@Override
  public Object unwrap(Class iface) throws SQLException {
    return iface;
  }
Place holder for abstract method java.lang Object unwrap(java.lang.Class) in java.sql.Wrapper
required by jdk 1.6

@param iface - a Class defining an interface.
@return java.lang.Object
geode-core/src/main/java/org/apache/geode/internal/datasource/GemFireBasicDataSource.java