com.sleepycat.bind.tuple
Class SortedDoubleBinding

java.lang.Object
  com.sleepycat.bind.tuple.TupleBase
      com.sleepycat.bind.tuple.TupleBinding
          com.sleepycat.bind.tuple.SortedDoubleBinding

All Implemented Interfaces:

EntryBinding

public class SortedDoubleBinding
extends TupleBinding

A concrete TupleBinding for a Double primitive wrapper or a double primitive.

This class produces byte array values that by default (without a custom comparator) sort correctly, including sorting of negative values. Therefore, this class should normally be used instead of DoubleBinding which does not by default support sorting of negative values. Please note that:

• The byte array (stored) formats used by DoubleBinding and SortedDoubleBinding are different and incompatible. They are not interchangeable once data has been stored.
• An instance of DoubleBinding, not SortedDoubleBinding, is returned by TupleBinding.getPrimitiveBinding(java.lang.Class) method. Therefore, to use SortedDoubleBinding, TupleBinding.getPrimitiveBinding(java.lang.Class) should not be called.

There are two ways to use this class:

1. When using the com.sleepycat.db package directly, the static methods in this class can be used to convert between primitive values and DatabaseEntry objects.
2. When using the com.sleepycat.collections package, an instance of this class can be used with any stored collection.

Constructor Summary

SortedDoubleBinding()

Method Summary

static void	doubleToEntry(double val, DatabaseEntry entry) Converts a simple double value into an entry buffer.
static double	entryToDouble(DatabaseEntry entry) Converts an entry buffer into a simple double value.
Object	entryToObject(TupleInput input) Constructs a key or data object from a TupleInput entry.
protected TupleOutput	getTupleOutput(Object object) Returns an empty TupleOutput instance that will be used by the tuple binding or key creator.
void	objectToEntry(Object object, TupleOutput output) Converts a key or data object to a tuple entry.

Methods inherited from class com.sleepycat.bind.tuple.TupleBinding

entryToObject, getPrimitiveBinding, objectToEntry

Methods inherited from class com.sleepycat.bind.tuple.TupleBase

entryToInput, getTupleBufferSize, inputToEntry, newOutput, newOutput, outputToEntry, setTupleBufferSize

Methods inherited from class java.lang.Object

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

Constructor Detail

SortedDoubleBinding

public SortedDoubleBinding()

Method Detail

entryToObject

public Object entryToObject(TupleInput input)

Description copied from class: TupleBinding

Constructs a key or data object from a TupleInput entry.

Specified by:

entryToObject in class TupleBinding

Parameters:

input - is the tuple key or data entry.

Returns:

the key or data object constructed from the entry.

objectToEntry

public void objectToEntry(Object object,
                          TupleOutput output)

Description copied from class: TupleBinding

Converts a key or data object to a tuple entry.

Specified by:

objectToEntry in class TupleBinding

Parameters:

object - is the key or data object.

output - is the tuple entry to which the key or data should be written.

getTupleOutput

protected TupleOutput getTupleOutput(Object object)

Description copied from class: TupleBase

Returns an empty TupleOutput instance that will be used by the tuple binding or key creator.

The default implementation of this method creates a new TupleOutput with an initial buffer size that can be changed using the TupleBase.setTupleBufferSize(int) method.

This method may be overridden to return a TupleOutput instance. For example, an instance per thread could be created and returned by this method. If a TupleOutput instance is reused, be sure to call its FastOutputStream.reset() method before each use.

Overrides:

getTupleOutput in class TupleBase

Parameters:

object - is the object to be written to the tuple output, and may be used by subclasses to determine the size of the output buffer.

Returns:

an empty TupleOutput instance.

See Also:

TupleBase.setTupleBufferSize(int)

entryToDouble

public static double entryToDouble(DatabaseEntry entry)

Converts an entry buffer into a simple double value.

Parameters:

entry - is the source entry buffer.

Returns:

the resulting value.

doubleToEntry

public static void doubleToEntry(double val,
                                 DatabaseEntry entry)

Converts a simple double value into an entry buffer.

Parameters:

val - is the source value.

entry - is the destination entry buffer.