1.方式一：使用synchronize以及wait()、notify() /notifyAll() 的配合使用
package producercomsumer;
/**
* 描述:
*
* @author: fangchangtan
* @version 创建时间：2019年1月7日 下午7:19:26
*/
public class ChangtanTest {
public static void main(String[] args) {
String lock = "lock";
for (int i = 0; i < 3; i++) {
Thread thread1 = new Consumer(lock);
thread1.start();
}
for (int i = 0; i < 3; i++) {
Thread thread2 = new Producer(lock);
thread2.start();
}
}
}
class Consumer extends Thread {
private String lock;
public Consumer(String lock) {
this.lock = lock;
}
public void getValue() {
try {
synchronized (lock) {
if (ValueObject.value == null) {
lock.wait();
}
System.out.println("Consumer:" + ValueObject.value);
ValueObject.value = null;
lock.notifyAll();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public void run() {
while (true) {
getValue();
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
class Producer extends Thread {
private String lock;
public Producer(String lock) {
this.lock = lock;
}
public void setValue() {
try {
synchronized (lock) {
if (ValueObject.value != null) {
lock.wait();
}
ValueObject.value = System.currentTimeMillis() + "";
System.out.println("Producer:" + ValueObject.value);
lock.notifyAll();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public void run() {
while (true) {
setValue();
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
class ValueObject {
public static String value;
}
方式二、使用lock锁、配合await() 、signal() 方式
package producercomsumer;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;
/**
* 描述:
*
* @author: fangchangtan
* @version 创建时间：2019年1月7日 下午7:30:26
*/
public class TankTest {
public static void main(String[] args) {
ReentrantLock lock = new ReentrantLock();
Condition condition = lock.newCondition();
Thread thread1 = new Consumer1(lock, condition);
Thread thread2 = new Producer1(lock, condition);
thread1.start();
thread2.start();
}
}
class Consumer1 extends Thread {
private ReentrantLock lock;
private Condition condition;
public Consumer1(ReentrantLock lock, Condition condition) {
this.lock = lock;
this.condition = condition;
}
public void getValue() {
try {
lock.lock();
if (ValueObject.value == null) {
condition.await();
}
System.out.println("Consumer:" + ValueObject.value);
ValueObject.value = null;
condition.signal();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
lock.unlock();
}
}
@Override
public void run() {
while (true) {
getValue();
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
class Producer1 extends Thread {
private ReentrantLock lock;
private Condition condition;
public Producer1(ReentrantLock lock, Condition condition) {
this.lock = lock;
this.condition = condition;
}
public void setValue() {
try {
lock.lock();
if (ValueObject.value != null) {
condition.await();
}
ValueObject.value = System.currentTimeMillis() + "";
System.out.println("Producer:" + ValueObject.value);
condition.signal();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
lock.unlock();
}
}
@Override
public void run() {
while (true) {
setValue();
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
方式三：使用java自身提供的同步阻塞队列
略…（晚上有示例，自身参考吧）
自身在使用中遇到的问题：
1.类文件MyMain.java.。主函数实现多线程生产和消费
package producercomsumer;
/**
* 描述:
* @author: fangchangtan
* @version 创建时间：2019年1月7日 下午6:57:48
*/
public class MyMain {
private static String lock = "lock";
// private static String value = null;
public static void main(String[] args) {
ProducerX producerX = new ProducerX(lock);
ComsumerX comsumerX = new ComsumerX(lock);
producerX.start();
comsumerX.start();
}
}
class ValueObject {
public static String value;
}
生产者ProducerX ：
package producercomsumer;
import java.util.Random;
/**
* 描述:
*
* @author: fangchangtan
* @version 创建时间：2019年1月7日 下午6:56:16
*/
public class ProducerX extends Thread{
private String lock;
private Random random = new Random();
public ProducerX(String lock) {
this.lock = lock;
}
@Override
public void run() {
while (true) {
try {
synchronized (lock) {
if (ValueObject.value != null) {
lock.wait();
}
ValueObject.value = String.valueOf(random.nextInt(100));
System.out.println("ProducerX: " + ValueObject.value);
lock.notify();
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
消费者ComsumerX：
package producercomsumer;
import com.sun.org.apache.xalan.internal.lib.ExsltBase;
/**
* 描述:
*
* @author: fangchangtan
* @version 创建时间：2019年1月7日 下午6:57:17
*/
public class ComsumerX extends Thread{
private String lock;
public ComsumerX(String lock) {
this.lock = lock;
}
@Override
public void run() {
while (true) {
try {
synchronized (lock) {
if (ValueObject.value == null) {
lock.wait();
}
System.out.println("ComsumerX: " + ValueObject.value);
ValueObject.value = null;
// System.out.println("ComsumerX: " + str);
lock.notify();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
（以上的代码是没问题的，但是自身在之前的实现过程中出现很多异常情况）
自身在使用存在的问题：
1.自身使用字符串变量String value；来存储生产的消息对象，导致的结果是，生产者生产完之后无法唤醒消费者消费数据。是因为，消费者和生产者操作的不是同一个消息容器或者对象，即：String类型的对象是通过值来传递的，因此做不到多线程共享同一个对象，此处后期改为： ValueObject.value来作为消息缓存的容器，可以正常的生产和消费。