Struts Tutorials:
Struts2 Tag CheckBoxList
, Checkbox, Iterator, IF
Struts2 Tag Library Example
Struts2 Tiles Example
Struts2 Tiles I18N Example
Struts2 Questions
Struts Tiles I18N Example
Struts Eclipse MVC
Struts2 Tags
Struts2 Example and Tutorial
Struts MVC
Struts2 Validation
Hibernate Tutorials:
Hibernate Case Study
Class Hierarchy Persist Example
Using Hibernate Interceptor
Hibernate Questions with Answer
Hibernate Many-to-Many Mapping Example
Hibernate one-to-many Mapping Example
Hibernate and ORM tools
Spring Hibernate Example
Hibernate SessionFactory Example
Hibernate Mapping Class Hierarchy
Hibernate Questions
Hibernate SessionFactory Questions
Spring Hibernate Example:
Spring Hibernate Case Study
Written By : Amit
Title :
ways create Hibernate SessionFactory
Description :
Example
More...
|
Written By : Amit
Title :
Spring Hibernate Integration example
Description :
Example
More...
|
Written By : Amit
Title :
ORM Hibernate Best FIT
Description :
Discussion
More...
|
Written By : Amit
Title :
One to Many mapping example
Description :
Code
More...
|
Written By : Amit
Title :
Many to Many Mapping Example
Description :
code
More...
|
Written By : Amit
Title :
Interview questions answer
Description :
discussion
More...
|
Written By : Amit
Title :
Interceptor use log SQL statements
Description :
example code
More...
|
Written By : Amit
Title :
Class Hierarchy Persist example
Description :
code
More...
|
| Hibernate Tutorial,Interceptor-use-log-SQL-statements,example-code
Author : Amit
Date (Year/Month/Date): 2009-02-18
Using Hibernate interceptors to log SQL statements | |
Interceptors can be used in cases where we may require
some sort of callback methods called just before the
actual operation is called. For example If it is required
to log any perticular SQL in some different log/audit file,
then we can set a simple Interceptor like CaptureSQL or
LogSQL, just while opening Sesson using SessionFactory
openSession (Interceptor) method.
Following sample interceptor does the logging of SQL
on prepare statement.
import org.apache.log4j.Logger;
import org.hibernate.EmptyInterceptor;
public class CaptureSQL extends EmptyInterceptor {
private static Logger log = Logger.getLogger("L1");
public String onPrepareStatement(String sql) {
log.debug("Loging SQL statement ...... start");
log.debug(sql);
log.debug("Loging SQL statement ...... end");
return sql;
}
}
|
CaptureSQL is the user defined class that extends
org.hibernate.EmptyInterceptor to become receiving
callback overridden method, such as
"onPrepareStatement", when ever a Session is opened,
by calling SessionFactory.openSession(new CaptureSQL()).
Appropriate log4j.properties file should be configured
to be able to handle these logging part. My sample log4j.properties
file is as follows:
log4j.rootLogger=DEBUG
log4j.logger.L1=INHERIT, L
log4j.appender.L=org.apache.log4j.FileAppender
log4j.appender.L.file=sample.txt
log4j.appender.L.layout=org.apache.log4j.PatternLayout
log4j.appender.L.layout.ConversionPattern=%d [%t] %C{1} - %m%n
|
And the Client code is as follows:
log4j.rootLogger=DEBUG
log4j.logger.L1=INHERIT, L
log4j.appender.L=org.apache.log4j.FileAppender
log4j.appender.L.file=sample.txt
log4j.appender.L.layout=org.apache.log4j.PatternLayout
log4j.appender.L.layout.ConversionPattern=%d [%t] %C{1} - %m%n
|
On executing Client code we can see logs are getting written
onto the sample.txt log file, as shown follows:
2009-01-04 09:01:11,578 [main] CaptureSQL - Loging SQL statement .start
2009-01-04 09:01:11,593 [main] CaptureSQL -
<<Your SQL used for the operation on the Session opened with
CatureSQL as interceptor>>
2009-01-04 09:01:11,593 [main] CaptureSQL - Loging SQL statement .end
There are many other interesting callback methods
can be used from EmptyInterceptor, such as
findDirty -> to check where the Entity in use is dirty or not.
-> if this method returns an empty int[] array, then
the Entity object supplied in argument of this
method is not dirty.
-> if this method returns an empty int[] array, then
the Entity object is dirty or is updated by some other
process in database.
-> by returning a null from the overridden findDirty method
one can opt for using Hibernate's own or default dirty
checking mechanism.
onLoad -> it is called just before Entity object is initialized.
onDelete -> it is called just before Entity object is deleted.
and many more callback methods as defined in
org.hibernate.Intercept interface.
Hibernate Question on Interceptor 2:
Can there be any Interceptor for SessionFactory, so that
it can be used across all the Session from this SessionFactory?
Yes, there can be an Interceptor defined in org.hibernate.cfg.Configuration
to be defined during SessionFactory creation.
Configuration.setInterceptor method can be used for this purpose.
Hibernate Question on Interceptor 3:
Can one be able to use Hibernate Session from within the callback
methods of Interceptor?
No, Session may not be used from the callback methods of Interceptor.
Hibernate Question on Interceptor 4:
Can the collection be recreated/initialized lazily while executing any
callback method from Interceptor?
No, Collection may not be lazily initialized, from callback method
of Interceptors.
 | Author of this article/writeup has expressed his/her willingness |
to help or guide users with any technical difficulties he/she faces
while working with the example code environment setting up, running
and resolving any such exception raised during compile or at runtime.
You may ask for any technical doubt or seek technical help related to
this article by using following form to reach for technical help
from the Author for FREE.
This article's Author shall be reading your request and responding
within reasonable time (no resolution timeframe defined as such).
|
|
<- requires login
