com.asakusafw.runtime.value

Class ValueOption<V extends ValueOption<V>>

java.lang.Object

com.asakusafw.runtime.value.ValueOption<V>

Type Parameters:

V - self type

All Implemented Interfaces:

WritableRawComparable, Restorable, Comparable<WritableRawComparable>, org.apache.hadoop.io.Writable, org.apache.hadoop.io.WritableComparable<WritableRawComparable>

Direct Known Subclasses:

BooleanOption, ByteOption, DateOption, DateTimeOption, DecimalOption, DoubleOption, FloatOption, IntOption, LongOption, ShortOption, StringOption

public abstract class ValueOption<V extends ValueOption<V>>
extends Object
implements WritableRawComparable, Restorable

Represents nullable and modifiable value. Note that, the sub-classes may be thread unsafe.

Since:

0.1.0

Version:

0.9.1

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	nullValue Whether this value represents null or not.

Constructor Summary

Constructors

Constructor and Description
ValueOption()

Method Summary

Modifier and Type	Method and Description
abstract void	copyFrom(V otherOrNull) Deprecated. Application developer should not use this method directly
boolean	isNull() Returns whether this object represents null or not.
boolean	isPresent() Returns whether this object has any value or not.
void	max(V other) Sets the specified value to this object only if the specified value is greater than this object.
void	min(V other) Sets the specified value to this object only if the specified value is less than this object.
V	orOption(V other) Returns the given value if this represents null.
ValueOption<V>	setNull() Deprecated. Application developer should not use this method directly

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.asakusafw.runtime.io.util.WritableRawComparable

compareInBytes, getSizeInBytes

Methods inherited from interface org.apache.hadoop.io.Writable

readFields, write

Methods inherited from interface java.lang.Comparable

compareTo

Methods inherited from interface com.asakusafw.runtime.value.Restorable

restore

Field Detail

nullValue

protected boolean nullValue

Whether this value represents null or not.

Constructor Detail

ValueOption

public ValueOption()

Method Detail

isNull

public final boolean isNull()

Returns whether this object represents null or not.

Returns:

true if this object represents null, otherwise false

isPresent

public final boolean isPresent()

Returns whether this object has any value or not.

Returns:

true if this object DOES NOT represent null, otherwise false

Since:

0.9.1

setNull

@Deprecated
public final ValueOption<V> setNull()

Deprecated. Application developer should not use this method directly

Makes this value represent null.

Returns:

this

orOption

public final V orOption(V other)

Returns the given value if this represents null.

Parameters:

other - the target value which will be returned if this object represents null

Returns:

the given value if this represents null, otherwise this

Since:

0.9.1

copyFrom

@Deprecated
public abstract void copyFrom(V otherOrNull)

Deprecated. Application developer should not use this method directly

Copies the value from the specified values into this.

Parameters:

otherOrNull - the source object, or null to make this value represent null

min

public final void min(V other)

Sets the specified value to this object only if the specified value is less than this object. However, if either this object or the specified value represents null, this object will also turn to null.

Parameters:

other - the target value

max

public final void max(V other)

Sets the specified value to this object only if the specified value is greater than this object. However, if either this object or the specified value represents null, this object will also turn to null.

Parameters:

other - the target value