary></indexterm><indexterm><primary>JPA</primary><secondary>vs serialization</secondary></indexterm><emphasis>Serialization</emphasis> is Java's 
-      built-in mechanism for transforming an object graph into a
-      series of bytes, which can then be sent over the network or
-      stored in a file.  Serialization is very easy to use, 
-      but it is also very limited.  It must store and retrieve the
-      entire object graph at once, making it unsuitable for
-      dealing with large amounts of data.  It cannot undo changes 
-      that are made to objects if an error occurs while updating
-      information, making it unsuitable for applications that 
-      require strict data integrity.  Multiple threads or programs
-      cannot read and write the same serialized data concurrently
-      without conflicting with each other.  It provides no query
-      capabilities.  All these factors make serialization useless 
-      for all but the most trivial persistence needs.
-      </para>
+            <para>
+            <indexterm>
+                <primary>
+                    serialization
+                </primary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JPA
+                </primary>
+                <secondary>
+                    vs serialization
+                </secondary>
+            </indexterm>
+<emphasis>Serialization</emphasis> is Java's built-in mechanism for transforming
+an object graph into a series of bytes, which can then be sent over the network
+or stored in a file. Serialization is very easy to use, but it is also very
+limited. It must store and retrieve the entire object graph at once, making it
+unsuitable for dealing with large amounts of data. It cannot undo changes that
+are made to objects if an error occurs while updating information, making it
+unsuitable for applications that require strict data integrity. Multiple threads
+or programs cannot read and write the same serialized data concurrently without
+conflicting with each other. It provides no query capabilities. All these
+factors make serialization useless for all but the most trivial persistence
+needs.
+            </para>
         </listitem>
         <listitem>
-          <para><indexterm><primary>Java Database Connectivity</primary><see>JDBC</see></indexterm><indexterm><primary>JDBC</primary></indexterm><indexterm><primary>JPA</primary><secondary>vs JDBC</secondary></indexterm>
-      Many developers use the 
-      <emphasis>Java Database Connectivity</emphasis> (JDBC) APIs to
-      manipulate persistent data in relational databases.  JDBC 
-      overcomes most of the shortcomings of serialization:
-      it can handle large amounts of data, has mechanisms to ensure
-      data integrity, supports concurrent access to information, and 
-      has a sophisticated query language in SQL.  Unfortunately, JDBC
-      does not duplicate serialization's ease of use.  The relational
-      paradigm used by JDBC was not designed for storing objects,
-      and therefore forces you to either abandon
-      object-oriented programming for the portions of your code 
-      that deal with persistent data, or to find a way of mapping 
-      object-oriented concepts like inheritance to relational 
-      databases yourself.  
-      </para>
+            <para>
+            <indexterm>
+                <primary>
+                    Java Database Connectivity
+                </primary>
+                <see>
+                    JDBC
+                </see>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JDBC
+                </primary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JPA
+                </primary>
+                <secondary>
+                    vs JDBC
+                </secondary>
+            </indexterm>
+Many developers use the <emphasis>Java Database Connectivity</emphasis> (JDBC)
+APIs to manipulate persistent data in relational databases. JDBC overcomes most
+of the shortcomings of serialization: it can handle large amounts of data, has
+mechanisms to ensure data integrity, supports concurrent access to information,
+and has a sophisticated query language in SQL. Unfortunately, JDBC does not
+duplicate serialization's ease of use. The relational paradigm used by JDBC was
+not designed for storing objects, and therefore forces you to either abandon
+object-oriented programming for the portions of your code that deal with
+persistent data, or to find a way of mapping object-oriented concepts like
+inheritance to relational databases yourself.
+            </para>
         </listitem>
         <listitem>
-          <para><indexterm><primary>object-relational mapping</primary><see>ORM</see></indexterm><indexterm><primary>ORM</primary></indexterm><indexterm><primary>JPA</primary><secondary>vs ORM products</secondary></indexterm>
-      There are many proprietary software products that can perform the
-      mapping between objects and relational database tables for you.
-      These <emphasis>object-relational mapping</emphasis> (ORM) 
-      frameworks allow you to focus on the object model and not concern
-      yourself with the mismatch between 
-      the object-oriented and relational paradigms.  Unfortunately, 
-      each of these product has its own set of APIs.
-      Your code becomes tied to the proprietary interfaces of a single
-      vendor.  If the vendor raises prices, fails to fix show-stopping 
-      bugs, or falls behind in features, you cannot switch to another 
-      product without rewriting all of your persistence code.   This is 
-      referred to as vendor lock-in.
-      </para>
+            <para>
+            <indexterm>
+                <primary>
+                    object-relational mapping
+                </primary>
+                <see>
+                    ORM
+                </see>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    ORM
+                </primary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JPA
+                </primary>
+                <secondary>
+                    vs ORM products
+                </secondary>
+            </indexterm>
+There are many proprietary software products that can perform the mapping
+between objects and relational database tables for you. These <emphasis>
+object-relational mapping</emphasis> (ORM) frameworks allow you to focus on the
+object model and not concern yourself with the mismatch between the
+object-oriented and relational paradigms. Unfortunately, each of these product
+has its own set of APIs. Your code becomes tied to the proprietary interfaces of
+a single vendor. If the vendor raises prices, fails to fix show-stopping bugs,
+or falls behind in features, you cannot switch to another product without
+rewriting all of your persistence code. This is referred to as vendor lock-in.
+            </para>
         </listitem>
         <listitem>
-          <para><indexterm><primary>object database</primary><see>ODB</see></indexterm><indexterm><primary>ODB</primary></indexterm><indexterm><primary>JPA</primary><secondary>vs ODBs</secondary></indexterm><indexterm><primary>ODBMG</primary></indexterm>
-      Rather than map objects to relational databases, some software
-      companies have developed a form of database designed 
-      specifically to store objects.  These
-      <emphasis>object databases</emphasis> (ODBs) are often much
-      easier to use than object-relational mapping software.
-      The Object Database Management Group (ODMG) was formed to create
-      a standard API for accessing object databases; few object
-      database vendors, however, comply with the ODMG's 
-      recommendations.  Thus, vendor lock-in plagues object databases
-      as well.  Many companies are also hesitant to switch from
-      tried-and-true relational systems to the relatively unknown object
-      database technology.  Fewer data-analysis tools are available
-      for object database systems, and there are vast quantities of
-      data already stored in older relational databases.  For all of
-      these reasons and more, object databases have not caught on
-      as well as their creators hoped.
-      </para>
+            <para>
+            <indexterm>
+                <primary>
+                    object database
+                </primary>
+                <see>
+                    ODB
+                </see>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    ODB
+                </primary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JPA
+                </primary>
+                <secondary>
+                    vs ODBs
+                </secondary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    ODBMG
+                </primary>
+            </indexterm>
+Rather than map objects to relational databases, some software companies have
+developed a form of database designed specifically to store objects. These
+<emphasis>object databases</emphasis> (ODBs) are often much easier to use than
+object-relational mapping software. The Object Database Management Group (ODMG)
+was formed to create a standard API for accessing object databases; few object
+database vendors, however, comply with the ODMG's recommendations. Thus, vendor
+lock-in plagues object databases as well. Many companies are also hesitant to
+switch from tried-and-true relational systems to the relatively unknown object
+database technology. Fewer data-analysis tools are available for object database
+systems, and there are vast quantities of data already stored in older
+relational databases. For all of these reasons and more, object databases have
+not caught on as well as their creators hoped.
+            </para>
         </listitem>
         <listitem>
-          <para><indexterm><primary>Enterprise Java Beans</primary><see>EJB</see></indexterm><indexterm><primary>EJB</primary></indexterm><indexterm><primary>JPA</primary><secondary>vs EJB 2</secondary></indexterm>
-      The Enterprise Edition of the Java platform introduced entity
-      Enterprise Java Beans (EJBs).  EJB 2.x entities are components that
-      represent persistent information in a datastore.  Like 
-      object-relational mapping solutions, EJB 2.x entities provide
-      an object-oriented view of persistent data.  Unlike 
-      object-relational software, however, EJB 2.x entities are not
-      limited to relational databases; the persistent information they
-      represent may come from an Enterprise Information System (EIS) or
-      other storage device.  Also, EJB 2.x entities use a strict standard,
-      making them portable across vendors.  Unfortunately, the EJB 2.x 
-      standard is somewhat limited in the object-oriented concepts it can 
-      represent.  Advanced features like inheritance, polymorphism, and 
-      complex relations are absent.  Additionally, EBJ 2.x entities are
-      difficult to code, and they require heavyweight and often expensive
-      application servers to run.
-      </para>
+            <para>
+            <indexterm>
+                <primary>
+                    Enterprise Java Beans
+                </primary>
+                <see>
+                    EJB
+                </see>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    EJB
+                </primary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JPA
+                </primary>
+                <secondary>
+                    vs EJB 2
+                </secondary>
+            </indexterm>
+The Enterprise Edition of the Java platform introduced entity Enterprise Java
+Beans (EJBs). EJB 2.x entities are components that represent persistent
+information in a datastore. Like object-relational mapping solutions, EJB 2.x
+entities provide an object-oriented view of persistent data. Unlike
+object-relational software, however, EJB 2.x entities are not limited to
+relational databases; the persistent information they represent may come from an
+Enterprise Information System (EIS) or other storage device. Also, EJB 2.x
+entities use a strict standard, making them portable across vendors.
+Unfortunately, the EJB 2.x standard is somewhat limited in the object-oriented
+concepts it can represent. Advanced features like inheritance, polymorphism, and
+complex relations are absent. Additionally, EBJ 2.x entities are difficult to
+code, and they require heavyweight and often expensive application servers to
+run.
+            </para>
         </listitem>
         <listitem>
-          <para><indexterm><primary>JDO</primary></indexterm><indexterm><primary>JPA</primary><secondary>vs JDO</secondary></indexterm>
-      The JDO specification uses an API that is strikingly similar to
-      JPA.  JDO, however, supports non-relational databases, 
-      a feature that some argue dilutes the specification.
-      </para>
+            <para>
+            <indexterm>
+                <primary>
+                    JDO
+                </primary>
+            </indexterm>
+            <indexterm>
+                <primary>
+                    JPA
+                </primary>
+                <secondary>
+                    vs JDO
+                </secondary>
+            </indexterm>
+The JDO specification uses an API that is strikingly similar to JPA. JDO,
+however, supports non-relational databases, a feature that some argue dilutes
+the specification.
+            </para>
         </listitem>
-      </itemizedlist>
-      <para><indexterm><primary>JPA</primary></indexterm>
-  JPA combines the best features from each of the persistence 
-  mechanisms listed above.  Creating entities under JPA
-  is as simple as creating serializable classes.  JPA supports the
-  large data sets, data consistency, concurrent use, and query capabilities of
-  JDBC.  Like object-relational software and object databases, JPA
-  allows the use of advanced object-oriented concepts such as inheritance. 
-  JPA avoids vendor lock-in by relying on a strict specification
-  like JDO and EJB 2.x entities.  JPA focuses on relational 
-  databases.  And like JDO, JPA is extremely easy to use.
-  </para>
-      <note>
+    </itemizedlist>
+    <para>
+    <indexterm>
+        <primary>
+            JPA
+        </primary>
+    </indexterm>
+JPA combines the best features from each of the persistence mechanisms listed
+above. Creating entities under JPA is as simple as creating serializable
+classes. JPA supports the large data sets, data consistency, concurrent use, and
+query capabilities of JDBC. Like object-relational software and object
+databases, JPA allows the use of advanced object-oriented concepts such as
+inheritance. JPA avoids vendor lock-in by relying on a strict specification like
+JDO and EJB 2.x entities. JPA focuses on relational databases. And like JDO, JPA
+is extremely easy to use.
+    </para>
+    <note>
         <para>
-    OpenJPA typically stores data in relational databases, but can be 
-    customized for use with non-relational datastores as well.
+OpenJPA typically stores data in relational databases, but can be customized for
+use with non-relational datastores as well.
+        </para>
+    </note>
+    <para>
+JPA is not ideal for every application. For many applications, though, it
+provides an exciting alternative to other persistence mechanisms.
     </para>
-      </note>
-      <para>
-  JPA is not ideal for every application.  For many applications,
-  though, it provides an exciting alternative to other persistence mechanisms.
-  </para>
-    </chapter>
+</chapter>

Modified: incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_resources.xml
URL: http://svn.apache.org/viewvc/incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_resources.xml?rev=434517&r1=434516&r2=434517&view=diff
==============================================================================
--- incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_resources.xml (original)
+++ incubator/openjpa/trunk/openjpa-project/src/doc/manual/jpa_resources.xml Thu Aug 24 13:41:12 2006
@@ -1,39 +1,39 @@
-
-  <appendix id="jpa_resources">
-    <title>JPA Resources</title>
+<appendix id="jpa_resources">
+    <title>
+        JPA Resources
+    </title>
     <itemizedlist>
-      <listitem>
-        <para>
-          <ulink url="http://java.sun.com/aboutJava/communityprocess/jsr/jsr_220_dataobj.html">
-      EJB 3 JSR page</ulink>
-        </para>
-      </listitem>
-      <listitem>
-        <para>
-          <ulink url="http://java.sun.com/products/ejb">Sun EJB page</ulink>
-        </para>
-      </listitem>
-      <listitem>
-        <para>
-          <ulink url="http://java.sun.com/javaee/5/docs/api/index.html">Locally mirrored 
-      javax.persistence Javadoc</ulink>
-        </para>
-      </listitem>
-      <listitem>
-        <para>
-          <ulink url="../../api/index.html">OpenJPA API Javadoc</ulink>
-        </para>
-      </listitem>
-      <listitem>
-        <para>
-          <ulink url="../apidocs/index.html">Full OpenJPA Javadoc</ulink>
-        </para>
-      </listitem>
-      <listitem>
-        <para>
-          <ulink url="Persistence.pdf">Locally mirrored JPA
-      specification</ulink>
-        </para>
-      </listitem>
+        <listitem>
+            <para>
+<ulink url="http://java.sun.com/aboutJava/communityprocess/jsr/jsr_220_dataobj.html">
+EJB 3 JSR page</ulink>
+            </para>
+        </listitem>
+        <listitem>
+            <para>
+<ulink url="http://java.sun.com/products/ejb">Sun EJB page</ulink>
+            </para>
+        </listitem>
+        <listitem>
+            <para>
+<ulink url="http://java.sun.com/javaee/5/docs/api/index.html">Locally mirrored
+javax.persistence Javadoc</ulink>
+            </para>
+        </listitem>
+        <listitem>
+            <para>
+<ulink url="../../api/index.html">OpenJPA API Javadoc</ulink>
+            </para>
+        </listitem>
+        <listitem>
+            <para>
+<ulink url="../apidocs/index.html">Full OpenJPA Javadoc</ulink>
+            </para>
+        </listitem>
+        <listitem>
+            <para>
+<ulink url="Persistence.pdf">Locally mirrored JPA specification</ulink>
+            </para>
+        </listitem>
     </itemizedlist>
-  </appendix>
+</appendix>



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