When exporting a DataSource as a service using spring-osgi the DataSource will get proxied. This will cause subsequent lookups for the active transaction to fail when the lookups occur using the different proxies of the DataSource.

The reason I'm reporting it here as a bug is that the DataSource interface does not define hashCode or equals, which actually means that the behavior of using a DataSource as a key in a Map is undefined.

I don't really see a good solution to this problem unfortunately, as the DataSource interface simply defines no way to determine if it's the same as another instance.

However, there is a workaround, namely to extend the DataSource interface to expose equals and hashCode and to define a EHDataSourceAdapter which implements these using the identity hash code of the adapter instance. Instead of using the raw data source in the application one would then use the wrapped data source (typically defined in the spring application context), giving a well-defined eqhash behavior and allowing it to be used as a map key.

With OSGI becoming more popular maybe something like this could be included somewhere as data source util classes, or maybe you guys can come up with a better solution. :-)

Issues linked to this one are:
http://static.springframework.org/spring-osgi/docs/1.0/reference/html/known-issues.html#OSGI-245
http://jira.springframework.org/browse/OSGI-245

The EHDataSource is just DataSource extended but equals and hashCode added. In EhDataSourceAdapter the important methods are equals and hashCode, the others just delegating to the real data source. The only problem with the EHDataSourceAdapter is that it implements JDK1.6 data source, so maybe it should be dynamic as Sun made incompatible changes to the interface. :-(( And perhaps a noarg constructor and setter should be included for people that do not like constructor injection.

public interface EHDataSource extends DataSource {

boolean equals(Object obj);

int hashCode();

}

public class EHDataSourceAdapter implements EHDataSource {

private final DataSource dataSource;

public EHBasicDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}

@Override
public boolean equals(Object obj) {
if (!(obj instanceof EHDataSource)){
return false;
}
EHDataSource other = (EHDataSource) obj;
return other.hashCode() == hashCode();

}

@Override
public int hashCode() {
return System.identityHashCode(this);
}

public Connection getConnection() throws SQLException {
return dataSource.getConnection();
}

public Connection getConnection(String username, String password)
throws SQLException {
return dataSource.getConnection(username, password);
}

public int getLoginTimeout() throws SQLException {
return dataSource.getLoginTimeout();
}

public PrintWriter getLogWriter() throws SQLException {
return dataSource.getLogWriter();
}

public boolean isWrapperFor(Class<?> iface) throws SQLException {
return dataSource.isWrapperFor(iface);
}

public void setLoginTimeout(int seconds) throws SQLException {
dataSource.setLoginTimeout(seconds);
}

public void setLogWriter(PrintWriter out) throws SQLException {
dataSource.setLogWriter(out);
}

public <T> T unwrap(Class<T> iface) throws SQLException {
return dataSource.unwrap(iface);
}

}