resultsetmetadata.java

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    }

    /**
     * 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 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"; //$NON-NLS-1$
    
        case MysqlDefs.FIELD_TYPE_TIMESTAMP:
            return "TIMESTAMP"; //$NON-NLS-1$       

        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"; //$NON-NLS-1$       

        case MysqlDefs.FIELD_TYPE_TIME:
            return "TIME"; //$NON-NLS-1$       

        case MysqlDefs.FIELD_TYPE_DATETIME:
            return "DATETIME"; //$NON-NLS-1$      

        case MysqlDefs.FIELD_TYPE_TINY_BLOB:
            return "TINYBLOB"; //$NON-NLS-1$
        
        case MysqlDefs.FIELD_TYPE_MEDIUM_BLOB:
            return "MEDIUMBLOB"; //$NON-NLS-1$
    
        case MysqlDefs.FIELD_TYPE_LONG_BLOB:
            return "LONGBLOB"; //$NON-NLS-1$
            
        case MysqlDefs.FIELD_TYPE_BLOB:
            if (getField(column).isBinary()) {
                return "BLOB";//$NON-NLS-1$
            }
            
            return "TEXT";//$NON-NLS-1$
 
        case MysqlDefs.FIELD_TYPE_VARCHAR:
        	return "VARCHAR"; //$NON-NLS-1$
        	
        case MysqlDefs.FIELD_TYPE_VAR_STRING:
            return "VARCHAR"; //$NON-NLS-1$
        
        case MysqlDefs.FIELD_TYPE_STRING:
            return "CHAR"; //$NON-NLS-1$

        case MysqlDefs.FIELD_TYPE_ENUM:
            return "ENUM"; //$NON-NLS-1$
        
        case MysqlDefs.FIELD_TYPE_YEAR:
        	return "YEAR"; //$NON_NLS-1$

        case MysqlDefs.FIELD_TYPE_SET:
            return "SET"; //$NON-NLS-1$
            
        default:
            return "UNKNOWN"; //$NON-NLS-1$
        }
    }

    /**
     * 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 SQLException if a database access error occurs
     */
    public boolean isCurrency(int column) throws 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 SQLException if a database access error occurs
     */
    public boolean isDefinitelyWritable(int column) throws 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 SQLException if a database access error occurs
     */
    public int isNullable(int column) throws SQLException {
        if (!getField(column).isNotNull()) {
            return java.sql.ResultSetMetaData.columnNullable;
        }

        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 SQLException if a database access error occurs
     */
    public int getPrecision(int column) throws SQLException {
        Field f = getField(column);

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

            return 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 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 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 SQLException if a database access error occurs
     */
    public boolean isReadOnly(int column) throws 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 SQLException if a database access error occurs
     */
    public int getScale(int column) throws 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 SQLException if a database access error occurs
     */
    public String getSchemaName(int column) throws SQLException {
        return ""; //$NON-NLS-1$
    }

    /**
     * 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 SQLException if a database access error occurs
     */
    public boolean isSearchable(int column) throws 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 SQLException if a database access error occurs
     */
    public boolean isSigned(int column) throws 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 SQLException if a database access error occurs
     */
    public String getTableName(int column) throws 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 SQLException if a database access error occurs
     */
    public boolean isWritable(int column) throws SQLException {
        return !isReadOnly(column);
    }

    /**
     * Returns a string representation of this object
     *
     * @return ...
     */
    public String toString() {
        StringBuffer toStringBuf = new StringBuffer();
        toStringBuf.append(super.toString());
        toStringBuf.append(" - Field level information: "); //$NON-NLS-1$

        for (int i = 0; i < this.fields.length; i++) {
            toStringBuf.append("\n\t"); //$NON-NLS-1$
            toStringBuf.append(this.fields[i].toString());
        }

        return toStringBuf.toString();
    }

    // *********************************************************************
    //
    //                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 SQLException if an error occurs
     */
    protected Field getField(int columnIndex) throws SQLException {
        if ((columnIndex < 1) || (columnIndex > this.fields.length)) {
            throw new SQLException(Messages.getString("ResultSetMetaData.46"), //$NON-NLS-1$
                SQLError.SQL_STATE_INVALID_COLUMN_NUMBER);
        }

        return this.fields[columnIndex - 1];
    }

    /**
     * Checks if the SQL Type is a Decimal/Number Type
     *
     * @param type SQL Type
     *
     * @return ...
     */
    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;
    }
}