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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

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package javax.sql;

import java.sql.*;

/**

 * The facility that a disconnected {@code RowSet} object calls on

 * to populate itself with rows of data. A reader (an object implementing the

 * {@code RowSetReader} interface) may be registered with

 * a {@code RowSet} object that supports the reader/writer paradigm.

 * When the {@code RowSet} object's {@code execute} method is

 * called, it in turn calls the reader's {@code readData} method.

 *

 * @since 1.4

 */

public interface RowSetReader {

  /**

   * Reads the new contents of the calling {@code RowSet} object.

   * In order to call this method, a {@code RowSet}

   * object must have implemented the {@code RowSetInternal} interface

   * and registered this {@code RowSetReader} object as its reader.

   * The {@code readData}  method is invoked internally

   * by the {@code RowSet.execute} method for rowsets that support the

   * reader/writer paradigm.

   *

   * <P>The {@code readData} method adds rows to the caller.

   * It can be implemented in a wide variety of ways and can even

   * populate the caller with rows from a nonrelational data source.

   * In general, a reader may invoke any of the rowset's methods,

   * with one exception. Calling the method {@code execute} will

   * cause an {@code SQLException} to be thrown

   * because {@code execute} may not be called recursively.  Also,

   * when a reader invokes {@code RowSet} methods, no listeners

   * are notified; that is, no {@code RowSetEvent} objects are

   * generated and no {@code RowSetListener} methods are invoked.

   * This is true because listeners are already being notified by the method

   * {@code execute}.

   *

   * @param caller the {@code RowSet} object (1) that has implemented the

   *         {@code RowSetInternal} interface, (2) with which this reader is

   *        registered, and (3) whose {@code execute} method called this reader

   * @throws SQLException if a database access error occurs or this method

   *         invokes the {@code RowSet.execute} method

   */

  void readData(RowSetInternal caller) throws SQLException;

}