org.helidb.search
Class SearchMode

java.lang.Object
  org.helidb.search.SearchMode

public class SearchMode
extends Object

This class defines constants for all search modes supported by the different databases. A database or database backend may inherit this class or create new instances of it to define its own search modes.

Since:

1.1

Author:

Karl Gustafsson

In_jar:

helidb-core

Field Summary

static SearchMode	CLOSEST_ABOVE Search for an exact match or the closest key value greater than the search key.
static SearchMode	CLOSEST_BELOW Search for an exact match or the closest key value less than the search key.
static SearchMode	CLOSEST_MATCH Search for the closest match.
static SearchMode	EXACT_MATCH Search for an exact match.

Constructor Summary

SearchMode(String tag)
Create a new search mode.

Method Summary

String

toString()

Methods inherited from class java.lang.Object

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

Field Detail

EXACT_MATCH

public static final SearchMode EXACT_MATCH

Search for an exact match.

CLOSEST_MATCH

public static final SearchMode CLOSEST_MATCH

Search for the closest match. If there are two keys with the same distance from the search key, any of them may be returned.

This search mode requires that the compareTo method used (either from the database keys themselves or from a custom Comparator used for the search) return the distance between two compared objects. This means that Number types such as Integer or Long cannot be compared without a custom Comparator since, even though Number is Comparable, the compareTo methods of Number objects do not return the distance between the compared objects.

CLOSEST_BELOW

public static final SearchMode CLOSEST_BELOW

Search for an exact match or the closest key value less than the search key.

This search mode requires that the compareTo method used (either from the database keys themselves or from a custom Comparator used for the search) return the distance between two compared objects. This means that Number types such as Integer or Long cannot be compared without a custom Comparator since, even though Number is Comparable, the compareTo methods of Number objects do not return the distance between the compared objects.

CLOSEST_ABOVE

public static final SearchMode CLOSEST_ABOVE

Search for an exact match or the closest key value greater than the search key.

This search mode requires that the compareTo method used (either from the database keys themselves or from a custom Comparator used for the search) return the distance between two compared objects. This means that Number types such as Integer or Long cannot be compared without a custom Comparator since, even though Number is Comparable, the compareTo methods of Number objects do not return the distance between the compared objects.

Constructor Detail

SearchMode

public SearchMode(String tag)

Create a new search mode. This should only be done to define a new search mode supported by a database. Database clients should only use predefined search mode constants.

Parameters:

tag - A descriptive tag that is returned from the toString() method.

Method Detail

toString

public String toString()

Overrides:

toString in class Object