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DATADOC-82 - Document QueryDslPredicateExecutor

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Mark Pollack
2011-04-07 01:41:37 -04:00
parent b00684d968
commit 302f111c56
1 changed files with 24 additions and 10 deletions
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src/docbkx/reference/mongo-repositories.xml
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@@ -304,9 +304,9 @@ public class PersonRepositoryTests {
<para>Mongo repository support integrates with the <ulink
url="http://www.querydsl.com/">QueryDSL</ulink> project which provides a
meant to perform type-safe queries (no strings) in Java. To quote from
the project description, "Instead of writing queries as inline strings
or externalizing them into XML files they are constructed via a fluent
means to perform type-safe queries in Java. To quote from the project
description, "Instead of writing queries as inline strings or
externalizing them into XML files they are constructed via a fluent
API." It provides the following features</para>
<itemizedlist>
@@ -334,22 +334,32 @@ public class PersonRepositoryTests {
</listitem>
</itemizedlist>
<para>This will enable you to write queries as shown below</para>
<para>Please refer to the QueryDSL documentation which describes how to
bootstrap your environment for APT based code generation <ulink
url="http://source.mysema.com/static/querydsl/2.1.2/reference/html/ch02.html#d0e112">using
Maven</ulink> or <ulink
url="http://source.mysema.com/static/querydsl/2.1.2/reference/html/ch02.html#d0e131">using
Ant</ulink>.</para>
<para>Using QueryDSL you will be able to write queries as shown
below</para>
<programlisting>QPerson person = new QPerson("person");
List&lt;Person&gt; result = repository.findAll(person.address.zipCode.eq("C0123"));
Page&lt;Person&gt; page = repository.findAll(person.lastname.contains("a"),
new PageRequest(0, 2, Direction.ASC, "lastname"));</programlisting>
<para>QPerson is a class that is generated (via the Java annotation post
processing tool) which is a Predicate that allows you to write type safe
<para><classname>QPerson</classname> is a class that is generated (via
the Java annotation post processing tool) which is a
<classname>Predicate</classname> that allows you to write type safe
queries. Notice that there are no strings in the query other than the
value "C0123".</para>
<para>The use of the generated Predicate class is made available via the
interface QueryDslPredicateExecutor which is shown below</para>
<para>You can use the generated <classname>Predicate</classname> class
via the interface
<interfacename>QueryDslPredicateExecutor</interfacename> which is shown
below</para>
<programlisting>public interface QueryDslPredicateExecutor&lt;T&gt; {
@@ -366,13 +376,17 @@ Page&lt;Person&gt; page = repository.findAll(person.lastname.contains("a"),
</programlisting>
<para>To use this in your repository implementation, simply inherit from
it as well. This is shown below</para>
it in additiion to other repository interfaces. This is shown
below</para>
<programlisting>public interface PersonRepository extends MongoRepository&lt;Person, String&gt;, QueryDslPredicateExecutor&lt;Person&gt; {
// additional finder methods go here
}</programlisting>
<para>We think you will find this an extremely powerful tool for writing
MongoDB queries.</para>
</section>
</section>
</chapter>