一，JAVA设计四个线程对象，两个线程执行加操作，两个线程执行减操作

package one;import java.io.*;
public class one1 implements Runnable{ private static int count=0;public void run(){while(true){if(Thread.currentThread().getName().startsWith("add"))count++;elsecount--;System.out.print(count);try{Thread.sleep(500);}catch(Exception e){e.printStackTrace();}}}public static void main(String[] args) throws Exception {one1 test=new one1();Thread t1=new Thread(test,"add1");Thread t2=new Thread(test,"add2");Thread t3=new Thread(test,"mul1");Thread t4=new Thread(test,"mul2");t1.start();t2.start();t3.start();t4.start();}
}

二，设计一个生产计算机和搬运计算机的类，要求生产出一台计算机就搬运走一台，如果没有新的计算机生产出来，则搬运工要等待新的计算机产出，如果生产出的计算机没有被搬走，则要等待计算机被搬走后再生产，并统计出生产计算机的数量

 package one;class Computer{private int sum=0;private boolean flag=false;private String name="thinkPad";public synchronized void set(){//synchronized是同步码if(flag){try{super.wait();}catch(Exception e){e.printStackTrace();}}try{Thread.sleep(1000);}catch(Exception e){e.printStackTrace();}sum++;System.out.print("生产了"+sum+"台"+name+"电脑      ");flag=true;super.notify();}public synchronized void get(){if(!flag){try{super.wait();}catch(Exception e){e.printStackTrace();}}try{Thread.sleep(1000);}catch(Exception e){e.printStackTrace();}System.out.print("搬走了一台"+name+"\n");flag=false;super.notify();//解除wait()方法的冻结}}class made implements Runnable{private Computer computer=null;public made(Computer computer){this.computer=computer;}public void run(){for(int i=0;i<10;i++){this.computer.set();}}}class move implements Runnable{private Computer computer=null;public move(Computer computer){this.computer=computer;}public void run(){for(int i=0;i<10;i++){this.computer.get();}}}
public class one1 { public static void main(String[] args) throws Exception {Computer c=new Computer();made m1=new made(c);Thread t1=new Thread(m1);move m2=new move(c);Thread t2=new Thread(m2);t1.start();t2.start();}
}

运行结果：