java - Why can't I initialize an abstract class's method without changing them to static? -

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• non-static variable cannot referenced static context 11 answers

i'm taking tutorial on building simple behavior ai. it's 'brain' class abstract , contains states in "running","success","failure". in ai unit - droid class have method start droid up

public void update(){      if(routine.getstate()==null){         routine.start();     }     routine.act(this, board);  } 

eclipse tells me methods routine not valid because:

cannot make static reference non-static method getstate() type routine

which can getstate have change routinestate static well, can't start or act containt this.

this brain of ai far:

public abstract class routine {      public enum routinestate{         success,         failure,         running     }       public routinestate getstate(){         return state;     }      protected routinestate state;      protected routine() { }      public void start(){         this.state = routinestate.running;     }      public abstract void reset();      public abstract void act(droid droid, board board);      public void succed(){         this.state = routinestate.success;     }      public void fail(){         this.state = routinestate.failure;     }      public boolean issuccess(){         return state.equals(routinestate.success);     }      public boolean isfailure(){         return state.equals(routinestate.failure);     }      public boolean isrunning(){         return state.equals(routinestate.running);     }    } 

if state class field, should static below.

otherwise, you'll need object own state.

public static routinestate getstate(){     return state; }  protected static routinestate state;