ConfigResolver

```
public interface ConfigResolver
```
Implement this interface and provide an instance to ConfigResolveOptions.appendResolver() to provide custom behavior when unresolved substitutions are encountered during resolution.

Since:

1.3.2

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`ConfigValue`	`lookup(java.lang.String path)`	Returns the value to substitute for the given unresolved path.
`ConfigResolver`	`withFallback(ConfigResolver fallback)`	Returns a new resolver that falls back to the given resolver if this one doesn't provide a substitution itself.

- Method Detail
  - lookup
```
lookup(java.lang.String path)
```
    Returns the value to substitute for the given unresolved path. To get the components of the path use ConfigUtil.splitPath(String). If a non-null value is returned that value will be substituted, otherwise resolution will continue to consider the substitution as still unresolved.
    
    Parameters:
    
    path - the unresolved path
    
    Returns:
    
    the value to use as a substitution or null
  - withFallback
```
withFallback(ConfigResolver fallback)
```
    Returns a new resolver that falls back to the given resolver if this one doesn't provide a substitution itself. It's important to handle the case where you already have the fallback with a "return this", i.e. this method should not create a new object if the fallback is the same one you already have. The same fallback may be added repeatedly.
    
    Parameters:
    
    fallback - the previous includer for chaining
    
    Returns:
    
    a new resolver