StateManager (minicp 1.0 API)

All Known Implementing Classes:

Copier, Trailer
```
public interface StateManager
```
The StateManager exposes all the mechanisms and data-structures needed to implement a depth-first-search with reversible states.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`int`	`getLevel()` Returns the current level.
`StateBool`	`makeStateBool(boolean initValue)` Creates a Stateful boolean (restorable)
`StateInt`	`makeStateInt(int initValue)` Creates a Stateful integer (restorable)
`StateMap`	`makeStateMap()` Creates a Stateful map (restorable)
`void`	`onRestore(Procedure listener)` Add a listener that is notified each time the `restoreState()` is called.
`void`	`restoreAllState()` Restores the state as it was at level 0 (first saveState) The level is now -1.
`void`	`restoreState()` Restores state as it was at getLevel()-1 Decrease the level by 1
`void`	`restoreStateUntil(int level)` Restores the state up the the given level.
`void`	`saveState()` Stores the current state such that it can be recovered using restoreState() Increase the level by 1
`void`	`withNewState(Procedure body)` Higher-order function that preserves the state prior to calling body and restores it after.

- Method Detail
  - saveState
```
void saveState()
```
    Stores the current state such that it can be recovered using restoreState() Increase the level by 1
  - restoreState
```
void restoreState()
```
    Restores state as it was at getLevel()-1 Decrease the level by 1
  - restoreAllState
```
void restoreAllState()
```
    Restores the state as it was at level 0 (first saveState) The level is now -1. Notice that you'll probably want to saveState after this operation.
  - restoreStateUntil
```
void restoreStateUntil(int level)
```
    Restores the state up the the given level.
    
    Parameters:
    
    level - the level, a non negative number between 0 and getLevel()
  - onRestore
```
void onRestore(Procedure listener)
```
    Add a listener that is notified each time the restoreState() is called.
    
    Parameters:
    
    listener - the listener to be notified
  - getLevel
```
int getLevel()
```
    Returns the current level. It is increased at each saveState() and decreased at each restoreState(). It is initially equal to -1.
    
    Returns:
    
    the level
  - makeStateInt
```
StateInt makeStateInt(int initValue)
```
    Creates a Stateful integer (restorable)
    
    Parameters:
    
    initValue - the initial setValue
    
    Returns:
    
    a reference to the integer.
  - makeStateBool
```
StateBool makeStateBool(boolean initValue)
```
    Creates a Stateful boolean (restorable)
    
    Parameters:
    
    initValue - the initial setValue
    
    Returns:
    
    a reference to the boolean.
  - makeStateMap
```
StateMap makeStateMap()
```
    Creates a Stateful map (restorable)
    
    Returns:
    
    a reference to the map.
  - withNewState
```
void withNewState(Procedure body)
```
    Higher-order function that preserves the state prior to calling body and restores it after.
    
    Parameters:
    
    body - the first-order function to execute.

Interface StateManager

Method Summary

Method Detail

saveState

restoreState

restoreAllState

restoreStateUntil

onRestore

getLevel

makeStateInt

makeStateBool

makeStateMap

withNewState