org.skfiy.util.v8

类 DoubleMaxUpdater

java.lang.Object

java.lang.Number

org.skfiy.util.v8.DoubleMaxUpdater

所有已实现的接口:

Serializable

public class DoubleMaxUpdater
extends Number
implements Serializable

One or more variables that together maintain a running double maximum with initial value Double.NEGATIVE_INFINITY. When updates (method update(double)) are contended across threads, the set of variables may grow dynamically to reduce contention. Method max() (or, equivalently, doubleValue()) returns the current maximum across the variables maintaining updates.

This class extends Number, but does not define methods such as equals, hashCode and compareTo because instances are expected to be mutated, and so are not useful as collection keys.

jsr166e note: This class is targeted to be placed in java.util.concurrent.atomic.

从以下版本开始:

1.8

作者:

Doug Lea

另请参阅:

序列化表格

构造器概要

构造器

构造器和说明
DoubleMaxUpdater() Creates a new instance with initial value of Double.NEGATIVE_INFINITY.

方法概要

方法

限定符和类型	方法和说明
double	doubleValue() Equivalent to max().
float	floatValue() Returns the max() as a float after a narrowing primitive conversion.
int	intValue() Returns the max() as an int after a narrowing primitive conversion.
long	longValue() Returns the max() as a long after a narrowing primitive conversion.
double	max() Returns the current maximum.
double	maxThenReset() Equivalent in effect to max() followed by reset().
void	reset() Resets variables maintaining updates to Double.NEGATIVE_INFINITY.
String	toString() Returns the String representation of the max().
void	update(double x) Updates the maximum to be at least the given value.

从类继承的方法 java.lang.Number

byteValue, shortValue

从类继承的方法 java.lang.Object

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

构造器详细资料

DoubleMaxUpdater

public DoubleMaxUpdater()

Creates a new instance with initial value of Double.NEGATIVE_INFINITY.

方法详细资料

update

public void update(double x)

Updates the maximum to be at least the given value.

参数:

x - the value to update

max

public double max()

Returns the current maximum. The returned value is NOT an atomic snapshot; invocation in the absence of concurrent updates returns an accurate result, but concurrent updates that occur while the value is being calculated might not be incorporated.

返回:

the maximum

reset

public void reset()

Resets variables maintaining updates to Double.NEGATIVE_INFINITY. This method may be a useful alternative to creating a new updater, but is only effective if there are no concurrent updates. Because this method is intrinsically racy, it should only be used when it is known that no threads are concurrently updating.

maxThenReset

public double maxThenReset()

Equivalent in effect to max() followed by reset(). This method may apply for example during quiescent points between multithreaded computations. If there are updates concurrent with this method, the returned value is not guaranteed to be the final value occurring before the reset.

返回:

the maximum

toString

public String toString()

Returns the String representation of the max().

覆盖:

toString 在类中 Object

返回:

the String representation of the max()

doubleValue

public double doubleValue()

Equivalent to max().

指定者:

doubleValue 在类中 Number

返回:

the max

longValue

public long longValue()

Returns the max() as a long after a narrowing primitive conversion.

指定者:

longValue 在类中 Number

intValue

public int intValue()

Returns the max() as an int after a narrowing primitive conversion.

指定者:

intValue 在类中 Number

floatValue

public float floatValue()

Returns the max() as a float after a narrowing primitive conversion.

指定者:

floatValue 在类中 Number