EngineController (InterProlog Java Bridge)

java.lang.Object
- com.declarativa.interprolog.EngineController

All Implemented Interfaces:

PrologEngineListener
```
public class EngineController
extends Object
implements PrologEngineListener
```
An auxiliary object which listens to a PrologEngine and depending on its state will enable/disable a bunch of UI Components and/or Actions. It also provides two actions for pause/continue and abort. Two implementations are provided: one assuming use of timed_call, the other of (ctrl-C) breaks.

Author:

mc

Field Summary

Fields
Modifier and Type	Field and Description
`AbstractAction`	`engineStateAction`
`com.declarativa.interprolog.EngineController.PauseContinueAction`	`pauseContinueAction`
`static String`	`STOP_MESSAGE`
`com.declarativa.interprolog.EngineController.AbortAction`	`stopAction`

Constructor Summary

Constructors
Constructor and Description

EngineController(SubprocessEngine pausableEngine, boolean autoHints)

Constructors
Constructor and Description
`EngineController(SubprocessEngine pausableEngine, boolean autoHints)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`availabilityChanged(AbstractPrologEngine source)` In addition to being messaged by the engine, this method also gets called by this controller when entering/leave pause
`void`	`disableWhenBusy(Action item)`
`void`	`disableWhenBusy(Component item)` This component or menu item should be enabled only when the engine is available or paused.
`void`	`disableWhenBusyOrPaused(Action item)`
`void`	`disableWhenBusyOrPaused(Component item)`
`void`	`disableWhenPaused(Component item)`
`boolean`	`isInPause()`
`void`	`javaMessaged(AbstractPrologEngine source)` The Java side is starting processing a javaMessage Prolog goal (callback) request
`static void`	`myMessage(Object target, String method)` For those annoying situations where anonymous classes do not expose their simple methods (void result and no args) elsewhere ;-)
`void`	`queryEnded()` The user query ended
`void`	`queryStarted()` The user has started a query
`void`	`setColorsForFields(Color busyColor, Color idleOrPausedColor, Color needsMoreInputColor)`
`void`	`setHintsForFields(String busyHint, String idleOrPausedHint, String needsMoreInputHint)`
`void`	`setLabelsForState(String busy, String idleOrPaused, String needsMoreInputLabel)`
`void`	`setUItoBusy()`
`void`	`setUItoNeedsMoreInput()`
`void`	`setUItoPausedOrIdle()`
`void`	`stop()`
`String`	`willWork(AbstractPrologEngine source)` Prolog is asking the Java layer permission to continue; return non null (a reason/message) if you want to abort the Prolog computation.

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

- Field Detail
  - engineStateAction
```
public final AbstractAction engineStateAction
```
  - pauseContinueAction
```
public final com.declarativa.interprolog.EngineController.PauseContinueAction pauseContinueAction
```
  - stopAction
```
public final com.declarativa.interprolog.EngineController.AbortAction stopAction
```
  - STOP_MESSAGE
```
public static final String STOP_MESSAGE
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - EngineController
```
public EngineController(SubprocessEngine pausableEngine,
                        boolean autoHints)
```
    Parameters:
    
    pausableEngine - optional; if not null will be sent break requests
    
    autoHints - if true query entry fields will have a hint injected according to engine state
    
    See Also:
    
    com.xsb.xj.util.XJEngineController
- Method Detail
  - queryStarted
```
public void queryStarted()
```
    The user has started a query
  - queryEnded
```
public void queryEnded()
```
    The user query ended
  - willWork
```
public String willWork(AbstractPrologEngine source)
```
    Description copied from interface: PrologEngineListener
    
    Prolog is asking the Java layer permission to continue; return non null (a reason/message) if you want to abort the Prolog computation. During execution of this method you can call Prolog goals, say to introspect system state etc. This requires
    
    Specified by:
    
    willWork in interface PrologEngineListener
    
    Parameters:
    
    source - the Prolog engine that is asking permission
    
    Returns:
    
    null if Prolog can proceed, an error message if it should abort
    
    See Also:
    
    AbstractPrologEngine.setTimedCallIntervall(int)
  - setUItoBusy
```
public void setUItoBusy()
```
  - setUItoPausedOrIdle
```
public void setUItoPausedOrIdle()
```
  - setUItoNeedsMoreInput
```
public void setUItoNeedsMoreInput()
```
  - javaMessaged
```
public void javaMessaged(AbstractPrologEngine source)
```
    Description copied from interface: PrologEngineListener
    
    The Java side is starting processing a javaMessage Prolog goal (callback) request
    
    Specified by:
    
    javaMessaged in interface PrologEngineListener
    
    Parameters:
    
    source - the engine being messaged by Prolog
  - availabilityChanged
```
public void availabilityChanged(AbstractPrologEngine source)
```
    In addition to being messaged by the engine, this method also gets called by this controller when entering/leave pause
    
    Specified by:
    
    availabilityChanged in interface PrologEngineListener
    
    Parameters:
    
    source - an engine
  - disableWhenBusy
```
public void disableWhenBusy(Component item)
```
    This component or menu item should be enabled only when the engine is available or paused. Its window will get a busy cursor when the engine is busy
    
    Parameters:
    
    item - some component
  - disableWhenBusyOrPaused
```
public void disableWhenBusyOrPaused(Component item)
```
  - disableWhenBusyOrPaused
```
public void disableWhenBusyOrPaused(Action item)
```
  - disableWhenPaused
```
public void disableWhenPaused(Component item)
```
  - disableWhenBusy
```
public void disableWhenBusy(Action item)
```
  - setHintsForFields
```
public void setHintsForFields(String busyHint,
                              String idleOrPausedHint,
                              String needsMoreInputHint)
```
  - setColorsForFields
```
public void setColorsForFields(Color busyColor,
                               Color idleOrPausedColor,
                               Color needsMoreInputColor)
```
  - setLabelsForState
```
public void setLabelsForState(String busy,
                              String idleOrPaused,
                              String needsMoreInputLabel)
```
  - myMessage
```
public static void myMessage(Object target,
                             String method)
```
    For those annoying situations where anonymous classes do not expose their simple methods (void result and no args) elsewhere ;-)
    
    Parameters:
    
    target -
    
    method -
  - isInPause
```
public boolean isInPause()
```
  - stop
```
public void stop()
```

Class EngineController

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

engineStateAction

pauseContinueAction

stopAction

STOP_MESSAGE

Constructor Detail

EngineController

Method Detail

queryStarted

queryEnded

willWork

setUItoBusy

setUItoPausedOrIdle

setUItoNeedsMoreInput

javaMessaged

availabilityChanged

disableWhenBusy

disableWhenBusyOrPaused

disableWhenBusyOrPaused

disableWhenPaused

disableWhenBusy

setHintsForFields

setColorsForFields

setLabelsForState

myMessage

isInPause

stop