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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * under the terms of the GNU General Public License version 2 only, as
 * 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
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package java.sql;

/**
 * An object that can be used to get information about the types
 * and properties for each parameter marker in a
 * <code>PreparedStatement</code> object. For some queries and driver
 * implementations, the data that would be returned by a <code>ParameterMetaData</code>
 * object may not be available until the <code>PreparedStatement</code> has
 * been executed.
 *<p>
 *Some driver implementations may not be able to provide information about the
 *types and properties for each parameter marker in a <code>CallableStatement</code>
 *object.
 *
 * @since 1.4
 */

public interface ParameterMetaData extends Wrapper {

 /**
 * Retrieves the number of parameters in the <code>PreparedStatement</code>
 * object for which this <code>ParameterMetaData</code> object contains
 * information.
 *
 * @return the number of parameters
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 int getParameterCount() throws SQLException;

 /**
 * Retrieves whether null values are allowed in the designated parameter.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return the nullability status of the given parameter; one of
 * <code>ParameterMetaData.parameterNoNulls</code>,
 * <code>ParameterMetaData.parameterNullable</code>, or
 * <code>ParameterMetaData.parameterNullableUnknown</code>
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 int isNullable(int param) throws SQLException;

 /**
 * The constant indicating that a
 * parameter will not allow <code>NULL</code> values.
 */
 int parameterNoNulls = 0;

 /**
 * The constant indicating that a
 * parameter will allow <code>NULL</code> values.
 */
 int parameterNullable = 1;

 /**
 * The constant indicating that the
 * nullability of a parameter is unknown.
 */
 int parameterNullableUnknown = 2;

 /**
 * Retrieves whether values for the designated parameter can be signed numbers.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return <code>true</code> if so; <code>false</code> otherwise
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 boolean isSigned(int param) throws SQLException;

 /**
 * Retrieves the designated parameter's specified column size.
 *
 * <P>The returned value represents the maximum column size for the given parameter.
 * For numeric data, this is the maximum precision. For character data, this is the length in characters.
 * For datetime datatypes, this is the length in characters of the String representation (assuming the
 * maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes. For the ROWID datatype,
 * this is the length in bytes. 0 is returned for data types where the
 * column size is not applicable.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return precision
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 int getPrecision(int param) throws SQLException;

 /**
 * Retrieves the designated parameter's number of digits to right of the decimal point.
 * 0 is returned for data types where the scale is not applicable.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return scale
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 int getScale(int param) throws SQLException;

 /**
 * Retrieves the designated parameter's SQL type.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return SQL type from <code>java.sql.Types</code>
 * @exception SQLException if a database access error occurs
 * @since 1.4
 * @see Types
 */
 int getParameterType(int param) throws SQLException;

 /**
 * Retrieves the designated parameter's database-specific type name.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return type the name used by the database. If the parameter type is
 * a user-defined type, then a fully-qualified type name is returned.
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 String getParameterTypeName(int param) throws SQLException;


 /**
 * Retrieves the fully-qualified name of the Java class whose instances
 * should be passed to the method <code>PreparedStatement.setObject</code>.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return the fully-qualified name of the class in the Java programming
 * language that would be used by the method
 * <code>PreparedStatement.setObject</code> to set the value
 * in the specified parameter. This is the class name used
 * for custom mapping.
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 String getParameterClassName(int param) throws SQLException;

 /**
 * The constant indicating that the mode of the parameter is unknown.
 */
 int parameterModeUnknown = 0;

 /**
 * The constant indicating that the parameter's mode is IN.
 */
 int parameterModeIn = 1;

 /**
 * The constant indicating that the parameter's mode is INOUT.
 */
 int parameterModeInOut = 2;

 /**
 * The constant indicating that the parameter's mode is OUT.
 */
 int parameterModeOut = 4;

 /**
 * Retrieves the designated parameter's mode.
 *
 * @param param the first parameter is 1, the second is 2, ...
 * @return mode of the parameter; one of
 * <code>ParameterMetaData.parameterModeIn</code>,
 * <code>ParameterMetaData.parameterModeOut</code>, or
 * <code>ParameterMetaData.parameterModeInOut</code>
 * <code>ParameterMetaData.parameterModeUnknown</code>.
 * @exception SQLException if a database access error occurs
 * @since 1.4
 */
 int getParameterMode(int param) throws SQLException;
}