org.h2.mvstore.type

类 BasicDataType<T>

java.lang.Object

org.h2.mvstore.type.BasicDataType<T>

所有已实现的接口:

Comparator<T>, DataType<T>

直接已知子类:

ByteArrayDataType, LobStorageMap.BlobMeta.Type, LobStorageMap.BlobReference.Type, LongDataType, MetaType, ObjectDataType, RowDataType, SpatialDataType, StringDataType, ValueDataType, VersionedValueType

public abstract class BasicDataType<T>
extends Object
implements DataType<T>

The base class for data type implementations.

作者:

Andrei Tokar

构造器概要

构造器

构造器和说明
BasicDataType()

方法概要

限定符和类型	方法和说明
int	binarySearch(T key, Object storageObj, int size, int initialGuess) Perform binary search for the key within the storage
protected T[]	cast(Object storage) Cast the storage object to an array of type T.
int	compare(T a, T b) Compare two keys.
boolean	equals(Object obj)
abstract int	getMemory(T obj) Calculates the amount of used memory in bytes.
int	hashCode()
boolean	isMemoryEstimationAllowed() Whether memory estimation based on previously seen values is allowed/desirable
abstract T	read(ByteBuffer buff) Read an object.
void	read(ByteBuffer buff, Object storage, int len) Read a list of objects.
void	write(WriteBuffer buff, Object storage, int len) Write a list of objects.
abstract void	write(WriteBuffer buff, T obj) Write an object.

从类继承的方法 java.lang.Object

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

从接口继承的方法 org.h2.mvstore.type.DataType

createStorage

从接口继承的方法 java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

构造器详细资料

BasicDataType

public BasicDataType()

方法详细资料

getMemory

public abstract int getMemory(T obj)

从接口复制的说明: DataType

Calculates the amount of used memory in bytes.

指定者:

getMemory 在接口中 DataType<T>

参数:

obj - the object

返回:

the used memory

write

public abstract void write(WriteBuffer buff,
                           T obj)

从接口复制的说明: DataType

Write an object.

指定者:

write 在接口中 DataType<T>

参数:

buff - the target buffer

obj - the value

read

public abstract T read(ByteBuffer buff)

从接口复制的说明: DataType

Read an object.

指定者:

read 在接口中 DataType<T>

参数:

buff - the source buffer

返回:

the object

compare

public int compare(T a,
                   T b)

从接口复制的说明: DataType

Compare two keys.

指定者:

compare 在接口中 Comparator<T>

指定者:

compare 在接口中 DataType<T>

参数:

a - the first key

b - the second key

返回:

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

isMemoryEstimationAllowed

public boolean isMemoryEstimationAllowed()

从接口复制的说明: DataType

Whether memory estimation based on previously seen values is allowed/desirable

指定者:

isMemoryEstimationAllowed 在接口中 DataType<T>

返回:

true if memory estimation is allowed

binarySearch

public int binarySearch(T key,
                        Object storageObj,
                        int size,
                        int initialGuess)

从接口复制的说明: DataType

Perform binary search for the key within the storage

指定者:

binarySearch 在接口中 DataType<T>

参数:

key - to search for

storageObj - to search within (an array of type T)

size - number of data items in the storage

initialGuess - for key position

返回:

index of the key , if found, - index of the insertion point, if not

write

public void write(WriteBuffer buff,
                  Object storage,
                  int len)

从接口复制的说明: DataType

Write a list of objects.

指定者:

write 在接口中 DataType<T>

参数:

buff - the target buffer

storage - the objects

len - the number of objects to write

read

public void read(ByteBuffer buff,
                 Object storage,
                 int len)

从接口复制的说明: DataType

Read a list of objects.

指定者:

read 在接口中 DataType<T>

参数:

buff - the target buffer

storage - the objects

len - the number of objects to read

hashCode

public int hashCode()

覆盖:

hashCode 在类中 Object

equals

public boolean equals(Object obj)

指定者:

equals 在接口中 Comparator<T>

覆盖:

equals 在类中 Object

cast

protected final T[] cast(Object storage)

Cast the storage object to an array of type T.

参数:

storage - the storage object

返回:

the array