A question about compatiblilty of JDBC

Question

Hi, there,
I have a question about JDBC 3.0 in JDK1.4.1.
We build a .jar using JDK1.4.1 and this .jar file
provides JDBC 3.0 interface.
I then tried to call the interface under JDK1.3.1
but it keeps asking me about the getParameterMetaData()
in PreparedStatement.
(The error message like this:
Exception in thread "main" java.lang.NoClassDefFoundError: java/sql/ParameterMetaData dbmaker.sql.JdbcOdbcConnection.prepareStatement(JdbcOdbcConnection.java:257)
I did implement the getParameterMetaData() method,
but I didn't call this method in my testing program.
It's quite strange since when JDK1.2 was release,
we implemented the getBlob() method in
ResultSet class and there's no problem when we
use JDK1.1 run time to call this ResultSet object.
Could any one tell me why? Is this caused by a
compatibility problem between JDK1.4 and the
older versions of JDK?

Answer 1

Hi, there,
Let me outline the condition by examples so that maybe you can help me. PLEASE! Could somebody tell us what's wrong?
- CASE 1:
In JDK1.2, we implemented a new method getBlob which returns the type of Blob (this is done according to JDBC 2.0 specification.) in ResultSet class. We can use the .jar compiled by jdk1.2 in jdk1.1 environment.
e.g. We make a xyz.jar by jdk1.2 and the xyz.jar includes new method getBlob in ReaultSet class. Then, one java application including ResultSet class CAN run under jdk1.1 with xyz.jar, if the method ResultSet.getBlob() is not called.
- CASE 2:
BUT, the following case which is the same as in the above condition will fail in jdk1.3 environment.
In JDK 1.4, we implemented a new method getParameterMetaData() which returns the type of ParameterMetaData. (BTW, this is done according to JDBC 3.0 specification.) in PreparedStatement class. We CANNOT use the .jar compiled by jdk1.4 in jdk1.3 environment.
e.g. We make a ttt.jar by jdk1.4 and ttt.jar includes the new method getParameterMetaData() in PreparedStatement class. Then, one java application including PreparedStatement class CANNOT be run under jdk1.3 with ttt.jar, even when the method PreparedStatement.getParameterMetaData() is not called.