✅ JDBC native

Sometimes a developer needs to work with the Connection directly, create statements, execute them, and process the results in a way that the annotations do not cover.
The annotation processor therefore provides a mechanism to call a hand-written method.

• Bridges to a user-provided static method; by default the processor searches within the same interface, while cls and method override the target.
• The target method must be static and accept a java.sql.Connection as its first parameter, followed by the interface parameters in the same order and type.
  • The first parameter must be java.sql.Connection.
  • The remaining parameters must match the interface method in count and type.
  • The return type must be assignable to the interface method’s return type.
  • Nullness semantics must stay compatible between source and target signatures.
• Exception handling:
  • Any SQLException is wrapped in JdbcException.
  • All other exceptions must either be runtime exceptions or be type-compatible with the interface method signature.

Note

• Do not close the connection yourself, close all other resources you have created with in this method.
• Do not change the transaction isolation level or commit inside your handwritten method.

Example

Simple example

@JdbcNative
List<String> getTables(String tableNamePattern);

static List<String> getTables(Connection con, String tableNamePattern) throws SQLException {
    DatabaseMetaData md = con.getMetaData();
    try (var rs0 = md.getTables(null, "PUBLIC", tableNamePattern, new String[]{"TABLE"})) {
        return ResultSetUtils.toList(rs0, (rs) -> {
            return rs.getString("TABLE_TYPE") + ", " +
                    rs.getString("TABLE_CAT") + ", " +
                    rs.getString("TABLE_SCHEM") + ", " +
                    rs.getString("TABLE_NAME");
        });
    }
}