resultsetmetadata.java

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     * @throws java.sql.SQLException if a database access error occurs
     * @see java.sql.Types
     */
    public int getColumnType(int column) throws java.sql.SQLException {
        return getField(column).getSQLType();
    }

    /**
     * Whats is the column's data source specific type name?
     *
     * @param column the first column is 1, the second is 2, etc.
     * @return the type name
     * @throws java.sql.SQLException if a database access error occurs
     */
    public String getColumnTypeName(int column) throws java.sql.SQLException {
    	Field field = getField(column);
    	
        int mysqlType = field.getMysqlType();

        switch (mysqlType) {
        case MysqlDefs.FIELD_TYPE_DECIMAL:
            return field.isUnsigned() ? "DECIMAL UNSIGNED" : "DECIMAL";

        case MysqlDefs.FIELD_TYPE_TINY:
            return field.isUnsigned() ? "TINYINT UNSIGNED" : "TINYINT";

        case MysqlDefs.FIELD_TYPE_SHORT:
            return field.isUnsigned() ? "SMALLINT UNSIGNED" : "SMALLINT";

        case MysqlDefs.FIELD_TYPE_LONG:
            return field.isUnsigned() ? "INTEGER UNSIGNED" : "INTEGER";

        case MysqlDefs.FIELD_TYPE_FLOAT:
            return field.isUnsigned() ? "FLOAT UNSIGNED" : "FLOAT";

        case MysqlDefs.FIELD_TYPE_DOUBLE:
            return field.isUnsigned() ? "DOUBLE UNSIGNED" : "DOUBLE";

        case MysqlDefs.FIELD_TYPE_NULL:
            return "NULL";

        case MysqlDefs.FIELD_TYPE_TIMESTAMP:
            return "TIMESTAMP";

        case MysqlDefs.FIELD_TYPE_LONGLONG:
            return field.isUnsigned() ? "BIGINT UNSIGNED" : "BIGINT";

        case MysqlDefs.FIELD_TYPE_INT24:
            return field.isUnsigned() ? "MEDIUMINT UNSIGNED" : "MEDIUMINT";

        case MysqlDefs.FIELD_TYPE_DATE:
            return "DATE";

        case MysqlDefs.FIELD_TYPE_TIME:
            return "TIME";

        case MysqlDefs.FIELD_TYPE_DATETIME:
            return "DATETIME";

        case MysqlDefs.FIELD_TYPE_TINY_BLOB:
            return "TINYBLOB";

        case MysqlDefs.FIELD_TYPE_MEDIUM_BLOB:
            return "MEDIUMBLOB";

        case MysqlDefs.FIELD_TYPE_LONG_BLOB:
            return "LONGBLOB";

        case MysqlDefs.FIELD_TYPE_BLOB:

            if (getField(column).isBinary()) {
                return "BLOB";
            } else {
                return "TEXT";
            }

        case MysqlDefs.FIELD_TYPE_VAR_STRING:
            return "VARCHAR";

        case MysqlDefs.FIELD_TYPE_STRING:
            return "CHAR";

        case MysqlDefs.FIELD_TYPE_ENUM:
            return "ENUM";

        case MysqlDefs.FIELD_TYPE_SET:
            return "SET";
           
        case MysqlDefs.FIELD_TYPE_YEAR:
        	return "YEAR";

        default:
            return "UNKNOWN";
        }
    }

    /**
     * Is the column a cash value?
     *
     * @param column the first column is 1, the second is 2...
     * @return true if its a cash column
     * @throws java.sql.SQLException if a database access error occurs
     */
    public boolean isCurrency(int column) throws java.sql.SQLException {
        return false;
    }

    /**
     * Will a write on this column definately succeed?
     *
     * @param column the first column is 1, the second is 2, etc..
     * @return true if so
     * @throws java.sql.SQLException if a database access error occurs
     */
    public boolean isDefinitelyWritable(int column)
        throws java.sql.SQLException {
        return isWritable(column);
    }

    /**
     * Can you put a NULL in this column?
     *
     * @param column the first column is 1, the second is 2...
     * @return one of the columnNullable values
     * @throws java.sql.SQLException if a database access error occurs
     */
    public int isNullable(int column) throws java.sql.SQLException {
        if (!getField(column).isNotNull()) {
            return java.sql.ResultSetMetaData.columnNullable;
        } else {
            return java.sql.ResultSetMetaData.columnNoNulls;
        }
    }

    /**
     * What is a column's number of decimal digits.
     *
     * @param column the first column is 1, the second is 2...
     * @return the precision
     * @throws java.sql.SQLException if a database access error occurs
     */
    public int getPrecision(int column) throws java.sql.SQLException {
        Field f = getField(column);

        if (isDecimalType(f.getSQLType())) {
            if (f.getDecimals() > 0) {
                return (int)(f.getLength() - 1 + f.getPrecisionAdjustFactor());
            }

            return (int)(f.getLength() + f.getPrecisionAdjustFactor());
        }

        switch (f.getMysqlType()) {
        case MysqlDefs.FIELD_TYPE_TINY_BLOB:
        case MysqlDefs.FIELD_TYPE_BLOB:
        case MysqlDefs.FIELD_TYPE_MEDIUM_BLOB:
        case MysqlDefs.FIELD_TYPE_LONG_BLOB:
        	return (int)f.getLength(); // this may change in the future
                                  // for now, the server only
                                  // returns FIELD_TYPE_BLOB for _all_
                                  // BLOB types, but varying lengths
                                  // indicating the _maximum_ size
                                  // for each BLOB type.
        default:
        	return (int)f.getLength();
                
        }
    }

    /**
     * Is the column definitely not writable?
     *
     * @param column the first column is 1, the second is 2, etc.
     * @return true if so
     * @throws java.sql.SQLException if a database access error occurs
     */
    public boolean isReadOnly(int column) throws java.sql.SQLException {
        return getField(column).isReadOnly();
    }

    /**
     * What is a column's number of digits to the right of the
     * decimal point?
     *
     * @param column the first column is 1, the second is 2...
     * @return the scale
     * @throws java.sql.SQLException if a database access error occurs
     */
    public int getScale(int column) throws java.sql.SQLException {
        Field f = getField(column);

        if (isDecimalType(f.getSQLType())) {
            return f.getDecimals();
        }

        return 0;
    }

    /**
     * What is a column's table's schema?  This relies on us knowing
     * the table name.
     *
     * The JDBC specification allows us to return "" if this is not
     * applicable.
     *
     * @param column the first column is 1, the second is 2...
     * @return the Schema
     * @throws java.sql.SQLException if a database access error occurs
     */
    public String getSchemaName(int column) throws java.sql.SQLException {
        return "";
    }

    /**
     * Can the column be used in a WHERE clause?  Basically for
     * this, I split the functions into two types: recognised
     * types (which are always useable), and OTHER types (which
     * may or may not be useable).  The OTHER types, for now, I
     * will assume they are useable.  We should really query the
     * catalog to see if they are useable.
     *
     * @param column the first column is 1, the second is 2...
     * @return true if they can be used in a WHERE clause
     * @throws java.sql.SQLException if a database access error occurs
     */
    public boolean isSearchable(int column) throws java.sql.SQLException {
        return true;
    }

    /**
     * Is the column a signed number?
     *
     * @param column the first column is 1, the second is 2...
     * @return true if so
     * @throws java.sql.SQLException if a database access error occurs
     */
    public boolean isSigned(int column) throws java.sql.SQLException {
        Field f = getField(column);
        int sqlType = f.getSQLType();

        switch (sqlType) {
        case Types.TINYINT:
        case Types.SMALLINT:
        case Types.INTEGER:
        case Types.BIGINT:
        case Types.FLOAT:
        case Types.REAL:
        case Types.DOUBLE:
        case Types.NUMERIC:
        case Types.DECIMAL:
            return !f.isUnsigned();

        case Types.DATE:
        case Types.TIME:
        case Types.TIMESTAMP:
            return false;

        default:
            return false;
        }
    }

    /**
     * Whats a column's table's name?
     *
     * @param column the first column is 1, the second is 2...
     * @return column name, or "" if not applicable
     * @throws java.sql.SQLException if a database access error occurs
     */
    public String getTableName(int column) throws java.sql.SQLException {
        return getField(column).getTableName();
    }

    /**
     * Is it possible for a write on the column to succeed?
     *
     * @param column the first column is 1, the second is 2, etc.
     * @return true if so
     * @throws java.sql.SQLException if a database access error occurs
     */
    public boolean isWritable(int column) throws java.sql.SQLException {
        return !isReadOnly(column);
    }

    // *********************************************************************
    //
    //                END OF PUBLIC INTERFACE
    //
    // *********************************************************************

    /**
     * Returns the field instance for the given column index
     *
     * @param columnIndex the column number to retrieve a field instance for
     * @return the field instance for the given column index
     *
     * @throws java.sql.SQLException if an error occurs
     */
    protected Field getField(int columnIndex) throws java.sql.SQLException {
        if ((columnIndex < 1) || (columnIndex > fields.length)) {
            throw new java.sql.SQLException("Column index out of range.",
                SQLError.SQL_STATE_INVALID_COLUMN_NUMBER);
        }

        return fields[columnIndex - 1];
    }

    /**
     * Checks if the SQL Type is a Decimal/Number Type
     * @param type SQL Type
     */
    private static final boolean isDecimalType(int type) {
        switch (type) {
        case Types.BIT:
        case Types.TINYINT:
        case Types.SMALLINT:
        case Types.INTEGER:
        case Types.BIGINT:
        case Types.FLOAT:
        case Types.REAL:
        case Types.DOUBLE:
        case Types.NUMERIC:
        case Types.DECIMAL:
            return true;
        }

        return false;
    }
}