java.lang.Object
- org.opencastproject.assetmanager.api.Value

Direct Known Subclasses:

Value.TypedValue
```
@ParametersAreNonnullByDefault
public abstract class Value
extends Object
```
A property value.
The wrapped type is not exposed as a generic type parameter since Values appear in contexts like lists where this type information cannot be preserved. To access the wrapped type one can choose between two options. If the type is known, use get(ValueType). If the type is not known, safely decompose the value with decompose(Fn, Fn, Fn, Fn, Fn).
The value type is a sum type made up from
Use one of the various mk(..) constructors to create a new Value.
See Also:

Property

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`Value.BooleanType`
`static class`	`Value.BooleanValue`	A value of type `Boolean`.
`static class`	`Value.DateType`
`static class`	`Value.DateValue`	A value of type `Date`.
`static class`	`Value.LongType`
`static class`	`Value.LongValue`	A value of type `Long`.
`static class`	`Value.StringType`
`static class`	`Value.StringValue`	A value of type `String`.
`static class`	`Value.TypedValue<A>`	Helper type to reduce boilerplate code.
`static class`	`Value.UntypedType`
`static class`	`Value.ValueType<A>`	ValueType gives evidence that type `A` is suitable for the creation of a `Value`.
`static class`	`Value.VersionType`
`static class`	`Value.VersionValue`	A value of type `Version`.

Field Summary

Fields
Modifier and Type	Field	Description
`static Value.BooleanType`	`BOOLEAN`
`static Value.DateType`	`DATE`
`static Value.LongType`	`LONG`
`static Value.StringType`	`STRING`
`static Value.UntypedType`	`UNTYPED`
`static Value.VersionType`	`VERSION`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`<A> A`	`decompose(com.entwinemedia.fn.Fn<? super String,? extends A> stringValue, com.entwinemedia.fn.Fn<? super Date,? extends A> dateValue, com.entwinemedia.fn.Fn<? super Long,? extends A> longValue, com.entwinemedia.fn.Fn<? super Boolean,? extends A> booleanValue, com.entwinemedia.fn.Fn<? super Version,? extends A> versionValue)`	Decompose (or pattern match) the value instance.
`static <B> com.entwinemedia.fn.Fn<Object,B>`	`doNotMatch()`	Use as a placeholder that yields an `Prelude.unexhaustiveMatch()` error in value decomposition.
`abstract Object`	`get()`	Get the wrapped value.
`<A> A`	`get(Value.ValueType<A> ev)`	Get the wrapped value in a type safe way.
`Value.ValueType<?>`	`getType()`
`static Value.BooleanValue`	`mk(Boolean value)`	Create a new value of type `Boolean`.
`static Value.LongValue`	`mk(Long value)`	Create a new value of type `Long`.
`static Value.StringValue`	`mk(String value)`	Create a new value of type `String`.
`static Value.DateValue`	`mk(Date value)`	Create a new value of type `Date`.
`static <A> Value.TypedValue<A>`	`mk(Value.ValueType<A> mk, A a)`	Generic constructor.
`static Value.VersionValue`	`mk(Version value)`	Create a new value of type `Version`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

STRING

public static final Value.StringType STRING

DATE

public static final Value.DateType DATE

LONG

public static final Value.LongType LONG

BOOLEAN

public static final Value.BooleanType BOOLEAN

VERSION

public static final Value.VersionType VERSION

UNTYPED

public static final Value.UntypedType UNTYPED

Method Detail

get
```
public abstract Object get()
```
Get the wrapped value.

get
```
public final <A> A get(Value.ValueType<A> ev)
```
Get the wrapped value in a type safe way. Use this method if you are sure about the contained value type. Otherwise consider the use of decompose(Fn, Fn, Fn, Fn, Fn).

Parameters:

ev - Evidence type. The type parameter A of the evidence type must match the type of the wrapped value. Any other value will result in an exception being thrown.

Throws:

RuntimeException - if the passed evidence ev does not match the type of the wrapped value

getType

public final Value.ValueType<?> getType()

decompose

public final <A> A decompose(com.entwinemedia.fn.Fn<? super String,? extends A> stringValue,
                             com.entwinemedia.fn.Fn<? super Date,? extends A> dateValue,
                             com.entwinemedia.fn.Fn<? super Long,? extends A> longValue,
                             com.entwinemedia.fn.Fn<? super Boolean,? extends A> booleanValue,
                             com.entwinemedia.fn.Fn<? super Version,? extends A> versionValue)

Decompose (or pattern match) the value instance. Provide a function to handle each possible type. Use doNotMatch() as a placeholder that yields an Prelude.unexhaustiveMatch() error.

doNotMatch
```
public static <B> com.entwinemedia.fn.Fn<Object,B> doNotMatch()
```
Use as a placeholder that yields an Prelude.unexhaustiveMatch() error in value decomposition.

See Also:

decompose(Fn, Fn, Fn, Fn, Fn)

mk

public static Value.StringValue mk(String value)

Create a new value of type String.

mk

public static Value.DateValue mk(Date value)

Create a new value of type Date.

mk

public static Value.LongValue mk(Long value)

Create a new value of type Long.

mk

public static Value.BooleanValue mk(Boolean value)

Create a new value of type Boolean.

mk

public static Value.VersionValue mk(Version value)

Create a new value of type Version.

mk

public static <A> Value.TypedValue<A> mk(Value.ValueType<A> mk,
                                         A a)

Generic constructor. Creates a value for any existing ValueType.

Class Value