object部类和多线程有什么关系哈

object类型和多线程有什么关系哈?
//有"同步"和"异步"两个版本类型的类:

class Demo {

        private ShareState _state;

        public Demo() {


        }

        public Demo(ShareState state) {

            this._state = state;

        }

        public virtual void DoTheJob() { //异步方法.

            for(int i = 0; i < 50000; i++) {

                //lock(_state)    //记住在这里也要同步(一个任务不一定是一个线程).

                _state.IncreaseState();

            }

        }

        public static Demo Synchronized(Demo demo) {    //同步对象.

            if(!demo.IsSynchronized) return new SynchronizationDemo(demo);

            return demo;

        }


        public virtual bool IsSynchronized {    //异步属性.

            get { return false; }

        }


        private class SynchronizationDemo : Demo {

            private object syncRoot = new object(); //用于同步的对象.

            private Demo d;

            public override bool IsSynchronized {   //同步属性.

                get {

                    return true;

                }

            }


            public override void DoTheJob() {   //同步方法.

                lock(syncRoot) {

                    d.DoTheJob();

                }

            }


            public SynchronizationDemo(Demo d) {

                this.d = d;

            }

        }

    }