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

 *

 * This code is free software; you can redistribute it and/or modify it

 * 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;

}