ExistsCallback

java.lang.Object
- com.redwood.scheduler.api.model.ExistsCallback

All Implemented Interfaces:

APIResultSetCallback
```
public class ExistsCallback
extends Object
implements APIResultSetCallback
```
APIResultSetCallback implementation for checking whether or not a query has a result.

Field Summary
- Fields inherited from interface com.redwood.scheduler.api.model.APIResultSetCallback
  NULL

Constructor Summary

Constructors
Constructor Description

ExistsCallback()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`callback(ResultSet rs, ObjectGetter objectGetter)`	Invoked for each result, provided that the previous invocation returned `true`.
`boolean`	`exists()`
`void`	`start()`	Invoked before processing any results.

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

Methods inherited from interface com.redwood.scheduler.api.model.APIResultSetCallback
finish

- Constructor Detail
  - ExistsCallback
```
public ExistsCallback()
```
- Method Detail
  - start
```
public void start()
```
    Description copied from interface: APIResultSetCallback
    
    Invoked before processing any results.
    This is before any calls to APIResultSetCallback.callback(ResultSet, ObjectGetter) are made.
    Note that this may be invoked more than once under some circumstances. (Such circumstances include when the query is restarted due to underlying database errors.)
    
    Specified by:
    
    start in interface APIResultSetCallback
  - callback
```
public boolean callback(ResultSet rs,
                        ObjectGetter objectGetter)
                 throws SQLException
```
    Description copied from interface: APIResultSetCallback
    
    Invoked for each result, provided that the previous invocation returned true.
    
    Specified by:
    
    callback in interface APIResultSetCallback
    
    Parameters:
    
    rs - the result-set to process
    
    objectGetter - an object-getter with can be used to convert the result-set into one (or more) objects.
    
    Returns:
    
    true if this method should be invoked for the next result, false if subsequent results are to be discarded.
    
    Throws:
    
    SQLException - Exception thrown when a database-related error occurs
  - exists
```
public boolean exists()
```