org.mmbase.storage.search.implementation
Class BasicStep

java.lang.Object
  org.mmbase.storage.search.implementation.BasicStep

All Implemented Interfaces:

Serializable, Step

Direct Known Subclasses:

BasicRelationStep

public class BasicStep
extends Object
implements Step, Serializable

Basic implementation. The step alias is not set on default.

Since:

MMBase-1.7

Version:

$Id: BasicStep.java 41982 2010-04-20 14:05:14Z michiel $

Author:

Rob van Maris

See Also:

Serialized Form

Field Summary

protected String	alias
protected String	builder
protected boolean	modifiable
protected SortedSet<Integer>	nodes Nodenumber set for nodes to be included (ordered using integer comparison).

Constructor Summary

BasicStep(String builder)
Constructor.

Method Summary

Step	addNode(int nodeNumber) Adds node to nodes.
boolean	equals(Object obj) Compares this step to the specified object.
String	getAlias() Gets the alias associated with this step.
SortedSet<Integer>	getNodes() Gets nodenumbers for nodes that must be included in this step.
String	getTableName() Gets the associated builder.
int	hashCode()
BasicStep	setAlias(String alias) Sets alias property.
void	setUnmodifiable()
String	toString() Returns a string representation of this Step.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

builder

protected final String builder

alias

protected String alias

nodes

protected SortedSet<Integer> nodes

Nodenumber set for nodes to be included (ordered using integer comparison).

modifiable

protected boolean modifiable

Constructor Detail

BasicStep

BasicStep(String builder)

Constructor.

Parameters:

builder - The builder.

Throws:

IllegalArgumentException - when an invalid argument is supplied.

Method Detail

setAlias

public BasicStep setAlias(String alias)

Sets alias property.

Parameters:

alias - The alias property.

Returns:

This BasicStep instance.

Throws:

IllegalArgumentException - when an invalid argument is supplied.

addNode

public Step addNode(int nodeNumber)

Adds node to nodes.

Specified by:

addNode in interface Step

Parameters:

nodeNumber - The nodenumber of the node.

Returns:

This BasicStep instance.

Throws:

IllegalArgumentException - when an invalid argument is supplied.

getTableName

public String getTableName()

Gets the associated builder.

Specified by:

getTableName in interface Step

Returns:

The builder.

getAlias

public String getAlias()

Description copied from interface: Step

Gets the alias associated with this step.

This corresponds to a table alias in SQL SELECT-syntax.

Specified by:

getAlias in interface Step

getNodes

public SortedSet<Integer> getNodes()

Description copied from interface: Step

Gets nodenumbers for nodes that must be included in this step. A null value indicates that no such constraint is applied.

This corresponds to a "number IN (....)" constraint in SQL SELECT syntax.

Note that this can also be achieved by using a FieldValueInConstraint on the "number" field.

Specified by:

getNodes in interface Step

equals

public boolean equals(Object obj)

Description copied from interface: Step

Compares this step to the specified object. The result is true if and only if the argument is a non-null Step, but not RelationStep, object associated with the same tablename, using the same alias and including the same nodes.

Specified by:

equals in interface Step

Overrides:

equals in class Object

Parameters:

obj - The object to compare with.

Returns:

true if the objects are equal, false otherwise.

See Also:

RelationStep.equals(java.lang.Object)

hashCode

public int hashCode()

Specified by:

hashCode in interface Step

Overrides:

hashCode in class Object

toString

public String toString()

Description copied from interface: Step

Returns a string representation of this Step. The string representation has the form "Step(tablename:<tablename>, alias:<alias>, nodes:<nodes>)" where

• <tablename> is the tablename returnedby getTableName()
• <alias> is the alias returned by getAlias()
• <nodes> is the string representation of the ordered list of nodenumbers returned by getNodes()

Specified by:

toString in interface Step

Overrides:

toString in class Object

Returns:

A string representation of this Step.

setUnmodifiable

public void setUnmodifiable()

Specified by:

setUnmodifiable in interface Step