Question

java.sql.Connection is implemented into a verbose connection to get more information for unit tests.

Using java 1.6 compiler results in following compilation errors:

The type VerboseConnection must implement the inherited abstract method Connection.createArrayOf(String, Object[]) 
    The type VerboseConnection must implement the inherited abstract method Connection.createBlob() 
    The type VerboseConnection must implement the inherited abstract method Connection.createClob() 
    The type VerboseConnection must implement the inherited abstract method Connection.createNClob() 
    The type VerboseConnection must implement the inherited abstract method Connection.createSQLXML() 
    The type VerboseConnection must implement the inherited abstract method Connection.createStruct(String, Object[]) 
    The type VerboseConnection must implement the inherited abstract method Connection.getClientInfo() 
    The type VerboseConnection must implement the inherited abstract method Connection.getClientInfo(String) 
    The type VerboseConnection must implement the inherited abstract method Connection.isValid(int) 
    The type VerboseConnection must implement the inherited abstract method Connection.setClientInfo(Properties) 
    The type VerboseConnection must implement the inherited abstract method Connection.setClientInfo(String, String) 
    The type VerboseConnection must implement the inherited abstract method Wrapper.isWrapperFor(Class) 
    The type VerboseConnection must implement the inherited abstract method Wrapper.unwrap(Class) 

Implementing the above methods works fine in 1.6 But again if we use
Java 1.5 compiler, results in the following compilation errors

NClob cannot be resolved to a type 
    SQLClientInfoException cannot be resolved to a type 
    SQLClientInfoException cannot be resolved to a type 
    SQLXML cannot be resolved to a type
    The import java.sql.NClob cannot be resolved 
    The import java.sql.SQLClientInfoException cannot be resolved 
    The import java.sql.SQLXML cannot be resolved

Please suggest on how to make it work in both the versions with out
maintaining 2 different files for different versions?

Answer 1

If you need to supply both a Java 1.5 and a Java 1.6 implementation, you could use an abstract base class in your project and add a Java version dependent implementation in a separate project.

Depending on the Java version compile one or the other and include the resulting class files in your main jar file.

This is the approach we use in the implementation of Jaybird (Firebird JDBC driver).