Task (fxgl 0.3.9 API)

java.lang.Object
- com.almasb.fxgl.ai.btree.Task<E>

Type Parameters:

E - type of the blackboard object that tasks use to read or modify game state

Direct Known Subclasses:

BehaviorTree, BranchTask, Decorator, LeafTask
```
@TaskConstraint
public abstract class Task<E>
extends Object
```
This is the abstract base class of all behavior tree tasks. The Task of a behavior tree has a status, one control and a list of children.

Author:

implicit-invocation, davebaol

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class Task.Status
The enumeration of the values that a task's status can have.

Nested Classes
Modifier and Type	Class and Description
`static class`	`Task.Status` The enumeration of the values that a task's status can have.

Field Summary

Fields
Modifier and Type	Field and Description
`protected Task<E>`	`control` The parent of this task
`protected Task<E>`	`guard` The guard of this task
`protected Task.Status`	`status` The status of this task.
`static TaskCloner`	`TASK_CLONER` The clone strategy (if any) that `cloneTask()` will use.
`protected BehaviorTree<E>`	`tree` The behavior tree this task belongs to.

Constructor Summary

Constructors
Constructor and Description

Task()

Constructors
Constructor and Description
`Task()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`addChild(Task<E> child)` This method will add a child to the list of this task's children
`protected abstract int`	`addChildToTask(Task<E> child)` This method will add a child to the list of this task's children
`void`	`cancel()` Terminates this task and all its running children.
`protected void`	`cancelRunningChildren(int startIndex)` Terminates the running children of this task starting from the specified index up to the end.
`boolean`	`checkGuard(Task<E> control)` Checks the guard of this task.
`abstract void`	`childFail(Task<E> task)` This method will be called when one of the children of this task fails
`abstract void`	`childRunning(Task<E> runningTask, Task<E> reporter)` This method will be called when one of the ancestors of this task needs to run again
`abstract void`	`childSuccess(Task<E> task)` This method will be called when one of the children of this task succeeds
`Task<E>`	`cloneTask()` Clones this task to a new one.
`protected abstract Task<E>`	`copyTo(Task<E> task)` Copies this task to the given task.
`void`	`end()` This method will be called by `success()`, `fail()` or `cancel()`, meaning that this task's status has just been set to `Task.Status.SUCCEEDED`, `Task.Status.FAILED` or `Task.Status.CANCELLED` respectively.
`void`	`fail()` This method will be called in `run()` to inform control that this task has finished running with a failure result
`abstract Task<E>`	`getChild(int i)` Returns the child at the given index.
`abstract int`	`getChildCount()` Returns the number of children of this task.
`Task<E>`	`getGuard()` Returns the guard of this task.
`E`	`getObject()` Returns the blackboard object of the behavior tree this task belongs to.
`Task.Status`	`getStatus()` Returns the status of this task.
`void`	`reset()` Resets this task to make it restart from scratch on next run.
`abstract void`	`run()` This method contains the update logic of this task.
`void`	`running()` This method will be called in `run()` to inform control that this task needs to run again
`void`	`setControl(Task<E> control)` This method will set a task as this task's control (parent)
`void`	`setGuard(Task<E> guard)` Sets the guard of this task.
`void`	`start()` This method will be called once before this task's first run.
`void`	`success()` This method will be called in `run()` to inform control that this task has finished running with a success result

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

- Field Detail
  - TASK_CLONER
```
public static TaskCloner TASK_CLONER
```
    The clone strategy (if any) that cloneTask() will use. Defaults to null, meaning that copyTo(Task) is used instead. In this case, properly overriding this method in each task is developer's responsibility but this gives you the opportunity to target GWT.
    For instance, if you don't care about GWT, you can let Kryo make a deep copy for you like that
```
 
    Task.TASK_CLONER = new TaskCloner() {
       Kryo kryo;
       
        @Override
       public  <T> Task<T> cloneTask (Task<T> task) {
          if (kryo == null) {
             kryo = new Kryo();
             kryo.setInstantiatorStrategy(new DefaultInstantiatorStrategy(new StdInstantiatorStrategy()));
          }
          return kryo.copy(task);
       }
    };
 
 
```
  - status
```
protected Task.Status status
```
    The status of this task.
  - control
```
protected Task<E> control
```
    The parent of this task
  - tree
```
protected BehaviorTree<E> tree
```
    The behavior tree this task belongs to.
  - guard
```
protected Task<E> guard
```
    The guard of this task
- Constructor Detail
  - Task
```
public Task()
```
- Method Detail
  - addChild
```
public final int addChild(Task<E> child)
```
    This method will add a child to the list of this task's children
    
    Parameters:
    
    child - the child task which will be added
    
    Returns:
    
    the index where the child has been added.
    
    Throws:
    
    IllegalStateException - if the child cannot be added for whatever reason.
  - addChildToTask
```
protected abstract int addChildToTask(Task<E> child)
```
    This method will add a child to the list of this task's children
    
    Parameters:
    
    child - the child task which will be added
    
    Returns:
    
    the index where the child has been added.
    
    Throws:
    
    IllegalStateException - if the child cannot be added for whatever reason.
  - getChildCount
```
public abstract int getChildCount()
```
    Returns the number of children of this task.
    
    Returns:
    
    an int giving the number of children of this task
  - getChild
```
public abstract Task<E> getChild(int i)
```
    Returns the child at the given index.
  - getObject
```
public E getObject()
```
    Returns the blackboard object of the behavior tree this task belongs to.
    
    Throws:
    
    IllegalStateException - if this task has never run
  - getGuard
```
public Task<E> getGuard()
```
    Returns the guard of this task.
  - setGuard
```
public void setGuard(Task<E> guard)
```
    Sets the guard of this task.
    
    Parameters:
    
    guard - the guard
  - getStatus
```
public final Task.Status getStatus()
```
    Returns the status of this task.
  - setControl
```
public final void setControl(Task<E> control)
```
    This method will set a task as this task's control (parent)
    
    Parameters:
    
    control - the parent task
  - checkGuard
```
public boolean checkGuard(Task<E> control)
```
    Checks the guard of this task.
    
    Parameters:
    
    control - the parent task
    
    Returns:
    
    true if guard evaluation succeeds or there's no guard; false otherwise.
    
    Throws:
    
    IllegalStateException - if guard evaluation returns any status other than Task.Status.SUCCEEDED and Task.Status.FAILED.
  - start
```
public void start()
```
    This method will be called once before this task's first run.
  - end
```
public void end()
```
    This method will be called by success(), fail() or cancel(), meaning that this task's status has just been set to Task.Status.SUCCEEDED, Task.Status.FAILED or Task.Status.CANCELLED respectively.
  - run
```
public abstract void run()
```
    This method contains the update logic of this task. The actual implementation MUST call running(), success() or fail() exactly once.
  - running
```
public final void running()
```
    This method will be called in run() to inform control that this task needs to run again
  - success
```
public final void success()
```
    This method will be called in run() to inform control that this task has finished running with a success result
  - fail
```
public final void fail()
```
    This method will be called in run() to inform control that this task has finished running with a failure result
  - childSuccess
```
public abstract void childSuccess(Task<E> task)
```
    This method will be called when one of the children of this task succeeds
    
    Parameters:
    
    task - the task that succeeded
  - childFail
```
public abstract void childFail(Task<E> task)
```
    This method will be called when one of the children of this task fails
    
    Parameters:
    
    task - the task that failed
  - childRunning
```
public abstract void childRunning(Task<E> runningTask,
                                  Task<E> reporter)
```
    This method will be called when one of the ancestors of this task needs to run again
    
    Parameters:
    
    runningTask - the task that needs to run again
    
    reporter - the task that reports, usually one of this task's children
  - cancel
```
public final void cancel()
```
    Terminates this task and all its running children. This method MUST be called only if this task is running.
  - cancelRunningChildren
```
protected void cancelRunningChildren(int startIndex)
```
    Terminates the running children of this task starting from the specified index up to the end.
    
    Parameters:
    
    startIndex - the start index
  - reset
```
public void reset()
```
    Resets this task to make it restart from scratch on next run.
  - cloneTask
```
public Task<E> cloneTask()
```
    Clones this task to a new one. If you don't specify a clone strategy through TASK_CLONER the new task is instantiated via reflection and copyTo(Task) is invoked.
    
    Returns:
    
    the cloned task
    
    Throws:
    
    TaskCloneException - if the task cannot be successfully cloned.
  - copyTo
```
protected abstract Task<E> copyTo(Task<E> task)
```
    Copies this task to the given task. This method is invoked by cloneTask() only if TASK_CLONER is null which is its default value.
    
    Parameters:
    
    task - the task to be filled
    
    Returns:
    
    the given task for chaining
    
    Throws:
    
    TaskCloneException - if the task cannot be successfully copied.

Class Task<E>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

TASK_CLONER

status

control

tree

guard

Constructor Detail

Task

Method Detail

addChild

addChildToTask

getChildCount

getChild

getObject

getGuard

setGuard

getStatus

setControl

checkGuard

start

end

run

running

success

fail

childSuccess

childFail

childRunning

cancel

cancelRunningChildren

reset

cloneTask

copyTo