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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
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*
* 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,
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*
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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;
/**
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