java - How to correctly override BasicDataSource for Spring and Hibernate -

currently have following basic data source in spring:

<bean id="dbcpdatasource" class="org.apache.commons.dbcp.basicdatasource" destroy-method="close">     <property name="driverclassname" value="com.mysql.jdbc.driver" />     <property name="url" value="jdbc:mysql://localhost/test?relaxautocommit=true" />     ... </bean> 

now need provide custom data source based on server environment (not config), need calculate driverclassname , url fields based on condition.

i tried overriding createdatasource() method:

public class mydatasource extends basicdatasource {      @override     protected synchronized datasource createdatasource() throws sqlexception {         if(condition) {             super.setdriverclassname("com.mysql.jdbc.driver");             super.seturl("jdbc:mysql://localhost/test?relaxautocommit=true");         } else {             //...         }         return super.createdatasource();     } } 

which works, noticed createdatasource() getting called each time query executed(?), rather move condition testing elsewhere.

i tried overriding setdriverclassname() , seturl() works , getting called once can tell, need provide values in spring configuration in order trigger setters not called otherwise:

<bean id="dbcpdatasource" class="org.apache.commons.dbcp.basicdatasource" destroy-method="close">     <property name="driverclassname" value="whatever" />     <property name="url" value="whatever" />     ... </bean> 

which might confusing.

are there better solutions?

there no need extend basicdatasource. inheritance strongest form of coupling , should avoided unless have real reason use it.

you have 2 options:

• create wrapper (use composition instead of inheritance)

  public class mydatasource implements datasource {     private basicdatasource target = new basicdatasource();     public mydatasource() {         if (condition) {             target.setdriverclassname("com.mysql.jdbc.driver");                             target.seturl("jdbc:mysql://localhost/test?relaxautocommit=true");          } else { ... }     }     public connection getconnection() {         return target.getconnection();     }     ... etc ... } 

• create factory (since need customize creation phase of object, don't need control whole lifetime of it).

   public class mydatasourcefactory {     public datasource createdatasource() {         basicdatasource target = new basicdatasource();         if (condition) {             target.setdriverclassname("com.mysql.jdbc.driver");                             target.seturl("jdbc:mysql://localhost/test?relaxautocommit=true");          } else { ... }         return target;     } } 

  .

  <bean id = "factory" class = "mydatasourcefactory" /> <bean id = "dbcpdatasource"       factory-bean = "factory" factory-method = "createdatasource">      <property ... /> </bean> 

edit: note still can configure object obtained factory regular spring bean.

also if condition simple enough, can avoid writing own code @ using declarative approaches provided spring, such spring expression language.