net.sf.hajdbc.balancer

Class LoadBalancer<D>

java.lang.Object

net.sf.hajdbc.balancer.LoadBalancer<D>

Type Parameters:

D - either java.sql.Driver or javax.sql.DataSource

All Implemented Interfaces:

Balancer<D>

public class LoadBalancer<D>
extends java.lang.Object
implements Balancer<D>

Balancer implementation whose next() implementation returns the database with the least load.

Author:

Paul Ferraro

Constructor Summary

Constructors

Constructor and Description
LoadBalancer()

Method Summary

Modifier and Type	Method and Description
boolean	add(Database<D> database) Adds the specified database to this balancer.
void	afterInvocation(Database<D> database) Called after an operation is performed on the specified database retrieved via Balancer.next().
java.util.Set<Database<D>>	all() Returns an unmodifiable collection of databases known to this balancer
void	beforeInvocation(Database<D> database) Called before an operation is performed on the specified database retrieved via Balancer.next().
void	clear() Removes all databases from this balancer.
Database<D>	next() Returns the next database from this balancer
boolean	remove(Database<D> database) Removes the specified database from this balancer.

Methods inherited from class java.lang.Object

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

Constructor Detail

LoadBalancer

public LoadBalancer()

Method Detail

all

public java.util.Set<Database<D>> all()

Description copied from interface: Balancer

Returns an unmodifiable collection of databases known to this balancer

Specified by:

all in interface Balancer<D>

Returns:

a collection of database descriptors

See Also:

Balancer.all()

clear

public void clear()

Description copied from interface: Balancer

Removes all databases from this balancer.

Specified by:

clear in interface Balancer<D>

See Also:

Balancer.clear()

remove

public boolean remove(Database<D> database)

Description copied from interface: Balancer

Removes the specified database from this balancer.

Specified by:

remove in interface Balancer<D>

Parameters:

database - a database descriptor

Returns:

true, if the database was removed successfully, false if it did not exist.

See Also:

Balancer.remove(net.sf.hajdbc.Database)

next

public Database<D> next()

Description copied from interface: Balancer

Returns the next database from this balancer

Specified by:

next in interface Balancer<D>

Returns:

the next database from this balancer

See Also:

Balancer.next()

add

public boolean add(Database<D> database)

Description copied from interface: Balancer

Adds the specified database to this balancer.

Specified by:

add in interface Balancer<D>

Parameters:

database - a database descriptor

Returns:

true, if the database was added successfully, false if already existed.

See Also:

Balancer.add(net.sf.hajdbc.Database)

beforeInvocation

public void beforeInvocation(Database<D> database)

Description copied from interface: Balancer

Called before an operation is performed on the specified database retrieved via Balancer.next().

Specified by:

beforeInvocation in interface Balancer<D>

Parameters:

database - a database descriptor

See Also:

Balancer.beforeInvocation(net.sf.hajdbc.Database)

afterInvocation

public void afterInvocation(Database<D> database)

Description copied from interface: Balancer

Called after an operation is performed on the specified database retrieved via Balancer.next().

Specified by:

afterInvocation in interface Balancer<D>

Parameters:

database - a database descriptor

See Also:

Balancer.afterInvocation(net.sf.hajdbc.Database)