为什么加锁后多运行几次还是会出现错号的现象？该怎么..... - 黑马程序员技术交流社区

/*7、编写三各类Ticket、SealWindow、TicketSealCenter分别代表票信息、售票窗口、售票中心。
* 售票中心分配一定数量的票，由若干个售票窗口进行出售，利用你所学的线程知识来模拟此售票过程。
*
*
*/
public class Test7 {
public static void main(String[] args) {
Prodrucer p1 = new Prodrucer("北京--上海", 1);
SealWindow s1 = new SealWindow();
Thread t1 = new Thread(p1, "生产者1");
Thread t2 = new Thread(p1, "生产者2");
Thread t3 = new Thread(s1, "售票窗口1");
Thread t4 = new Thread(s1, "售票窗口2");
Thread t5 = new Thread(s1, "售票窗口3");
t1.start();
t2.start();
t3.start();
t4.start();
t5.start();
}
}
class SealWindow implements Runnable {
private TicketSealCenter tt = null;
SealWindow() {
tt = TicketSealCenter.getInstance();
}
@Override
public void run() {
tt.put();
}
}
class Prodrucer implements Runnable {
private TicketSealCenter tt = null;
private Ticket t = null;
Prodrucer(String name, int ID) {
t = Ticket.getInstance();
tt = TicketSealCenter.getInstance();
t.setId(ID);
t.setName(name);
}
@Override
public void run() {
tt.make();
}
}
class TicketSealCenter {
private Ticket t = null;
private boolean flag = false;
private Lock lock = new ReentrantLock();
private Condition m = lock.newCondition();
private Condition p = lock.newCondition();
private TicketSealCenter() {
t = Ticket.getInstance();
}
private static final TicketSealCenter tt = new TicketSealCenter();
public static TicketSealCenter getInstance() {
return tt;
}
public void make() {
lock.lock();
try {
while (true) {
if (flag)
m.await();
System.out.println("生产了一张信息为：" + t.toString() + "的票.");
flag = true;
p.signal();
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
}
public void put() {
lock.lock();
try {
while (true) {
if (!flag)
p.await();
System.out.println("出售了一张:" + t.getName() + "的票,Id为:"
+ t.getId());
flag = false;
m.signal();
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
}
}
class Ticket {
private String name;
private int id = 1;
private static final Ticket ticket = new Ticket("请设置票的名字", 1);
private Ticket(String name, int id) {
this.name = name;
this.id = id;
}
public static Ticket getInstance() {
return ticket;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String toString() {
id++;
return this.getName() + "......" + this.getId();
}
}

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import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/*7、编写三各类Ticket、SealWindow、TicketSealCenter分别代表票信息、售票窗口、售票中心。
* 售票中心分配一定数量的票，由若干个售票窗口进行出售，利用你所学的线程知识来模拟此售票过程。
*
*
*/
public class Test7 {
public static void main(String[] args) {
Prodrucer p1 = new Prodrucer("北京--上海", 0);
SealWindow s1 = new SealWindow();
Thread t1 = new Thread(p1, "生产者1");
Thread t2 = new Thread(p1, "生产者2");
Thread t3 = new Thread(s1, "售票窗口1");
Thread t4 = new Thread(s1, "售票窗口2");
Thread t5 = new Thread(s1, "售票窗口3");
t1.start();
t2.start();
t3.start();
t4.start();
t5.start();
}
}
class SealWindow implements Runnable {
private TicketSealCenter tt = null;
SealWindow() {
tt = TicketSealCenter.getInstance();
}
@Override
public void run() {
//while(true){
tt.put();
//}
}
}
class Prodrucer implements Runnable {
private TicketSealCenter tt = null;
private Ticket t = null;
Prodrucer(String name, int ID) {
t = Ticket.getInstance();
tt = TicketSealCenter.getInstance();
t.setId(ID);
t.setName(name);
}
@Override
public void run() {
//while(true){
tt.make();
//}
}
}
class TicketSealCenter {
private static Ticket t = null;
private boolean flag = false;
private final Lock lock = new ReentrantLock();
private final Condition make = lock.newCondition();
private final Condition put = lock.newCondition();
private TicketSealCenter() {
t = Ticket.getInstance();
}
private static final TicketSealCenter tt = new TicketSealCenter();
public static TicketSealCenter getInstance() {
return tt;
}
public void make() {
lock.lock();
try {
while(true){
if(flag){
make.await();//如果flag为真就让Prodrucer的两个线程等地待
// System.out.println( lock.toString()+"make");开始查lock持有的对象用了
}
else{
System.out.println(Thread.currentThread().getName()+": 生产了一张信息为：" + t.toString() + "的票.");
flag = true;
put.signal();//依次唤醒
}//我想着是加了{}这段代码变成了一个语句。算了，不会解释了
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
}
public void put() {
lock.lock();
try {
while(true){
if (!flag){
put.await();//同上
// System.out.println( lock.toString()+"put");
}
else{
System.out.println(Thread.currentThread().getName()+": 出售了一张:" + t.getName() + "的票,Id为:"
+ t.getId());
flag = false;
make.signal();
}
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
}
}
class Ticket {
private String name;
private int id = 0;
private static final Ticket ticket = new Ticket("请设置票的名字", 1);
private Ticket(String name, int id) {
this.name = name;
this.id = id;
}
public static Ticket getInstance() {
return ticket;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String toString() {
id++;
return this.getName() + "......" + this.getId();
}
}

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