DefaultDynamicValue (Apache Tamaya Injection Support 0.1-incubating API)

java.lang.Object
- org.apache.tamaya.inject.internal.DefaultDynamicValue<T>

Type Parameters:

T - The type of the value.

All Implemented Interfaces:

Serializable, DynamicValue<T>
```
public final class DefaultDynamicValue<T>
extends Object
implements DynamicValue<T>, Serializable
```
A accessor for a single configured value. This can be used to support values that may change during runtime, reconfigured or final. Hereby external code (could be Tamaya configuration listners or client code), can set a new value. Depending on the UpdatePolicy the new value is immedeately active or it requires an active commit by client code. Similarly an instance also can ignore all later changes to the value.
Implementation Details
This class is
- Serializable, when also the item stored is serializable
- Thread safe
See Also:

Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.tamaya.inject.DynamicValue
  DynamicValue.UpdatePolicy

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addListener(PropertyChangeListener l)` Add a listener to be called as weak reference, when this value has been changed.
`void`	`commit()` Commits a new value that has not been committed yet, make it the new value of the instance.
`T`	`commitAndGet()` Performs a commit, if necessary, and returns the current value.
`void`	`discard()` Discards a new value that was published.
`T`	`evaluateValue()` Evaluates the current value dynamically from the underlying configuration.
`T`	`get()` If a value is present in this `DynamicValue`, returns the value, otherwise throws `ConfigException`.
`T`	`getNewValue()` Access a new value that has not yet been committed.
`DynamicValue.UpdatePolicy`	`getUpdatePolicy()` Access the `UpdatePolicy` used for updating this value.
`boolean`	`isPresent()` Return `true` if there is a value present, otherwise `false`.
`static DynamicValue`	`of(Field annotatedField, Configuration configuration)`
`static DynamicValue`	`of(Method method, Configuration configuration)`
`T`	`orElse(T other)` Return the value if present, otherwise return `other`.
`T`	`orElseGet(ConfiguredItemSupplier<? extends T> other)` Return the value if present, otherwise invoke `other` and return the result of that invocation.
`<X extends Throwable> T`	`orElseThrow(ConfiguredItemSupplier<? extends X> exceptionSupplier)` Return the contained value, if present, otherwise throw an exception to be created by the provided supplier.
`void`	`removeListener(PropertyChangeListener l)` Removes a listener to be called, when this value has been changed.
`void`	`setUpdatePolicy(DynamicValue.UpdatePolicy updatePolicy)` Sets a new `UpdatePolicy`.
`boolean`	`updateValue()` Method to check for and apply a new value.

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

- Method Detail
  - of
```
public static DynamicValue of(Field annotatedField,
                              Configuration configuration)
```
  - of
```
public static DynamicValue of(Method method,
                              Configuration configuration)
```
  - commitAndGet
```
public T commitAndGet()
```
    Performs a commit, if necessary, and returns the current value.
    
    Specified by:
    
    commitAndGet in interface DynamicValue<T>
    
    Returns:
    
    the non-null value held by this DynamicValue
    
    Throws:
    
    ConfigException - if there is no value present
    
    See Also:
    
    isPresent()
  - commit
```
public void commit()
```
    Commits a new value that has not been committed yet, make it the new value of the instance. On change any registered listeners will be triggered.
    
    Specified by:
    
    commit in interface DynamicValue<T>
  - discard
```
public void discard()
```
    Discards a new value that was published. No listeners will be informed.
    
    Specified by:
    
    discard in interface DynamicValue<T>
  - getUpdatePolicy
```
public DynamicValue.UpdatePolicy getUpdatePolicy()
```
    Access the UpdatePolicy used for updating this value.
    
    Specified by:
    
    getUpdatePolicy in interface DynamicValue<T>
    
    Returns:
    
    the update policy, never null.
  - setUpdatePolicy
```
public void setUpdatePolicy(DynamicValue.UpdatePolicy updatePolicy)
```
    Sets a new UpdatePolicy.
    
    Specified by:
    
    setUpdatePolicy in interface DynamicValue<T>
    
    Parameters:
    
    updatePolicy - the new policy, not null.
  - addListener
```
public void addListener(PropertyChangeListener l)
```
    Add a listener to be called as weak reference, when this value has been changed.
    
    Specified by:
    
    addListener in interface DynamicValue<T>
    
    Parameters:
    
    l - the listener, not null
  - removeListener
```
public void removeListener(PropertyChangeListener l)
```
    Removes a listener to be called, when this value has been changed.
    
    Specified by:
    
    removeListener in interface DynamicValue<T>
    
    Parameters:
    
    l - the listner to be removed, not null
  - get
```
public T get()
```
    If a value is present in this DynamicValue, returns the value, otherwise throws ConfigException.
    
    Specified by:
    
    get in interface DynamicValue<T>
    
    Returns:
    
    the non-null value held by this Optional
    
    Throws:
    
    ConfigException - if there is no value present
    
    See Also:
    
    isPresent()
  - updateValue
```
public boolean updateValue()
```
    Method to check for and apply a new value. Depending on the UpdatePolicy the value is immediately or deferred visible (or it may even be ignored completely).
    
    Specified by:
    
    updateValue in interface DynamicValue<T>
    
    Returns:
    
    true, if a new value has been detected. The value may not be visible depending on the current DefaultDynamicValue.UpdatePolicy in place.
  - evaluateValue
```
public T evaluateValue()
```
    Evaluates the current value dynamically from the underlying configuration.
    
    Specified by:
    
    evaluateValue in interface DynamicValue<T>
    
    Returns:
    
    the current actual value, or null.
  - getNewValue
```
public T getNewValue()
```
    Access a new value that has not yet been committed.
    
    Specified by:
    
    getNewValue in interface DynamicValue<T>
    
    Returns:
    
    the uncommitted new value, or null.
  - isPresent
```
public boolean isPresent()
```
    Return true if there is a value present, otherwise false.
    
    Specified by:
    
    isPresent in interface DynamicValue<T>
    
    Returns:
    
    true if there is a value present, otherwise false
  - orElse
```
public T orElse(T other)
```
    Return the value if present, otherwise return other.
    
    Specified by:
    
    orElse in interface DynamicValue<T>
    
    Parameters:
    
    other - the value to be returned if there is no value present, may be null
    
    Returns:
    
    the value, if present, otherwise other
  - orElseGet
```
public T orElseGet(ConfiguredItemSupplier<? extends T> other)
```
    Return the value if present, otherwise invoke other and return the result of that invocation.
    
    Specified by:
    
    orElseGet in interface DynamicValue<T>
    
    Parameters:
    
    other - a ConfiguredItemSupplier whose result is returned if no value is present
    
    Returns:
    
    the value if present otherwise the result of other.get()
    
    Throws:
    
    NullPointerException - if value is not present and other is null
  - orElseThrow
```
public <X extends Throwable> T orElseThrow(ConfiguredItemSupplier<? extends X> exceptionSupplier)
                                    throws X extends Throwable
```
    Return the contained value, if present, otherwise throw an exception to be created by the provided supplier.
    NOTE A method reference to the exception constructor with an empty argument list can be used as the supplier. For example, IllegalStateException::new
    
    Specified by:
    
    orElseThrow in interface DynamicValue<T>
    
    Type Parameters:
    
    X - Type of the exception to be thrown
    
    Parameters:
    
    exceptionSupplier - The supplier which will return the exception to be thrown
    
    Returns:
    
    the present value
    
    Throws:
    
    X - if there is no value present
    
    NullPointerException - if no value is present and exceptionSupplier is null
    
    X extends Throwable

Class DefaultDynamicValue<T>

Implementation Details

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.tamaya.inject.DynamicValue

Method Summary

Methods inherited from class java.lang.Object

Method Detail

of

of

commitAndGet

commit

discard

getUpdatePolicy

setUpdatePolicy

addListener

removeListener

get

updateValue

evaluateValue

getNewValue

isPresent

orElse

orElseGet

orElseThrow