FilterWatcher (OpenNMS 29.0.8 API)

All Known Implementing Classes:

DefaultFilterWatcher
```
public interface FilterWatcher
```
Evaluates filter rule and issues callback when the results change.

Nested Class Summary

Nested Classes
Modifier and Type Interface Description

static interface FilterWatcher.FilterResults

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Closeable`	`watch(String filterRule, java.util.function.Consumer<FilterWatcher.FilterResults> callback)`	Issues callbacks to the given consumer when the results of the filter change.

- Method Detail
  - watch
```
Closeable watch(String filterRule,
                java.util.function.Consumer<FilterWatcher.FilterResults> callback)
```
    Issues callbacks to the given consumer when the results of the filter change. A callback is expected to be issued immediately when the watch session is started. Additional callback will be made if/when the results change.
    
    Parameters:
    
    filterRule - a valid filter rule if null, or empty the filter will match everything
    
    callback - used for callbacks
    
    Returns:
    
    close when done watching