Hi all,
must apologise for being so quiet,busy with my 'real' job etc. However
this doesn't mean I've been ignoring what I want to do.
I've been reading around the code to determine the files that I am going
to require to initiate this little modification. I think I am begining
to understand how things work a little better. Firstly however I want to
ensure I have well understood.
The file sqlgrammar.jj is read by javacc and creates a bunch of other
.java clases.
SQLParserConstants.java is one of these files, it is an interface that
is implemented by the SQLParser class (also created from sqlgrammar.jj).
So if I can modify sqlgrammar.jj I could 'inject' into the SQLParser
class a method that return the list of static final members (stored in
the tokenImage string array member, so in fact I could just return this
member).
My problems currently now revolve around the following.
DAG has created a method that reads the sqlgrammar.jj file directly and
creates the Keywords.java file. I can't seem to find this in my source
tree, is this related to needing the specific DERBY-3256 checkout. I've
tried using the SVN plugin for eclipse to find this checkout, but so far
to no success. Any chance someone could walk me through doing this from
the CLI (ubuntu 12.04).
Should I mention at this point I'm rather new to SVN (actually version
control in general!), did I say previously this is my first multi person
project?
sorry I digress....
I've located the files that I think I'm going to need.
EmbededDataBaseMetaData[40].java and TestDBMetaData.java where I will
put my < getDerbyKeyWords() > method and test.
Rik thanks for waving your hands about the compile time tool. I think
this may be what I need to implement my < getTokenImage() > so any
pointers would be great.
Once I've got the method working locally I guess I'll need to create a
bug or something, that points to the various JIRA issues, and then solve
it.... but for me that comes a little later. For now I want to write the
method into my local tree only. Then recompile, test ... blah blah blah...
Is this an acceptable way in which to proceed? Any suggestions advice
are welcome.
Thanks in advance.
David.
On 10/09/12 01:23, Dag Wanvik wrote:
Hi,
I added an experimental patch to DERBY-3256 which seems to do (part
of) the job. It uses the actual lists from sqlgrammar.jj to generate
Keywords.java at compile time, and wraps those in a table function.
There is no metadata function in it but it could be used to provide
those functions, I think, if we decide that's the way to go.
Dag
On 05.09.2012 23:28, david myers wrote:
On 05/09/12 06:25, Katherine Marsden wrote:
On 9/4/2012 7:44 PM, Bryan Pendleton wrote:
I've had success in pointing Eclipse to the source code that I
have built. I have had a nice look around for the file that I am
interested in, which from the previously mentioned JIRA issues etc
suggest a file called sqlgrammar.jj
only problem is I can't find it!
It's possible that Eclipse doesn't grok '.jj' files in its normal
configuration.
The file should be in your source tree as:
./java/engine/org/apache/derby/impl/sql/compile/sqlgrammar.jj
There is a compiler-generation tool that processes this file during
the Ant build of Derby and generates Java source from the grammar.
The tool that generates the java code for the parser from
sqlgrammar.jj is Javacc. The generated code is in
generated/java/org/apache/derby/impl/sql/compile which is fun to
look at but shouldn't be changed.
I think there may be an exclipse plugin for javacc but I have never
used one.
Kathey
Hello again all,
Sorry I hate to pollute the thread, but I want to ensure that I do
things 'the apache way' and not just my way!
So I need a little advice.
First some info.
The file as mentioned by Bryan has been located. Thanks to Kathey's
pointer I have found the actual java file that is going to be of
interest to me.
The files that I think are going to be informative are:
SQLParserConstants.java ~ this is the interface
SQLParser ~ a class file that implements this interface is
This file is found in Source Folder: generated/java/
package:
org.apache.derby.impl.sql.compile
So now it is a question of testing out my idea !
The interface <SQLParserConstants.java> has no methods, only static
final "int" members.
This leads me to a potential solution as follows:
Create a method that has an inner class that implements the
SQLParserConstants.java interface
This inner class has a single method that grabs all of the members
and inserts them into a arrayList<String> - for "equal time access"
to the values.
We can then access this arrayList and compare a passed in value to
determine if the value exists in the list.
My first idea is to test the method within a test class, a good
candidate for its location is the following I think.
TestDbMetaData
located in source folder java/test
package ~ org.apache.derbyTesting.functionTests.tests.jdbc4
Or alternatively I can create a separate test class to test the idea
(which would probably be my preference to start with, then once it
works as I would like it to everything can be copied into a more
sensible location.
Once I have the method functioning I could add it into a specific
package (probably databaseMetaData), then test it in situ.
Does the above seem like a valid process?
I have a few queries about the test suite.
I have been using Junit4 from within eclipse, and I'm aware that you
use Junit 3.8. I notice that with your test files you don't use
annotations for the methods. With the exception of the setup and tear
down methods, how do you control the flow through the test? In Junit
4 you place a <@Test> token on the line before the method if you want
the method to run, along with annotations like <@before> if there are
any that need to come before other stuff.
Also my test classes have only really had 1 method I want to run at a
time, so I just comment out the <@Test> annotation to effectively
turn off the method.
Please add your comments.
David
