/** * 状态模式。 * author Bright Lee */ public class StatePattern { public static void main(String[] args) { Context context new Context(); context.request(); context.request(); } } class Context { private State stateA; private State stateB; private State currentState; public Context() { this.stateA new ConcreteStateA(this); this.stateB new ConcreteStateB(this); this.currentState stateA; } public void request() { currentState.handle(); } public State getStateA() { return stateA; } public State getStateB() { return stateB; } void setCurrentState(State currentState) { this.currentState currentState; } } interface State { void handle(); } class ConcreteStateA implements State { private Context context; public ConcreteStateA(Context context) { this.context context; } public void handle() { System.out.println(现在是状态A马上转换到状态B。); context.setCurrentState(context.getStateB()); } } class ConcreteStateB implements State { private Context context; public ConcreteStateB(Context context) { this.context context; } public void handle() { System.out.println(现在是状态B马上转换到状态A。); context.setCurrentState(context.getStateA()); } }运行结果现在是状态A马上转换到状态B。现在是状态B马上转换到状态A。青蛙客服系统https://download.csdn.net/download/look4liming/93326820