Hi fellow developers,
How can I over-ride the JDBCTestElementBeanInfoSupport constructor
successfully, without having to ditch inheritance from
AbstractJDBCTestElement?
I'm creating a new JDBC test element in JMeter 2.6 but I've hit issues
with the GUI. Although I've created test elements before, I've added GUI
properties rather than modified them.
If I extend JDBCTestElementBeanInfoSupport everything is fine, but I
have the full range of query types in the GUI. My requirement is to
restrict query type to SELECT or PREPARED_SELECT. Thus I am attempting
to over-ride the constructor for the parent class
JDBCTestElementBeanInfoSupport.java, ie.
public MyJDBCTestElement(Class<?> beanClass) {
super(beanClass);
// Override default query types
PropertyDescriptor p = property("queryType"); // $NON-NLS-1$
p.setValue(NOT_UNDEFINED, Boolean.TRUE);
p.setValue(DEFAULT, AbstractJDBCTestElement.SELECT);
p.setValue(NOT_OTHER,Boolean.TRUE);
p.setValue(TAGS,new String[]{
AbstractJDBCTestElement.SELECT,
AbstractJDBCTestElement.PREPARED_SELECT
});
}
This results in the compiler errors:
[javac] SELECT is not public in
org.apache.jmeter.protocol.jdbc.AbstractJDBCTestElement; cannot be
accessed from outside package
[javac] PREPARED_SELECT is not public in
org.apache.jmeter.protocol.jdbc.AbstractJDBCTestElement; cannot be
accessed from outside package
The obvious thing to do is simply to redefine these constants locally,
but as stated inAbstractJDBCTestElement.java, "These must not be
changed, as they are used in the JMX files", so, equally, they should
not really be redefined either.
Is there a specific reason why these constants are not declared as
public and documented on
http://jmeter.apache.org/api/constant-values.html? Maybe the answer
lies in my next observations....
My constructor over-ride doesn't work - it seems to have no effect. I
tried to strip it back by extending BeanInfoSupport instead of
JDBCTestElementBeanInfoSupport, and adding only GUI elements that I
wanted, but all the original GUI components appear at run-time, exactly
as before. Even when I comment out all the JDBC GUI elements in my test
element, they still appear at run time.
I've established that this is because my new test element extends
AbstractJDBCTestElement - the JDBC GUI elements disappear only when I
extend AbstractTestElement - ie. the GUI behaviour is due to the test
element's inherited type, not its GUI component.
So, it appears that simply extending AbstractJDBCTestElement, which is
the obvious thing to do when creating a new JDBC test element,
automatically implies a relationship to JDBCTestElementBeanInfoSupport,
complete with the pre-determined list of "queryType" TAGS created via
its constructor. I've verified this by commenting out one of the TAG
strings and observing that it disappears in all JDBC test elements,
including mine! Hence, my question at the top of the message....
Thanks, Roderick
