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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 of the columns in a <code>ResultSet</code> object.
   * The following code fragment creates the <code>ResultSet</code> object rs,
   * creates the <code>ResultSetMetaData</code> object rsmd, and uses rsmd
   * to find out how many columns rs has and whether the first column in rs
   * can be used in a <code>WHERE</code> clause.
   * <PRE>
   *
   *     ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
   *     ResultSetMetaData rsmd = rs.getMetaData();
   *     int numberOfColumns = rsmd.getColumnCount();
   *     boolean b = rsmd.isSearchable(1);
   *
   * </PRE>
   */
  
  public interface ResultSetMetaData extends Wrapper {
  
      /**
       * Returns the number of columns in this <code>ResultSet</code> object.
       *
       * @return the number of columns
       * @exception SQLException if a database access error occurs
       */
      int getColumnCount() throws SQLException;
  
      /**
       * Indicates whether the designated column is automatically numbered.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isAutoIncrement(int column) throws SQLException;
  
      /**
       * Indicates whether a column's case matters.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isCaseSensitive(int column) throws SQLException;
  
      /**
       * Indicates whether the designated column can be used in a where clause.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isSearchable(int column) throws SQLException;
  
      /**
       * Indicates whether the designated column is a cash value.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isCurrency(int column) throws SQLException;
  
      /**
       * Indicates the nullability of values in the designated column.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return the nullability status of the given column; one of <code>columnNoNulls</code>,
       *          <code>columnNullable</code> or <code>columnNullableUnknown</code>
       * @exception SQLException if a database access error occurs
       */
      int isNullable(int column) throws SQLException;
  
      /**
       * The constant indicating that a
       * column does not allow <code>NULL</code> values.
       */
      int columnNoNulls = 0;
  
      /**
       * The constant indicating that a
       * column allows <code>NULL</code> values.
       */
      int columnNullable = 1;
  
      /**
       * The constant indicating that the
       * nullability of a column's values is unknown.
       */
      int columnNullableUnknown = 2;
  
      /**
       * Indicates whether values in the designated column are signed numbers.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isSigned(int column) throws SQLException;
  
      /**
       * Indicates the designated column's normal maximum width in characters.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return the normal maximum number of characters allowed as the width
       *          of the designated column
       * @exception SQLException if a database access error occurs
       */
      int getColumnDisplaySize(int column) throws SQLException;
  
      /**
       * Gets the designated column's suggested title for use in printouts and
       * displays. The suggested title is usually specified by the SQL <code>AS</code>
       * clause.  If a SQL <code>AS</code> is not specified, the value returned from
       * <code>getColumnLabel</code> will be the same as the value returned by the
       * <code>getColumnName</code> method.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return the suggested column title
       * @exception SQLException if a database access error occurs
       */
      String getColumnLabel(int column) throws SQLException;
  
      /**
       * Get the designated column's name.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return column name
       * @exception SQLException if a database access error occurs
       */
      String getColumnName(int column) throws SQLException;
  
      /**
       * Get the designated column's table's schema.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return schema name or "" if not applicable
       * @exception SQLException if a database access error occurs
       */
      String getSchemaName(int column) throws SQLException;
  
      /**
       * Get the designated column's specified column size.
       * 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 column the first column is 1, the second is 2, ...
       * @return precision
       * @exception SQLException if a database access error occurs
       */
      int getPrecision(int column) throws SQLException;
  
      /**
       * Gets the designated column's number of digits to right of the decimal point.
       * 0 is returned for data types where the scale is not applicable.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return scale
       * @exception SQLException if a database access error occurs
       */
      int getScale(int column) throws SQLException;
  
      /**
       * Gets the designated column's table name.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return table name or "" if not applicable
       * @exception SQLException if a database access error occurs
       */
      String getTableName(int column) throws SQLException;
  
      /**
       * Gets the designated column's table's catalog name.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return the name of the catalog for the table in which the given column
       *          appears or "" if not applicable
       * @exception SQLException if a database access error occurs
       */
      String getCatalogName(int column) throws SQLException;
  
      /**
       * Retrieves the designated column's SQL type.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return SQL type from java.sql.Types
       * @exception SQLException if a database access error occurs
       * @see Types
       */
      int getColumnType(int column) throws SQLException;
  
      /**
       * Retrieves the designated column's database-specific type name.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return type name used by the database. If the column type is
       * a user-defined type, then a fully-qualified type name is returned.
       * @exception SQLException if a database access error occurs
       */
      String getColumnTypeName(int column) throws SQLException;
  
      /**
       * Indicates whether the designated column is definitely not writable.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isReadOnly(int column) throws SQLException;
  
      /**
       * Indicates whether it is possible for a write on the designated column to succeed.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isWritable(int column) throws SQLException;
  
      /**
       * Indicates whether a write on the designated column will definitely succeed.
       *
       * @param column the first column is 1, the second is 2, ...
       * @return <code>true</code> if so; <code>false</code> otherwise
       * @exception SQLException if a database access error occurs
       */
      boolean isDefinitelyWritable(int column) throws SQLException;
  
      //--------------------------JDBC 2.0-----------------------------------
  
      /**
       * <p>Returns the fully-qualified name of the Java class whose instances
       * are manufactured if the method <code>ResultSet.getObject</code>
       * is called to retrieve a value
       * from the column.  <code>ResultSet.getObject</code> may return a subclass of the
       * class returned by this method.
       *
       * @param column the first column 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>ResultSet.getObject</code> to retrieve the value in the specified
       * column. This is the class name used for custom mapping.
       * @exception SQLException if a database access error occurs
       * @since 1.2
       */
      String getColumnClassName(int column) throws SQLException;
  }
  