org.apache.commons.beanutils

Class RowSetDynaClass

public class RowSetDynaClass extends JDBCDynaClass implements DynaClass, Serializable

Implementation of {@link DynaClass} that creates an in-memory collection of {@link DynaBean}s representing the results of an SQL query. Once the {@link DynaClass} instance has been created, the JDBC ResultSet and Statement on which it is based can be closed, and the underlying Connection can be returned to its connection pool (if you are using one).

The normal usage pattern is something like:

   Connection conn = ...;  // Acquire connection from pool
   Statement stmt = conn.createStatement();
   ResultSet rs = stmt.executeQuery("SELECT ...");
   RowSetDynaClass rsdc = new RowSetDynaClass(rs);
   rs.close();
   stmt.close();
   ...;                    // Return connection to pool
   List rows = rsdc.getRows();
   ...;                   // Process the rows as desired
 

Each column in the result set will be represented as a {@link DynaBean} property of the corresponding name (optionally forced to lower case for portability). There will be one {@link DynaBean} in the List returned by getRows() for each row in the original ResultSet.

In general, instances of {@link RowSetDynaClass} can be serialized and deserialized, which will automatically include the list of {@link DynaBean}s representing the data content. The only exception to this rule would be when the underlying property values that were copied from the ResultSet originally cannot themselves be serialized. Therefore, a {@link RowSetDynaClass} makes a very convenient mechanism for transporting data sets to remote Java-based application components.

Version: $Revision: 1.9 $ $Date: 2004/02/28 13:18:34 $

Author: Craig R. McClanahan

Field Summary
protected intlimit

Limits the size of the returned list.

protected Listrows

The list of {@link DynaBean}s representing the contents of the original ResultSet on which this {@link RowSetDynaClass} was based.

Constructor Summary
RowSetDynaClass(ResultSet resultSet)

Construct a new {@link RowSetDynaClass} for the specified ResultSet.

RowSetDynaClass(ResultSet resultSet, int limit)

Construct a new {@link RowSetDynaClass} for the specified ResultSet.

RowSetDynaClass(ResultSet resultSet, boolean lowerCase)

Construct a new {@link RowSetDynaClass} for the specified ResultSet.

RowSetDynaClass(ResultSet resultSet, boolean lowerCase, int limit)

Construct a new {@link RowSetDynaClass} for the specified ResultSet.

Method Summary
protected voidcopy(ResultSet resultSet)

Copy the column values for each row in the specified ResultSet into a newly created {@link DynaBean}, and add this bean to the list of {@link DynaBean}s that will later by returned by a call to getRows().

protected DynaBeancreateDynaBean()

Create and return a new {@link DynaBean} instance to be used for representing a row in the underlying result set.

ListgetRows()

Return a List containing the {@link DynaBean}s that represent the contents of each Row from the ResultSet that was the basis of this {@link RowSetDynaClass} instance.

Field Detail

limit

protected int limit

Limits the size of the returned list. The call to getRows() will return at most limit number of rows. If less than or equal to 0, does not limit the size of the result.

rows

protected List rows

The list of {@link DynaBean}s representing the contents of the original ResultSet on which this {@link RowSetDynaClass} was based.

Constructor Detail

RowSetDynaClass

public RowSetDynaClass(ResultSet resultSet)

Construct a new {@link RowSetDynaClass} for the specified ResultSet. The property names corresponding to column names in the result set will be lower cased.

Parameters: resultSet The result set to be wrapped

Throws: NullPointerException if resultSet is null SQLException if the metadata for this result set cannot be introspected

RowSetDynaClass

public RowSetDynaClass(ResultSet resultSet, int limit)

Construct a new {@link RowSetDynaClass} for the specified ResultSet. The property names corresponding to column names in the result set will be lower cased.

If limit is not less than 0, max limit number of rows will be copied into the list.

Parameters: resultSet The result set to be wrapped limit The maximum for the size of the result.

Throws: NullPointerException if resultSet is null SQLException if the metadata for this result set cannot be introspected

RowSetDynaClass

public RowSetDynaClass(ResultSet resultSet, boolean lowerCase)

Construct a new {@link RowSetDynaClass} for the specified ResultSet. The property names corresponding to the column names in the result set will be lower cased or not, depending on the specified lowerCase value.

If limit is not less than 0, max limit number of rows will be copied into the resultset.

Parameters: resultSet The result set to be wrapped lowerCase Should property names be lower cased?

Throws: NullPointerException if resultSet is null SQLException if the metadata for this result set cannot be introspected

RowSetDynaClass

public RowSetDynaClass(ResultSet resultSet, boolean lowerCase, int limit)

Construct a new {@link RowSetDynaClass} for the specified ResultSet. The property names corresponding to the column names in the result set will be lower cased or not, depending on the specified lowerCase value.

WARNING - If you specify false for lowerCase, the returned property names will exactly match the column names returned by your JDBC driver. Because different drivers might return column names in different cases, the property names seen by your application will vary depending on which JDBC driver you are using.

Parameters: resultSet The result set to be wrapped lowerCase Should property names be lower cased?

Throws: NullPointerException if resultSet is null SQLException if the metadata for this result set cannot be introspected

Method Detail

copy

protected void copy(ResultSet resultSet)

Copy the column values for each row in the specified ResultSet into a newly created {@link DynaBean}, and add this bean to the list of {@link DynaBean}s that will later by returned by a call to getRows().

Parameters: resultSet The ResultSet whose data is to be copied

Throws: SQLException if an error is encountered copying the data

createDynaBean

protected DynaBean createDynaBean()

Create and return a new {@link DynaBean} instance to be used for representing a row in the underlying result set.

getRows

public List getRows()

Return a List containing the {@link DynaBean}s that represent the contents of each Row from the ResultSet that was the basis of this {@link RowSetDynaClass} instance. These {@link DynaBean}s are disconnected from the database itself, so there is no problem with modifying the contents of the list, or the values of the properties of these {@link DynaBean}s. However, it is the application's responsibility to persist any such changes back to the database, if it so desires.

Copyright (c) 2001-2004 - Apache Software Foundation