com.arsdigita.acs
Class Selection

java.lang.Object
  |
  +--com.arsdigita.acs.Selection

All Implemented Interfaces:

DataSource, MultiDataSource

public class Selection

extends java.lang.Object

implements MultiDataSource

Represents a generic multiple-row data source pulled in from the database. To ensure scalability of large queries, does not cache any query results. If it's necessary to call the rowcount or seek methods, you should use SeekableSelection instead.

Field Summary

static java.lang.String	cvsId
protected java.lang.String[]	keys
protected com.arsdigita.db.SimpleResultSet	srs The result set that we're managing

Constructor Summary

Selection(java.lang.Object obj)
Casts the given object to SimpleResultSet

Selection(com.arsdigita.db.SimpleResultSet srs)
Creates a new Selection, initialized from a SimpleResultSet.

Method Summary

boolean	contains(java.lang.String column) Returns true if this contains a column named column.
java.lang.String	get(java.lang.String key) Returns the value of the column named by key.
java.lang.String[]	keys() Returns a list of available keys (column names) in the Selection.
boolean	next() Advances to the next row in the data source, if there is one.
int	rowcount() Not implemented by this object.
int	rownum() Returns the current row number in the datasource.
void	seek(int rownum) This object only implements sequential access, so calling seek with any row other than the current row results in a DataSourceException being thrown.

Methods inherited from class java.lang.Object

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

Field Detail

cvsId

public static final java.lang.String cvsId

srs

protected com.arsdigita.db.SimpleResultSet srs

The result set that we're managing

keys

protected java.lang.String[] keys

Constructor Detail

Selection

public Selection(java.lang.Object obj)
          throws java.sql.SQLException

Casts the given object to SimpleResultSet

Selection

public Selection(com.arsdigita.db.SimpleResultSet srs)
          throws java.sql.SQLException

Creates a new Selection, initialized from a SimpleResultSet.

Method Detail

contains

public boolean contains(java.lang.String column)
                 throws DataSourceException

Returns true if this contains a column named column.

Specified by:

contains in interface DataSource

seek

public void seek(int rownum)
          throws DataSourceException

This object only implements sequential access, so calling seek with any row other than the current row results in a DataSourceException being thrown.

Specified by:

seek in interface MultiDataSource

get

public java.lang.String get(java.lang.String key)
                     throws DataSourceException

Returns the value of the column named by key. Returns the empty string if the column value is null.

Specified by:

get in interface DataSource

Throws:

InvalidKeyException - if key is not found.

next

public boolean next()
             throws DataSourceException

Advances to the next row in the data source, if there is one.

Specified by:

next in interface MultiDataSource

Returns:

true; or false if there are no more elements.

keys

public java.lang.String[] keys()
                        throws DataSourceException

Returns a list of available keys (column names) in the Selection.

Specified by:

keys in interface DataSource

rownum

public int rownum()
           throws DataSourceException

Returns the current row number in the datasource.

Specified by:

rownum in interface MultiDataSource

rowcount

public int rowcount()
             throws DataSourceException

Not implemented by this object. A DataSourceException is always thrown.

Specified by:

rowcount in interface MultiDataSource