第六章：（1）Synchronized 锁的八种情况
作者：互联网
一、情景一
1、代码
class Phone {
public synchronized void sendSMS() throws Exception {
System.out.println("------sendSMS");
}
public synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：标准访问，先打印短信还是邮件？
3、运行结果
------sendSMS ------sendEmail
4、分析
二、情景二
1、代码
class Phone {
public synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：停4秒在短信方法内，先打印短信还是邮件？
3、运行结果
------sendSMS ------sendEmail
4、分析
三、情景三
1、代码
class Phone {
public synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
public void getHello() {
System.out.println("------getHello");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone.getHello();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：新增普通的hello方法，是先打短信还是hello？
3、运行结果
------getHello ------sendSMS
4、分析
四、情景四
1、代码
class Phone {
public synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
public void getHello() {
System.out.println("------getHello");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
Phone phone2 = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone2.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：现在有两部手机，先打印短信还是邮件？
3、运行结果
------sendEmail ------sendSMS
4、分析
五、情景五
1、代码
class Phone {
public static synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public static synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
public void getHello() {
System.out.println("------getHello");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：两个静态同步方法，1部手机，先打印短信还是邮件？
3、运行结果
------sendSMS ------sendEmail
4、分析
六、情景六
1、代码
class Phone {
public static synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public static synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
public void getHello() {
System.out.println("------getHello");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
Phone phone2 = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone2.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：两个静态同步方法，2部手机，先打印短信还是邮件？
3、运行结果
------sendSMS ------sendEmail
4、分析
七、情景七
1、代码
class Phone {
public static synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
public void getHello() {
System.out.println("------getHello");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：1个静态同步方法,1个普通同步方法，1部手机，先打印短信还是邮件？
3、运行结果
------sendEmail ------sendSMS
4、分析
八、情景八
1、代码
class Phone {
public static synchronized void sendSMS() throws Exception {
//停留4秒
TimeUnit.SECONDS.sleep(4);
System.out.println("------sendSMS");
}
public synchronized void sendEmail() throws Exception {
System.out.println("------sendEmail");
}
public void getHello() {
System.out.println("------getHello");
}
}
public class Lock_8 {
public static void main(String[] args) throws InterruptedException {
Phone phone = new Phone();
Phone phone2 = new Phone();
new Thread(() -> {
try {
phone.sendSMS();
} catch (Exception e) {
e.printStackTrace();
}
}, "AA").start();
Thread.sleep(100);
new Thread(() -> {
try {
phone2.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}, "BB").start();
}
}
2、问题：1个静态同步方法,1个普通同步方法，2部手机，先打印短信还是邮件？
3、运行结果
------sendEmail ------sendSMS
4、分析
九、总结
标签：Exception,Synchronized,Phone,sendSMS,八种,------,void,第六章,public 来源： https://www.cnblogs.com/niujifei/p/15833906.html