Before JPA 2.1 the concept of Entity Listeners (Injectable EntityListeners) wasn’t defined until JPA 2.1 released. The entity listener concept allows the programmer to designate a methods as a lifecycle callback methods to receive notification of entity lifecycle events. A lifecycle callback methods can be defined on an entity class, a mapped superclass, or an entity …
Java EE
EclipseLink – DDL Schema Generation in JPA 2.1
If you’ve a good experience in the Java Persistence API, you can configure the JPA to generates the required schema. These are not part of the JPA implementation prior to the JPA 2.1 specification. These are considered as the extensions for the JPA provider. However, this has been standardized from the JPA 2.1 release. JPA …
JSTL Function fn:replace()
<fn:replace()> is a string function. The function replace is used to replace the entered string with specified string. The <fn:replace()> function replaces the existing string with another string. Syntax of JSTL Function <fn:replace()> Example of JSTL Function <fn:replace()> Following example demonstrate the working of <fn:replace()> function. In this example we replace the string Welcome to …
JSTL Function fn:trim()
Function <fn: trim ()> is used to remove leading and trailing white spaces, tabs from the start and end of the string. The function returns the string after removing white spaces from both points of the input string. Syntax Of <fn: trim ()> Tag Example Steps for Execution Save the file as trimExample.jsp in eclipse …
JSTL Function fn:toUpperCase()
The <fn: toUpperCase> is function of JSTL which is used to returns all the characters of string to upper case. It converts input string to an upper case string. The string which needs to be changed to upper case is passed as argument and converted string is being returned by the function. Syntax Of <fn: …
JSTL Function fn:toLowerCase()
The <fn: toLowerCase> is function of JSTL which is used to returns all the characters of string to lower case. It converts input string to a lower case string. The string which needs to be changed to lower case is passed as argument and converted string is being returned by the function. Syntax Of <fn: …
JSTL Function fn:length()
The function <fn:length()> is the string function. This function used to find out the length of the entered string. This function displays the number of characters entered in the specified string. Syntax of Function <fn:length()> Example of Function <fn:length()> Steps for Execution Save this file as example.jsp in your eclipse IDE. Now select this jsp …
JPA Entity Primary Key Using @Id and @IdClass
At this tutorial we’ve explained the concept of entity identification. Entity identification is the process in which the Java Persistence Implementation identify an entity uniquely from set of entities that belong to the same type on a memory level or a database level. Each entity that located in the persistence context must has a unique …