ValueExpression (JBoss Log Manager 2.1.19.Final API)

```
public interface ValueExpression<T>
```
Represents a possible value expression. A value is said to be an expression if it matches a ${system.property:DEFAULT_VALUE} pattern.

Author:

James R. Perkins

Nested Class Summary

Nested Classes
Modifier and Type Interface Description

static interface ValueExpression.Resolver<T>
Resolves the value expression from an expression.

Field Summary

Fields
Modifier and Type	Field	Description
`static ValueExpression.Resolver<Boolean>`	`BOOLEAN_RESOLVER`
`static ValueExpression<Boolean>`	`NULL_BOOLEAN_EXPRESSION`
`static ValueExpression<String>`	`NULL_STRING_EXPRESSION`
`static ValueExpression.Resolver<String>`	`STRING_RESOLVER`

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`T`	`getResolvedValue()`	The resolved value.
`String`	`getValue()`	Gets the value of the value which may or may not be an `expression`.
`boolean`	`isExpression()`	Checks whether this is an expression or not.
`String`	`toString()`

- Field Detail
  - NULL_STRING_EXPRESSION
```
static final ValueExpression<String> NULL_STRING_EXPRESSION
```
  - NULL_BOOLEAN_EXPRESSION
```
static final ValueExpression<Boolean> NULL_BOOLEAN_EXPRESSION
```
  - STRING_RESOLVER
```
static final ValueExpression.Resolver<String> STRING_RESOLVER
```
  - BOOLEAN_RESOLVER
```
static final ValueExpression.Resolver<Boolean> BOOLEAN_RESOLVER
```
- Method Detail
  - getResolvedValue
```
T getResolvedValue()
```
    The resolved value.
    If this is an expression the resolved value will be the value from a system property or the default value from the expression if the system property is not set.
    If this is not an expression the value returned will be the non-expression value or null if allowed for the property.
    
    Returns:
    
    the resolved value
  - isExpression
```
boolean isExpression()
```
    Checks whether this is an expression or not.
    
    Returns:
    
    true if this is an expression, otherwise false
  - getValue
```
String getValue()
```
    Gets the value of the value which may or may not be an expression.
    
    Returns:
    
    the value
  - toString
```
String toString()
```
    Overrides:
    
    toString in class Object