?? resultsetmetadata.java
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/*
Copyright (C) 2002 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.mysql.jdbc;
import java.sql.SQLException;
import java.sql.Types;
/**
* A ResultSetMetaData object can be used to find out about the types and
* properties of the columns in a ResultSet
*
* @see java.sql.ResultSetMetaData
* @author Mark Matthews
* @version $Id: ResultSetMetaData.java,v 1.12.2.6 2004/02/18 16:04:58 mmatthew Exp $
*/
public class ResultSetMetaData implements java.sql.ResultSetMetaData {
Field[] fields;
/**
* Initialise for a result with a tuple set and
* a field descriptor set
*
* @param fields the array of field descriptors
*/
public ResultSetMetaData(Field[] fields) {
this.fields = fields;
}
/**
* Is the column automatically numbered (and thus read-only)
*
* MySQL Auto-increment columns are not read only,
* so to conform to the spec, this method returns false.
*
* @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 isAutoIncrement(int column) throws java.sql.SQLException {
Field f = getField(column);
return f.isAutoIncrement();
}
/**
* Does a column's case matter? ASSUMPTION: Any field that is
* not obviously case insensitive is assumed to be case sensitive
*
* @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 isCaseSensitive(int column) throws java.sql.SQLException {
Field field = getField(column);
int sqlType = field.getSQLType();
switch (sqlType) {
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.DATE:
case Types.TIME:
case Types.TIMESTAMP:
return false;
case Types.CHAR:
case Types.VARCHAR:
return field.isBinary();
default:
return true;
}
}
/**
* What's a column's table's catalog name?
*
* @param column the first column is 1, the second is 2...
* @return catalog name, or "" if not applicable
* @throws java.sql.SQLException if a database access error occurs
*/
public String getCatalogName(int column) throws java.sql.SQLException {
Field f = getField(column);
String database = f.getDatabaseName();
return (database == null) ? "" : database;
}
//--------------------------JDBC 2.0-----------------------------------
/**
* JDBC 2.0
*
* <p>Return the fully qualified name of the Java class whose instances
* are manufactured if ResultSet.getObject() is called to retrieve a value
* from the column. ResultSet.getObject() may return a subClass of the
* class returned by this method.
*
* @param column the column number to retrieve information for
* @return the fully qualified name of the Java class whose instances
* are manufactured if ResultSet.getObject() is called to retrieve a value
* from the column.
*
* @throws SQLException if an error occurs
*/
public String getColumnClassName(int column) throws SQLException {
Field f = getField(column);
// From JDBC-3.0 spec
//
// JDBC Type Java Object Type
//
// CHAR String
// VARCHAR String
// LONGVARCHAR String
// NUMERIC java.math.BigDecimal
// DECIMAL java.math.BigDecimal
// BIT Boolean
// BOOLEAN Boolean
// TINYINT Integer
// SMALLINT Integer
// INTEGER Integer
// BIGINT Long
// REAL Float
// FLOAT Double
// DOUBLE Double
// BINARY byte[]
// VARBINARY byte[]
// LONGVARBINARY byte[]
// DATE java.sql.Date
// TIME java.sql.Time
// TIMESTAMP java.sql.Timestamp
// DISTINCT Object type of underlying type
// CLOB Clob
// BLOB Blob
// ARRAY Array
// STRUCT Struct or SQLData
// REF Ref
// DATALINK java.net.URL
// JAVA_OBJECT underlying Java class
switch (f.getSQLType()) {
case Types.BIT:
case Types.BOOLEAN:
return "java.lang.Boolean";
case Types.TINYINT:
return "java.lang.Integer";
case Types.SMALLINT:
return "java.lang.Integer";
case Types.INTEGER:
if (f.isUnsigned()) {
return "java.lang.Long";
} else {
return "java.lang.Integer";
}
case Types.BIGINT:
return "java.lang.Long";
case Types.DECIMAL:
case Types.NUMERIC:
return "java.math.BigDecimal";
case Types.REAL:
return "java.lang.Float";
case Types.FLOAT:
case Types.DOUBLE:
return "java.lang.Double";
case Types.CHAR:
case Types.VARCHAR:
case Types.LONGVARCHAR:
return "java.lang.String";
case Types.BINARY:
case Types.VARBINARY:
case Types.LONGVARBINARY:
if (!f.isBlob()) {
return "java.lang.String";
} else if (!f.isBinary()) {
return "java.lang.String";
} else {
return "[B";
}
case Types.DATE:
return "java.sql.Date";
case Types.TIME:
return "java.sql.Time";
case Types.TIMESTAMP:
return "java.sql.Timestamp";
default:
return "java.lang.Object";
}
}
/**
* Whats the number of columns in the ResultSet?
*
* @return the number
* @throws java.sql.SQLException if a database access error occurs
*/
public int getColumnCount() throws java.sql.SQLException {
return fields.length;
}
/**
* What is the column's normal maximum width in characters?
*
* @param column the first column is 1, the second is 2, etc.
* @return the maximum width
* @throws java.sql.SQLException if a database access error occurs
*/
public int getColumnDisplaySize(int column) throws java.sql.SQLException {
return getField(column).getLength();
}
/**
* What is the suggested column title for use in printouts and
* displays?
*
* @param column the first column is 1, the second is 2, etc.
* @return the column label
* @throws java.sql.SQLException if a database access error occurs
*/
public String getColumnLabel(int column) throws java.sql.SQLException {
return getColumnName(column);
}
/**
* What's a column's name?
*
* @param column the first column is 1, the second is 2, etc.
* @return the column name
* @throws java.sql.SQLException if a databvase access error occurs
*/
public String getColumnName(int column) throws java.sql.SQLException {
return getField(column).getName();
}
/**
* What is a column's SQL Type? (java.sql.Type int)
*
* @param column the first column is 1, the second is 2, etc.
* @return the java.sql.Type value
* @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
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