Module com.speedment.runtime.compute

Package com.speedment.runtime.compute

Interface ToStringNullable<T>

Type Parameters:

T - type to extract from

All Superinterfaces:

Comparator<T>, Expression<T>, Function<T,String>, HasCompare<T>, HasCompose<T>, HasHash<T>, ToNullable<T,String,ToString<T>>

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface ToStringNullable<T>
extends Expression<T>, ToNullable<T,String,ToString<T>>, HasHash<T>, HasCompare<T>, HasCompose<T>

Expression that given an entity returns a String value, or null. This expression can be implemented using a lambda, or it can be a result of another operation. It has additional methods for operating on it.

Since:

3.1.0

Author:

Emil Forslund

See Also:

Function

Method Summary

Modifier and Type	Method	Description
String	apply(T object)
default int	compare(T first, T second)
default <V> ToStringNullable<V>	compose(Function<? super V,? extends T> before)	Returns a composed expression that first applies the before function to its input, and then applies this function to the result.
default ExpressionType	expressionType()	Returns the expression type of this expression.
default long	hash(T object)	Hash the specified object into a 64-bit hash.
static <T> ToStringNullable<T>	of(Function<T,String> lambda)	Returns a typed ToStringNullable<T> using the provided lambda.
default ToString<T>	orElse(String value)	Returns an equivalent expression as this, except that it will return the value if given an argument that would cause this expression to return null.
default ToString<T>	orElseGet(ToString<T> getter)	Returns an equivalent expression as this, except that it will return the getter expression if given an argument that would cause this expression to return null.
default ToString<T>	orThrow()	Returns an equivalent expression as this, except that it will throw a NullPointerException if given an argument that would cause this expression to return null.

Methods inherited from interface java.util.Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Methods inherited from interface java.util.function.Function

andThen

Methods inherited from interface com.speedment.runtime.compute.trait.ToNullable

isNotNull, isNotNull, isNull, isNull

Method Detail

of

static <T> ToStringNullable<T> of(Function<T,String> lambda)

Returns a typed ToStringNullable<T> using the provided lambda.

Type Parameters:

T - type to extract from

Parameters:

lambda - to convert

Returns:

a typed ToStringNullable<T> using the provided lambda

Throws:

NullPointerException - if the provided lambda is null

apply

String apply(T object)

Specified by:

apply in interface Function<T,String>

expressionType

default ExpressionType expressionType()

Description copied from interface: Expression

Returns the expression type of this expression. It should be safe to cast this instance into the corresponding interface.

Specified by:

expressionType in interface Expression<T>

Returns:

the expression type

orThrow

default ToString<T> orThrow()

Description copied from interface: ToNullable

Returns an equivalent expression as this, except that it will throw a NullPointerException if given an argument that would cause this expression to return null.

Specified by:

orThrow in interface ToNullable<T,String,ToString<T>>

Returns:

the expression if present

orElseGet

default ToString<T> orElseGet(ToString<T> getter)

Description copied from interface: ToNullable

Returns an equivalent expression as this, except that it will return the getter expression if given an argument that would cause this expression to return null.

Specified by:

orElseGet in interface ToNullable<T,String,ToString<T>>

Parameters:

getter - to apply if null

Returns:

the expression if present, otherwise return getter

orElse

default ToString<T> orElse(String value)

Description copied from interface: ToNullable

Returns an equivalent expression as this, except that it will return the value if given an argument that would cause this expression to return null.

Specified by:

orElse in interface ToNullable<T,String,ToString<T>>

Parameters:

value - value to use if null

Returns:

the expression if present, otherwise return value

hash

default long hash(T object)

Description copied from interface: HasHash

Hash the specified object into a 64-bit hash. If two equal objects are hashed, they must always result in the same hash. However, objects that are not equal may also result in the same hash.

Specified by:

hash in interface HasHash<T>

Parameters:

object - the object to hash

Returns:

the 64-bit hashcode

compare

default int compare(T first,
                    T second)

Specified by:

compare in interface Comparator<T>

Specified by:

compare in interface HasCompare<T>

compose

default <V> ToStringNullable<V> compose(Function<? super V,? extends T> before)

Description copied from interface: HasCompose

Returns a composed expression that first applies the before function to its input, and then applies this function to the result. If evaluation of either function throws an exception, it is relayed to the caller of the composed function.

Specified by:

compose in interface Function<T,String>

Specified by:

compose in interface HasCompose<T>

Type Parameters:

V - the type of input to the before function, and to the composed expression

Parameters:

before - the function to apply before this function is applied

Returns:

a composed function that first applies the before function and then applies this function