xdev.db

Class Result

java.lang.Object

xdev.db.Result

All Implemented Interfaces:

AutoCloseable

Direct Known Subclasses:

DelegatingResult, JDBCResult, PrefetchedResult, ServletResult

public abstract class Result
extends Object
implements AutoCloseable

A table of data representing a database result set, which is usually generated by executing a statement that queries the database.

A Result object maintains a cursor pointing to its current row of data. Initially the cursor is positioned before the first row. The next() method moves the cursor to the next row, and because it returns false when there are no more rows in the Result object, it can be used in a while loop to iterate through the result set.

The Result interface provides getter methods (getInt(int), getString(int) , and so on) for retrieving column values from the current row. Values can be retrieved using either the index number of the column or the name of the column. In general, using the column index will be more efficient. Columns are numbered from 0. For maximum portability, result set columns within each row should be read in left-to-right order, and each column should be read only once. For the getter methods, a driver attempts to convert the underlying data to the Java type specified in the getter method and returns a suitable Java value.

Column names used as input to getter methods are case insensitive. When a getter method is called with a column name and several columns have the same name, the value of the first matching column will be returned. The column name option is designed to be used when column names are used in the SQL query that generated the result set. For columns that are NOT explicitly named in the query, it is best to use column numbers. If column names are used, the programmer should take care to guarantee that they uniquely refer to the intended columns, which can be assured with the SQL AS clause.

The number, types and properties of a Results object's column are provided by the ColumnMetaData object returned by the getMetadata(int) method.

Author:

XDEV Software

Constructor Summary

Constructors

Constructor and Description
Result()

Method Summary

Modifier and Type	Method and Description
abstract void	close() Closes this Result and releases all used resources.
void	dump() Prints the contents of this result to System.out.
void	dump(PrintStream out) Prints the contents of this result to out.
boolean	getBoolean(int col) Gets the value of the designated column in the current row of this Result object as an boolean.
boolean	getBoolean(int col, boolean defaultValue) Gets the value of the designated column in the current row of this Result object as an boolean.
boolean	getBoolean(String colName) Gets the value of the designated column in the current row of this Result object as an boolean.
boolean	getBoolean(String colName, boolean defaultValue) Gets the value of the designated column in the current row of this Result object as an boolean.
byte	getByte(int col) Gets the value of the designated column in the current row of this Result object as an byte.
byte	getByte(int col, byte defaultValue) Gets the value of the designated column in the current row of this Result object as an byte.
byte	getByte(String colName) Gets the value of the designated column in the current row of this Result object as an byte.
byte	getByte(String colName, byte defaultValue) Gets the value of the designated column in the current row of this Result object as an byte.
abstract int	getColumnCount() Returns the number of columns.
int	getColumnIndex(String colName) Returns the index of the column with the specified name.
DBDataSource	getDataSource() Gets the DBDataSource of this Result.
double	getDouble(int col) Gets the value of the designated column in the current row of this Result object as an double.
double	getDouble(int col, double defaultValue) Gets the value of the designated column in the current row of this Result object as an double.
double	getDouble(String colName) Gets the value of the designated column in the current row of this Result object as an double.
double	getDouble(String colName, double defaultValue) Gets the value of the designated column in the current row of this Result object as an double.
float	getFloat(int col) Gets the value of the designated column in the current row of this Result object as an float.
float	getFloat(int col, float defaultValue) Gets the value of the designated column in the current row of this Result object as an float.
float	getFloat(String colName) Gets the value of the designated column in the current row of this Result object as an float.
float	getFloat(String colName, float defaultValue) Gets the value of the designated column in the current row of this Result object as an float.
int	getInt(int col) Gets the value of the designated column in the current row of this Result object as an int.
int	getInt(int col, int defaultValue) Gets the value of the designated column in the current row of this Result object as an int.
int	getInt(String colName) Gets the value of the designated column in the current row of this Result object as an int.
int	getInt(String colName, int defaultValue) Gets the value of the designated column in the current row of this Result object as an int.
long	getLong(int col) Gets the value of the designated column in the current row of this Result object as an long.
long	getLong(int col, long defaultValue) Gets the value of the designated column in the current row of this Result object as an long.
long	getLong(String colName) Gets the value of the designated column in the current row of this Result object as an long.
long	getLong(String colName, long defaultValue) Gets the value of the designated column in the current row of this Result object as an long.
Integer	getMaxRowCount() Returns the maxRowCount for this Result.
abstract ColumnMetaData	getMetadata(int col) Returns the cached ColumnMetadata for the column with index col.
abstract Object	getObject(int col) Gets the value of the designated column in the current row of this Result object as an Object.
Object	getObject(String colName) Gets the value of the designated column in the current row of this Result object as an Object.
QueryInfo	getQueryInfo() Gets the QueryInfo of this Result.
short	getShort(int col) Gets the value of the designated column in the current row of this Result object as an short.
short	getShort(int col, short defaultValue) Gets the value of the designated column in the current row of this Result object as an short.
short	getShort(String colName) Gets the value of the designated column in the current row of this Result object as an short.
short	getShort(String colName, short defaultValue) Gets the value of the designated column in the current row of this Result object as an short.
String	getString(int col) Gets the value of the designated column in the current row of this Result object as an String.
String	getString(int col, String defaultValue) Gets the value of the designated column in the current row of this Result object as an String.
String	getString(String colName) Gets the value of the designated column in the current row of this Result object as an String.
String	getString(String colName, String defaultValue) Gets the value of the designated column in the current row of this Result object as an String.
abstract boolean	next()
void	setDataSource(DBDataSource dataSource) Sets the dataSource for this Result.
void	setMaxRowCount(Integer maxRowCount) Sets the maxRowCount for this Result instance, null means not specified.
void	setQueryInfo(QueryInfo queryInfo) Sets the queryInfo for this Result.
abstract int	skip(int count) Skips over the specified count of rows.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Result

public Result()

Method Detail

setDataSource

public void setDataSource(DBDataSource dataSource)

Sets the dataSource for this Result.

Parameters:

dataSource - the DBDataSource of this Result

getDataSource

public DBDataSource getDataSource()

Gets the DBDataSource of this Result.

Returns:

the DBDataSource of this Result

setQueryInfo

public void setQueryInfo(QueryInfo queryInfo)

Sets the queryInfo for this Result.

Parameters:

queryInfo - the QueryInfo of this Result

getQueryInfo

public QueryInfo getQueryInfo()

Gets the QueryInfo of this Result.

Returns:

the QueryInfo of this Result

setMaxRowCount

public void setMaxRowCount(Integer maxRowCount)

Sets the maxRowCount for this Result instance, null means not specified.

Parameters:

maxRowCount -

getMaxRowCount

public Integer getMaxRowCount()

Returns the maxRowCount for this Result.

Returns:

the maxRowCount for this Result instance or null if none has been specified.

getColumnCount

public abstract int getColumnCount()

Returns the number of columns.

Returns:

the number of columns as int value.

getMetadata

public abstract ColumnMetaData getMetadata(int col)

Returns the cached ColumnMetadata for the column with index col.

Note that col starts with 0 for the first column.

Parameters:

col - the index of the column whose ColumnMetadata shall be returned, starting at 0

Returns:

the cached ColumnMetadata of the column with index col

next

public abstract boolean next()
                      throws DBException

Returns:

true if there is another row to be returned, otherwise false.

Throws:

DBException - if any error occurred.

skip

public abstract int skip(int count)
                  throws DBException

Skips over the specified count of rows.

The skip method may, for a variety of reasons, end up skipping over some smaller number of rows, possibly 0. This may be caused by reaching the end of the result.

Parameters:

count - the number of rows to skip

Returns:

the actual number of rows skipped

Throws:

DBException - if any error occured

getObject

public abstract Object getObject(int col)
                          throws DBException

Gets the value of the designated column in the current row of this Result object as an Object.

Parameters:

col - the index of the column

Returns:

a java.lang.Object holding the column value

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

getObject

public Object getObject(String colName)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an Object.

Parameters:

colName - the name of the column

Returns:

a java.lang.Object holding the column value

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

getColumnIndex

public int getColumnIndex(String colName)
                   throws DBException

Returns the index of the column with the specified name.

Parameters:

colName - as a String

Returns:

the index for the specified column as int value

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

getString

public String getString(int col)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an String.

Parameters:

col - the index of the column

Returns:

a String holding the column value

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

See Also:

getString(int, String)

getString

public String getString(int col,
                        String defaultValue)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an String.

Parameters:

col - the index of the column

defaultValue - the default String

Returns:

a String holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

See Also:

getObject(int)

getString

public String getString(String colName)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an String.

Parameters:

colName - the name of the column

Returns:

a String holding the column value

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

getString

public String getString(String colName,
                        String defaultValue)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an String.

Parameters:

colName - the name of the column

defaultValue - the default String

Returns:

a String holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs.

See Also:

getColumnIndex(String), getString(int, String)

getByte

public byte getByte(int col)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an byte.

Parameters:

col - the index of the column

Returns:

a byte holding the column value; If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getByte(int, byte)

getByte

public byte getByte(int col,
                    byte defaultValue)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an byte.

Parameters:

col - the index of the column

defaultValue - the default byte

Returns:

a byte holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getByte

public byte getByte(String colName)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an byte.

Parameters:

colName - the name of the column

Returns:

a byte holding the column value; If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getByte(int)

getByte

public byte getByte(String colName,
                    byte defaultValue)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an byte.

Parameters:

colName - the name of the column

defaultValue - the default byte

Returns:

a byte holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getByte(int, byte)

getShort

public short getShort(int col)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an short.

Parameters:

col - the index of the column

Returns:

a short holding the column value; If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getShort(int, short)

getShort

public short getShort(int col,
                      short defaultValue)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an short.

Parameters:

col - the index of the column

defaultValue - the default byte

Returns:

a short holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getShort

public short getShort(String colName)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an short.

Parameters:

colName - the name of the column

Returns:

a short holding the column value; If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getShort(int)

getShort

public short getShort(String colName,
                      short defaultValue)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an short.

Parameters:

colName - the name of the column

defaultValue - the default short

Returns:

a short holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getShort(int, short)

getInt

public int getInt(int col)
           throws DBException

Gets the value of the designated column in the current row of this Result object as an int.

Parameters:

col - the index of the column

Returns:

a int holding the column value. If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getInt(int, int)

getInt

public int getInt(int col,
                  int defaultValue)
           throws DBException

Gets the value of the designated column in the current row of this Result object as an int.

Parameters:

col - the index of the column

defaultValue - the default int

Returns:

a int holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getInt

public int getInt(String colName)
           throws DBException

Gets the value of the designated column in the current row of this Result object as an int.

Parameters:

colName - the name of the column

Returns:

a int holding the column value. If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getInt(int)

getInt

public int getInt(String colName,
                  int defaultValue)
           throws DBException

Gets the value of the designated column in the current row of this Result object as an int.

Parameters:

colName - the name of the column

defaultValue - the default int

Returns:

a int holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getInt(int, int)

getLong

public long getLong(int col)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an long.

Parameters:

col - the index of the column

Returns:

a long holding the column value. If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getLong(int, long)

getLong

public long getLong(int col,
                    long defaultValue)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an long.

Parameters:

col - the index of the column

defaultValue - the default long

Returns:

a long holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getLong

public long getLong(String colName)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an long.

Parameters:

colName - the name of the column

Returns:

a long holding the column value. If the column value is null, 0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getLong(int)

getLong

public long getLong(String colName,
                    long defaultValue)
             throws DBException

Gets the value of the designated column in the current row of this Result object as an long.

Parameters:

colName - the name of the column

defaultValue - the default long

Returns:

a long holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getLong(int, long)

getFloat

public float getFloat(int col)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an float.

Parameters:

col - the index of the column

Returns:

a float holding the column value. If the column value is null, 0f is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getFloat(int, float)

getFloat

public float getFloat(int col,
                      float defaultValue)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an float.

Parameters:

col - the index of the column

defaultValue - the default float

Returns:

a float holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getFloat

public float getFloat(String colName)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an float.

Parameters:

colName - the name of the column

Returns:

a float holding the column value. If the column value is null, 0f is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getFloat(int)

getFloat

public float getFloat(String colName,
                      float defaultValue)
               throws DBException

Gets the value of the designated column in the current row of this Result object as an float.

Parameters:

colName - the name of the column

defaultValue - the default float

Returns:

a float holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getFloat(int, float)

getDouble

public double getDouble(int col)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an double.

Parameters:

col - the index of the column

Returns:

a double holding the column value. If the column value is null, 0.0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getDouble(int, double)

getDouble

public double getDouble(int col,
                        double defaultValue)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an double.

Parameters:

col - the index of the column

defaultValue - the default double

Returns:

a double holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getDouble

public double getDouble(String colName)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an double.

Parameters:

colName - the name of the column

Returns:

a double holding the column value. If the column value is null, 0.0 is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

getDouble

public double getDouble(String colName,
                        double defaultValue)
                 throws DBException

Gets the value of the designated column in the current row of this Result object as an double.

Parameters:

colName - the name of the column

defaultValue - the default double

Returns:

a double holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getDouble(int, double)

getBoolean

public boolean getBoolean(int col)
                   throws DBException

Gets the value of the designated column in the current row of this Result object as an boolean.

Parameters:

col - the index of the column

Returns:

a boolean holding the column value. If the column value is null, false is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getBoolean(int, boolean)

getBoolean

public boolean getBoolean(int col,
                          boolean defaultValue)
                   throws DBException

Gets the value of the designated column in the current row of this Result object as an boolean.

Parameters:

col - the index of the column

defaultValue - the default boolean

Returns:

a boolean holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getObject(int)

getBoolean

public boolean getBoolean(String colName)
                   throws DBException

Gets the value of the designated column in the current row of this Result object as an boolean.

Parameters:

colName - the name of the column

Returns:

a boolean holding the column value. If the column value is null, false is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getBoolean(int)

getBoolean

public boolean getBoolean(String colName,
                          boolean defaultValue)
                   throws DBException

Gets the value of the designated column in the current row of this Result object as an boolean.

Parameters:

colName - the name of the column

defaultValue - the default boolean

Returns:

a boolean holding the column value, if the column value is null the defaultValue is returned.

Throws:

DBException - if the columnIndex is not valid; if a database access error occurs or the value can not be cast.

See Also:

getColumnIndex(String), getBoolean(int, boolean)

close

public abstract void close()
                    throws DBException

Closes this Result and releases all used resources.

Specified by:

close in interface AutoCloseable

Throws:

DBException - if a database access error occurs.

dump

public void dump()
          throws DBException

Prints the contents of this result to System.out.

Throws:

DBException

Since:

3.1

dump

public void dump(PrintStream out)
          throws DBException

Prints the contents of this result to out.

Parameters:

out - the stream to print to

Throws:

DBException

Since:

3.1