HHH-7667 docs
This commit is contained in:
Strong Liu
parent
57870f32bf
commit
69239e8dd6
|
|
@ -318,13 +318,6 @@
|
|||
created. With <command>create-drop</command>, the database schema is dropped when the
|
||||
<classname>SessionFactory</classname> is closed explicitly.</entry>
|
||||
</row>
|
||||
<row>
|
||||
<entry>cglib.use_reflection_optimizer</entry>
|
||||
<entry><para><literal>true</literal> or <literal>false</literal></para></entry>
|
||||
<entry>If enabled, Hibernate uses CGLIB instead of runtime reflection. This is a system-level
|
||||
property. Reflection is useful for troubleshooting. Hibernate always requires CGLIB even if you disable the
|
||||
optimizer. You cannot set this property in hibernate.cfg.xml.</entry>
|
||||
</row>
|
||||
</tbody>
|
||||
</tgroup>
|
||||
</table>
|
||||
|
|
|
|||
|
|
@ -800,7 +800,7 @@ public class SpaceShip {</programlisting>
|
|||
<section xml:id="sp_query" >
|
||||
<title>Using stored procedures for querying</title>
|
||||
|
||||
<para>Hibernate3 provides support for queries via stored procedures and
|
||||
<para>Hibernate provides support for queries via stored procedures and
|
||||
functions. Most of the following documentation is equivalent for both.
|
||||
The stored procedure/function must return a resultset as the first
|
||||
out-parameter to be able to work with Hibernate. An example of such a
|
||||
|
|
@ -898,7 +898,7 @@ BEGIN
|
|||
<section xml:id="querysql-cud">
|
||||
<title>Custom SQL for create, update and delete</title>
|
||||
|
||||
<para>Hibernate3 can use custom SQL for create, update, and delete
|
||||
<para>Hibernate can use custom SQL for create, update, and delete
|
||||
operations. The SQL can be overridden at the statement level or
|
||||
inidividual column level. This section describes statement overrides. For
|
||||
columns, see <xref linkend="mapping-column-read-and-write" />. <xref
|
||||
|
|
|
|||
|
|
@ -357,7 +357,7 @@ public class Flight implements Serializable {
|
|||
recommended). You can also specify an interface to use for lazy
|
||||
initializing proxies (defaults to the class itself): use
|
||||
<literal>proxyClass</literal> on <classname>@Proxy</classname>.
|
||||
Hibernate will initially return proxies (Javassist or CGLIB) that
|
||||
Hibernate will initially return proxies ( using bytecode provider defined by <literal>hibernate.bytecode.provider</literal>) that
|
||||
implement the named interface. The persistent object will load when a
|
||||
method of the proxy is invoked. See "Initializing collections and
|
||||
proxies" below.</para>
|
||||
|
|
@ -580,7 +580,7 @@ public class Summary {
|
|||
|
||||
<callout arearefs="class17">
|
||||
<para><literal>entity-name</literal> (optional - defaults to the
|
||||
class name): Hibernate3 allows a class to be mapped multiple
|
||||
class name): Hibernate allows a class to be mapped multiple
|
||||
times, potentially to different tables. It also allows entity
|
||||
mappings that are represented by Maps or XML at the Java level. In
|
||||
these cases, you should provide an explicit arbitrary name for the
|
||||
|
|
@ -723,7 +723,7 @@ public class Person {
|
|||
that the class has no identifier property.</para>
|
||||
|
||||
<para>The <literal>unsaved-value</literal> attribute is almost never
|
||||
needed in Hibernate3 and indeed has no corresponding element in
|
||||
needed in Hibernate and indeed has no corresponding element in
|
||||
annotations.</para>
|
||||
|
||||
<para>You can also declare the identifier as a composite identifier.
|
||||
|
|
|
|||
|
|
@ -272,7 +272,7 @@
|
|||
<note>
|
||||
<title>Note</title>
|
||||
<para>
|
||||
In Hibernate3, although the second requirement is not an absolutely hard
|
||||
In Hibernate, although the second requirement is not an absolutely hard
|
||||
requirement of Hibernate, it is recommended.
|
||||
</para>
|
||||
</note>
|
||||
|
|
|
|||
|
|
@ -670,7 +670,7 @@ hibernate.dialect = org.hibernate.dialect.PostgreSQL82Dialect</programlisting>
|
|||
|
||||
<entry>Optimizes second-level cache operation to minimize writes,
|
||||
at the cost of more frequent reads. This setting is most useful
|
||||
for clustered caches and, in Hibernate3, is enabled by default for
|
||||
for clustered caches and, in Hibernate, is enabled by default for
|
||||
clustered cache implementations. <para> <emphasis
|
||||
role="strong">e.g.</emphasis> <literal>true|false</literal>
|
||||
</para></entry>
|
||||
|
|
@ -911,7 +911,7 @@ hibernate.dialect = org.hibernate.dialect.PostgreSQL82Dialect</programlisting>
|
|||
runtime reflection. This is a System-level property and cannot be
|
||||
set in <literal>hibernate.cfg.xml</literal>. Reflection can
|
||||
sometimes be useful when troubleshooting. Hibernate always
|
||||
requires either CGLIB or javassist even if you turn off the
|
||||
requires javassist even if you turn off the
|
||||
optimizer.</para><para> <emphasis role="strong">e.g.</emphasis>
|
||||
<literal>true</literal> | <literal>false</literal> </para></entry>
|
||||
</row>
|
||||
|
|
@ -919,11 +919,8 @@ hibernate.dialect = org.hibernate.dialect.PostgreSQL82Dialect</programlisting>
|
|||
<row>
|
||||
<entry><literal>hibernate.bytecode.provider</literal></entry>
|
||||
|
||||
<entry><para>Both javassist or cglib can be used as byte
|
||||
manipulation engines; the default is
|
||||
<literal>javassist</literal>.</para><para> <emphasis
|
||||
role="strong">e.g.</emphasis> <literal>javassist</literal> |
|
||||
<literal>cglib</literal> </para></entry>
|
||||
<entry><para>At the moment, <literal>javassist</literal> is the only supported bytecode provider.</para><para> <emphasis
|
||||
role="strong">e.g.</emphasis> <literal>javassist</literal></para></entry>
|
||||
</row>
|
||||
</tbody>
|
||||
</tgroup>
|
||||
|
|
|
|||
|
|
@ -256,7 +256,7 @@ session.flush();]]></programlisting>
|
|||
database. We will also assume that both <literal>Parent</literal> and <literal>Child</literal> have generated
|
||||
identifier properties of type <literal>Long</literal>. Hibernate will use the identifier and
|
||||
version/timestamp property value to determine which of the children are new. (See
|
||||
<xref linkend="objectstate-saveorupdate"/>.) <emphasis>In Hibernate3, it is no longer necessary to specify
|
||||
<xref linkend="objectstate-saveorupdate"/>.) <emphasis>In Hibernate, it is no longer necessary to specify
|
||||
an <literal>unsaved-value</literal> explicitly.</emphasis>
|
||||
</para>
|
||||
|
||||
|
|
|
|||
|
|
@ -3,7 +3,7 @@
|
|||
<chapter xml:id="filters" xmlns="http://docbook.org/ns/docbook" >
|
||||
<title>Filtering data</title>
|
||||
|
||||
<para>Hibernate3 provides an innovative new approach to handling data with
|
||||
<para>Hibernate provides an innovative new approach to handling data with
|
||||
"visibility" rules. A <emphasis>Hibernate filter</emphasis> is a global,
|
||||
named, parameterized filter that can be enabled or disabled for a particular
|
||||
Hibernate session.</para>
|
||||
|
|
@ -11,7 +11,7 @@
|
|||
<section xml:id="objectstate-filters" revision="1">
|
||||
<title>Hibernate filters</title>
|
||||
|
||||
<para>Hibernate3 has the ability to pre-define filter criteria and attach
|
||||
<para>Hibernate has the ability to pre-define filter criteria and attach
|
||||
those filters at both a class level and a collection level. A filter
|
||||
criteria allows you to define a restriction clause similar to the existing
|
||||
"where" attribute available on the class and various collection elements.
|
||||
|
|
|
|||
|
|
@ -61,7 +61,7 @@
|
|||
<literal>hibernate-mapping</literal>. This allows you to extend a class hierarchy by adding
|
||||
a new mapping file. You must specify an <literal>extends</literal> attribute in the subclass mapping,
|
||||
naming a previously mapped superclass. Previously this feature made the ordering of the mapping
|
||||
documents important. Since Hibernate3, the ordering of mapping files is irrelevant when using the
|
||||
documents important. Since Hibernate, the ordering of mapping files is irrelevant when using the
|
||||
extends keyword. The ordering inside a single mapping file still needs to be defined as superclasses
|
||||
before subclasses.
|
||||
</para>
|
||||
|
|
|
|||
|
|
@ -12,7 +12,7 @@
|
|||
over-ridden by a particular HQL or <literal>Criteria</literal>
|
||||
query.</para>
|
||||
|
||||
<para>Hibernate3 defines the following fetching strategies:</para>
|
||||
<para>Hibernate defines the following fetching strategies:</para>
|
||||
|
||||
<itemizedlist>
|
||||
<listitem>
|
||||
|
|
@ -104,7 +104,7 @@
|
|||
<section xml:id="performance-fetching-lazy">
|
||||
<title>Working with lazy associations</title>
|
||||
|
||||
<para>By default, Hibernate3 uses lazy select fetching for collections
|
||||
<para>By default, Hibernate uses lazy select fetching for collections
|
||||
and lazy proxy fetching for single-valued associations. These defaults
|
||||
make sense for most associations in the majority of applications.</para>
|
||||
|
||||
|
|
@ -144,7 +144,7 @@ Integer accessLevel = (Integer) permissions.get("accounts"); // Error!</program
|
|||
|
||||
<para>On the other hand, you can use join fetching, which is non-lazy by
|
||||
nature, instead of select fetching in a particular transaction. We will
|
||||
now explain how to customize the fetching strategy. In Hibernate3, the
|
||||
now explain how to customize the fetching strategy. In Hibernate, the
|
||||
mechanisms for choosing a fetch strategy are identical for single-valued
|
||||
associations and collections.</para>
|
||||
</section>
|
||||
|
|
@ -224,9 +224,9 @@ Integer accessLevel = (Integer) permissions.get("accounts"); // Error!</program
|
|||
is needed for lazy behavior in single-ended associations. The target
|
||||
entity of the association must be proxied. Hibernate implements lazy
|
||||
initializing proxies for persistent objects using runtime bytecode
|
||||
enhancement which is accessed via the CGLIB library.</para>
|
||||
enhancement which is accessed via the bytecode provider.</para>
|
||||
|
||||
<para>At startup, Hibernate3 generates proxies by default for all
|
||||
<para>At startup, Hibernate generates proxies by default for all
|
||||
persistent classes and uses them to enable lazy fetching of
|
||||
<literal>many-to-one</literal> and <literal>one-to-one</literal>
|
||||
associations.</para>
|
||||
|
|
@ -273,7 +273,7 @@ System.out.println(cat==dc); // false</programlisting
|
|||
<programlisting role="JAVA">cat.setWeight(11.0); // hit the db to initialize the proxy
|
||||
System.out.println( dc.getWeight() ); // 11.0</programlisting>
|
||||
|
||||
<para>Third, you cannot use a CGLIB proxy for a <literal>final</literal>
|
||||
<para>Third, you cannot use a bytecode provider generated proxy for a <literal>final</literal>
|
||||
class or a class with any <literal>final</literal> methods.</para>
|
||||
|
||||
<para>Finally, if your persistent object acquires any resources upon
|
||||
|
|
@ -670,7 +670,7 @@ Customer customer = (Customer) session.get( Customer.class, customerId );
|
|||
<section xml:id="performance-fetching-lazyproperties">
|
||||
<title>Using lazy property fetching</title>
|
||||
|
||||
<para>Hibernate3 supports the lazy fetching of individual properties.
|
||||
<para>Hibernate supports the lazy fetching of individual properties.
|
||||
This optimization technique is also known as <emphasis>fetch
|
||||
groups</emphasis>. Please note that this is mostly a marketing feature;
|
||||
optimizing row reads is much more important than optimization of column
|
||||
|
|
@ -1423,7 +1423,52 @@ hibernate.cache.use_structured_entries true</programlisting>
|
|||
<literal>org.hibernate.SessionFactory.evictQueries()</literal>.</para>
|
||||
</section>
|
||||
</section>
|
||||
<section xml:id="bytecode-enhancement" revision="1">
|
||||
<title>Bytecode Enhancement</title>
|
||||
<para>Hibernate internally needs an entry ( <classname>org.hibernate.engine.spi.EntityEntry</classname> ) to tell
|
||||
the current state of an object with respect to its persistent state, when the object is associated with a
|
||||
<classname>Session</classname>. However, maintaining this association was kind of heavy operation due to lots of
|
||||
other rules must by applied, since 4.2.0, there is a new improvement designed for this purpose, which will reduce
|
||||
session-related memory and CPU overloads.
|
||||
</para>
|
||||
<para>Basically, the idea is, instead of having a customized ( kind of heavy and which was usually identified as hotspot )
|
||||
map to do the look up, we change it to </para>
|
||||
<programlisting role="JAVA"><![CDATA[EntityEntry entry = (ManagedEntity)entity.$$_hibernate_getEntityEntry();
|
||||
]]></programlisting>
|
||||
|
||||
<para>There are three ways to get benefits from this new improvement:</para>
|
||||
|
||||
<section xml:id="entityentry-lookup-impl-interface">
|
||||
<title>Implementing <classname>org.hibernate.engine.spi.ManagedEntity</classname> interface</title>
|
||||
<para>An entity can choose to implement this interface by itself, then it is the entity's responsibility to maintain
|
||||
the bi-association that essentially provides access to information about an instance's association to a
|
||||
Session/EntityManager.
|
||||
More info about <classname>org.hibernate.engine.spi.ManagedEntity</classname> please find from its javadoc.
|
||||
</para>
|
||||
</section>
|
||||
|
||||
<section xml:id="entityentry-lookup-impl-interface-by-wrapper">
|
||||
<title>Runtime instrument</title>
|
||||
<para>Sometimes, you probably don't want to implement an intrusive interface, maybe due to portable concern,
|
||||
which is fine and Hibernate will take care of this internally with a wrapper class which implements that interface,
|
||||
and also an internal cache that maps this entity instance and the wrapper together.</para>
|
||||
|
||||
<para>Obviously, this is the easiest way to choose, since it doesn't require any change of the project source code,
|
||||
but it also cost more memory and CUP usage, comparing to the first one.</para>
|
||||
</section>
|
||||
|
||||
<section xml:id="entityentry-lookup-buildtime-instrument">
|
||||
<title>Buildtime instrument</title>
|
||||
<para>Besides above two approaches, Hibernate also provides you the third choice, which is an ANT task (
|
||||
<classname>org.hibernate.tool.enhance.EnhancementTask</classname>) that can be used at build time to
|
||||
instrument your entity classes with the required interfaces and methods.
|
||||
|
||||
Meanwhile, the maven and gradle plugin are still under development and will be available soon.
|
||||
</para>
|
||||
|
||||
</section>
|
||||
|
||||
</section>
|
||||
<section xml:id="performance-collections">
|
||||
<title>Understanding Collection performance</title>
|
||||
|
||||
|
|
|
|||
|
|
@ -768,7 +768,7 @@ where p.name = some elements(list.names)]]></programlisting>
|
|||
Note that these constructs - <literal>size</literal>, <literal>elements</literal>,
|
||||
<literal>indices</literal>, <literal>minindex</literal>, <literal>maxindex</literal>,
|
||||
<literal>minelement</literal>, <literal>maxelement</literal> - can only be used in
|
||||
the where clause in Hibernate3.
|
||||
the where clause in Hibernate.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
|
|
|
|||
|
|
@ -9,7 +9,7 @@
|
|||
also provides a clean migration path from a direct SQL/JDBC based
|
||||
application to Hibernate.</para>
|
||||
|
||||
<para>Hibernate3 allows you to specify handwritten SQL, including stored
|
||||
<para>Hibernate allows you to specify handwritten SQL, including stored
|
||||
procedures, for all create, update, delete, and load operations.</para>
|
||||
|
||||
<section xml:id="querysql-creating" revision="4">
|
||||
|
|
@ -800,7 +800,7 @@ public class SpaceShip {</programlisting>
|
|||
<section xml:id="sp_query" revision="1">
|
||||
<title>Using stored procedures for querying</title>
|
||||
|
||||
<para>Hibernate3 provides support for queries via stored procedures and
|
||||
<para>Hibernate provides support for queries via stored procedures and
|
||||
functions. Most of the following documentation is equivalent for both.
|
||||
The stored procedure/function must return a resultset as the first
|
||||
out-parameter to be able to work with Hibernate. An example of such a
|
||||
|
|
@ -898,7 +898,7 @@ BEGIN
|
|||
<section xml:id="querysql-cud">
|
||||
<title>Custom SQL for create, update and delete</title>
|
||||
|
||||
<para>Hibernate3 can use custom SQL for create, update, and delete
|
||||
<para>Hibernate can use custom SQL for create, update, and delete
|
||||
operations. The SQL can be overridden at the statement level or
|
||||
inidividual column level. This section describes statement overrides. For
|
||||
columns, see <xref linkend="mapping-column-read-and-write" />. <xref
|
||||
|
|
|
|||
|
|
@ -100,7 +100,6 @@
|
|||
<artifactId>slf4j-simple</artifactId>
|
||||
</dependency>
|
||||
|
||||
<!-- Hibernate gives you a choice of bytecode providers between cglib and javassist -->
|
||||
<dependency>
|
||||
<groupId>javassist</groupId>
|
||||
<artifactId>javassist</artifactId>
|
||||
|
|
|
|||
Loading…
Reference in New Issue