Type Parameters:

T - the type of values that the constraint operates on

All Known Subinterfaces:

IPersister<T>

All Known Implementing Classes:

ComparableConstraint, KindOfQuantity, LinearKindOfQuantity, WrappingPersister
```
public interface IConstraint<T>
```
A constraint on allowed instances of an existing type T, including constrained conversions to and from persistable and interactive strings.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`IConstraint<T>`	`combine(IConstraint<?> other)`	Return a constraint that honors both this constraint and `other`, if such a constraint would accept anything except `null`.
`String`	`interactiveFormat(T value)`	An exact string representation taking locale and internationalization into account.
`T`	`parseInteractive(String interactiveValue)`	Parse an interactive string.
`T`	`parsePersisted(String persistedValue)`	Parse a persisted string.
`String`	`persistableString(T value)`	A string representation independent of locale or internationalization, that when parsed using `parsePersisted(String)` (on this instance) yields a result that is `equal` to the given `value`.
`boolean`	`validate(T value)`	Fundamentally, check that `value` satisfies this constraint and throw an exception otherwise.

- Method Detail
  - combine
```
IConstraint<T> combine(IConstraint<?> other)
```
    Return a constraint that honors both this constraint and other, if such a constraint would accept anything except null. Otherwise, return null.
    
    Returns:
    
    a constraint or null
  - validate
```
boolean validate(T value)
          throws QuantityConversionException
```
    Fundamentally, check that value satisfies this constraint and throw an exception otherwise. As long as the method returns normally, value is a valid value, regardless of the return value. However, when wrapping a persister in a constraint, it is possible that the persister treats some magic values differently. If the constraint isn't aware of these magical values it should typically not try to validate them. This is signaled by the persister by returning true from this method.
    
    Returns:
    
    true if this value is considered magical and further validation should be skipped, false otherwise. Any return value mean that the value is valid.
    
    Throws:
    
    NullPointerException - if value is null and this constraint doesn't allow it
    
    IllegalArgumentException - if some type aspect of value prevents it from being valid
    
    QuantityConversionException - if the constraint isn't satisfied in some other way
  - persistableString
```
String persistableString(T value)
                  throws QuantityConversionException
```
    A string representation independent of locale or internationalization, that when parsed using parsePersisted(String) (on this instance) yields a result that is equal to the given value. That is, the exact representation must be preserved.
    
    Returns:
    
    a string representation independent of locale or internationalization.
    
    Throws:
    
    NullPointerException - if value is null and this constraint doesn't allow it
    
    IllegalArgumentException - if some type aspect of value prevents it from being valid
    
    QuantityConversionException - if the constraint isn't satisfied in some other way
  - parsePersisted
```
T parsePersisted(String persistedValue)
          throws QuantityConversionException
```
    Parse a persisted string. Only guaranteed to be able to parse strings produced by persistableString(Object) on this instance. Only use this on persisted strings, never for interactive input.
    
    Returns:
    
    a valid value for this instance
    
    Throws:
    
    NullPointerException - if persistedValue is null
    
    QuantityConversionException - if persistedValue couldn't be parsed or didn't satisfy the constraint
  - interactiveFormat
```
String interactiveFormat(T value)
                  throws QuantityConversionException
```
    An exact string representation taking locale and internationalization into account. When parsed using parseInteractive(String) (on this instance) yields a result that is equal to the given value. That is, the exact representation must be preserved.
    
    Returns:
    
    a string representation taking locale and internationalization into account.
    
    Throws:
    
    NullPointerException - if value is null and this constraint doesn't allow it
    
    IllegalArgumentException - if some type aspect of value prevents it from being valid
    
    QuantityConversionException - if value doesn't satisfy the constraint
  - parseInteractive
```
T parseInteractive(String interactiveValue)
            throws QuantityConversionException
```
    Parse an interactive string. Only guaranteed to be able to parse strings produced by interactiveFormat(Object) on this instance and in the same locale. Only use this for interactive input, never for persisted strings.
    
    Returns:
    
    a valid value for this instance
    
    Throws:
    
    NullPointerException - if interactiveValue is null
    
    QuantityConversionException - if interactiveValue couldn't be parsed or didn't satisfy the constraint

Interface IConstraint<T>

Method Summary

Method Detail

combine

validate

persistableString

parsePersisted

interactiveFormat

parseInteractive