org.springframework.batch.sample.common

Class ColumnRangePartitioner

java.lang.Object

org.springframework.batch.sample.common.ColumnRangePartitioner

All Implemented Interfaces:

Partitioner

public class ColumnRangePartitioner
extends java.lang.Object
implements Partitioner

Simple minded partitioner for a range of values of a column in a database table. Works best if the values are uniformly distributed (e.g. auto-generated primary key values).

Author:

Dave Syer

Constructor Summary

Constructors

Constructor and Description
ColumnRangePartitioner()

Method Summary

Modifier and Type	Method and Description
java.util.Map<java.lang.String,ExecutionContext>	partition(int gridSize) Partition a database table assuming that the data in the column specified are uniformly distributed.
void	setColumn(java.lang.String column) The name of the column to partition.
void	setDataSource(javax.sql.DataSource dataSource) The data source for connecting to the database.
void	setTable(java.lang.String table) The name of the SQL table the data are in.

Methods inherited from class java.lang.Object

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

Constructor Detail

ColumnRangePartitioner

public ColumnRangePartitioner()

Method Detail

setTable

public void setTable(java.lang.String table)

The name of the SQL table the data are in.

Parameters:

table - the name of the table

setColumn

public void setColumn(java.lang.String column)

The name of the column to partition.

Parameters:

column - the column name.

setDataSource

public void setDataSource(javax.sql.DataSource dataSource)

The data source for connecting to the database.

Parameters:

dataSource - a DataSource

partition

public java.util.Map<java.lang.String,ExecutionContext> partition(int gridSize)

Partition a database table assuming that the data in the column specified are uniformly distributed. The execution context values will have keys minValue and maxValue specifying the range of values to consider in each partition.

Specified by:

partition in interface Partitioner

Parameters:

gridSize - the size of the map to return

Returns:

a map from identifier to input parameters

See Also:

Partitioner.partition(int)