org.h2.mvstore.rtree

Class SpatialDataType

java.lang.Object

org.h2.mvstore.rtree.SpatialDataType

All Implemented Interfaces:

DataType

public class SpatialDataType
extends java.lang.Object
implements DataType

A spatial data type. This class supports up to 31 dimensions. Each dimension can have a minimum and a maximum value of type float. For each dimension, the maximum value is only stored when it is not the same as the minimum.

Constructor Summary

Constructors

Constructor and Description
SpatialDataType(int dimensions)

Method Summary

Modifier and Type	Method and Description
int	compare(java.lang.Object a, java.lang.Object b) Compare two keys.
boolean	contains(java.lang.Object objA, java.lang.Object objB) Check whether a contains b.
boolean	equals(java.lang.Object a, java.lang.Object b) Check whether two spatial values are equal.
float	getAreaIncrease(java.lang.Object objA, java.lang.Object objB) Get the area increase by extending a to contain b.
int[]	getExtremes(java.util.ArrayList<java.lang.Object> list) Get the most extreme pair (elements that are as far apart as possible).
int	getMemory(java.lang.Object obj) Estimate the used memory in bytes.
void	increaseBounds(java.lang.Object bounds, java.lang.Object add) Increase the bounds in the given spatial object.
boolean	isInside(java.lang.Object objA, java.lang.Object objB) Check whether a is completely inside b and does not touch the given bound.
boolean	isOverlap(java.lang.Object objA, java.lang.Object objB) Check whether the two objects overlap.
java.lang.Object	read(java.nio.ByteBuffer buff) Read an object.
void	read(java.nio.ByteBuffer buff, java.lang.Object[] obj, int len, boolean key) Read a list of objects.
void	write(WriteBuffer buff, java.lang.Object obj) Write an object.
void	write(WriteBuffer buff, java.lang.Object[] obj, int len, boolean key) Write a list of objects.

Methods inherited from class java.lang.Object

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

Constructor Detail

SpatialDataType

public SpatialDataType(int dimensions)

Method Detail

compare

public int compare(java.lang.Object a,
                   java.lang.Object b)

Description copied from interface: DataType

Compare two keys.

Specified by:

compare in interface DataType

Parameters:

a - the first key

b - the second key

Returns:

-1 if the first key is smaller, 1 if larger, and 0 if equal

equals

public boolean equals(java.lang.Object a,
                      java.lang.Object b)

Check whether two spatial values are equal.

Parameters:

a - the first value

b - the second value

Returns:

true if they are equal

getMemory

public int getMemory(java.lang.Object obj)

Description copied from interface: DataType

Estimate the used memory in bytes.

Specified by:

getMemory in interface DataType

Parameters:

obj - the object

Returns:

the used memory

read

public void read(java.nio.ByteBuffer buff,
                 java.lang.Object[] obj,
                 int len,
                 boolean key)

Description copied from interface: DataType

Read a list of objects.

Specified by:

read in interface DataType

Parameters:

buff - the target buffer

obj - the objects

len - the number of objects to read

key - whether the objects are keys

write

public void write(WriteBuffer buff,
                  java.lang.Object[] obj,
                  int len,
                  boolean key)

Description copied from interface: DataType

Write a list of objects.

Specified by:

write in interface DataType

Parameters:

buff - the target buffer

obj - the objects

len - the number of objects to write

key - whether the objects are keys

write

public void write(WriteBuffer buff,
                  java.lang.Object obj)

Description copied from interface: DataType

Write an object.

Specified by:

write in interface DataType

Parameters:

buff - the target buffer

obj - the value

read

public java.lang.Object read(java.nio.ByteBuffer buff)

Description copied from interface: DataType

Read an object.

Specified by:

read in interface DataType

Parameters:

buff - the source buffer

Returns:

the object

isOverlap

public boolean isOverlap(java.lang.Object objA,
                         java.lang.Object objB)

Check whether the two objects overlap.

Parameters:

objA - the first object

objB - the second object

Returns:

true if they overlap

increaseBounds

public void increaseBounds(java.lang.Object bounds,
                           java.lang.Object add)

Increase the bounds in the given spatial object.

Parameters:

bounds - the bounds (may be modified)

add - the value

getAreaIncrease

public float getAreaIncrease(java.lang.Object objA,
                             java.lang.Object objB)

Get the area increase by extending a to contain b.

Parameters:

objA - the bounding box

objB - the object

Returns:

the area

contains

public boolean contains(java.lang.Object objA,
                        java.lang.Object objB)

Check whether a contains b.

Parameters:

objA - the bounding box

objB - the object

Returns:

the area

isInside

public boolean isInside(java.lang.Object objA,
                        java.lang.Object objB)

Check whether a is completely inside b and does not touch the given bound.

Parameters:

objA - the object to check

objB - the bounds

Returns:

true if a is completely inside b

getExtremes

public int[] getExtremes(java.util.ArrayList<java.lang.Object> list)

Get the most extreme pair (elements that are as far apart as possible). This method is used to split a page (linear split). If no extreme objects could be found, this method returns null.

Parameters:

list - the objects

Returns:

the indexes of the extremes