1.任意对象锁
public class ThisLockDemo2 {
public static void main(String[] args) {
// TODO Auto-generated method stub
Ticket5 ticket = new Ticket5();
Thread t = new Thread(ticket);
t.start();
try {Thread.sleep(100);} catch (Exception e) {}
ticket.flag = false;
Thread t2 = new Thread(ticket);
t2.start();
}
}
class Ticket5 implements Runnable {
private int tickets = 100;
Object obj = new Object();
boolean flag = true;
@Override
// public synchronized void run() {
public void run() {
if (flag) {
while (true) {
synchronized (obj) { //任意对象锁
if (tickets > 0) {
try {
Thread.sleep(10);
} catch (Exception e) {
}
System.out.println(Thread.currentThread().getName()+"-----"+tickets--);
}
}
}
}else{
while(true){
show();
}
}
}
public synchronized void show() {
if (tickets > 0) {
try {Thread.sleep(10);} catch (Exception e) {}
System.out.println(Thread.currentThread().getName()+"+++++"+tickets--);
}
}
}
输出结果：
Thread-0-----100
Thread-0-----99
Thread-0-----98
Thread-0-----97
Thread-0-----96
Thread-0-----95
Thread-0-----94
Thread-0-----93
Thread-0-----92
Thread-0-----91
Thread-0-----90
Thread-1+++++89
Thread-0-----87
Thread-1+++++88
Thread-1+++++86
Thread-0-----85
Thread-1+++++84
Thread-0-----83
Thread-1+++++82
Thread-0-----81
Thread-1+++++80
Thread-0-----79
Thread-1+++++78
Thread-0-----77
Thread-0-----76
Thread-1+++++76
Thread-1+++++75
Thread-0-----74
Thread-0-----73
Thread-1+++++72
Thread-0-----71
Thread-1+++++70
Thread-1+++++69
Thread-0-----68
Thread-1+++++67
Thread-0-----66
Thread-1+++++65
Thread-0-----64
Thread-1+++++63
Thread-0-----62
Thread-0-----61
Thread-1+++++60
Thread-1+++++59
Thread-0-----58
Thread-1+++++57
Thread-0-----56
Thread-1+++++55
Thread-0-----54
Thread-1+++++53
Thread-0-----52
Thread-0-----51
Thread-1+++++50
Thread-1+++++49
Thread-0-----48
Thread-1+++++47
Thread-0-----46
Thread-0-----45
Thread-1+++++44
Thread-1+++++43
Thread-0-----42
Thread-0-----41
Thread-1+++++40
Thread-0-----38
Thread-1+++++39
Thread-1+++++37
Thread-0-----36
Thread-0-----35
Thread-1+++++34
Thread-1+++++33
Thread-0-----32
Thread-0-----31
Thread-1+++++30
Thread-1+++++29
Thread-0-----28
Thread-1+++++27
Thread-0-----26
Thread-1+++++25
Thread-0-----24
Thread-1+++++23
Thread-0-----22
Thread-1+++++21
Thread-0-----20
Thread-1+++++19
Thread-0-----18
Thread-1+++++17
Thread-0-----16
Thread-1+++++15
Thread-0-----14
Thread-1+++++13
Thread-0-----12
Thread-1+++++11
Thread-0-----10
Thread-1+++++9
Thread-0-----8
Thread-1+++++7
Thread-0-----6
Thread-1+++++5
Thread-0-----4
Thread-1+++++3
Thread-0-----2
Thread-0-----1
Thread-1+++++0
2.同一对象锁：不存在线程安全问题
package day11;
public class ThisLockDemo2 {
public static void main(String[] args) {
// TODO Auto-generated method stub
Ticket5 ticket = new Ticket5();
Thread t = new Thread(ticket);
t.start();
try {Thread.sleep(100);} catch (Exception e) {}
ticket.flag = false;
Thread t2 = new Thread(ticket);
t2.start();
}
}
class Ticket5 implements Runnable {
private int tickets = 100;
Object obj = new Object();
boolean flag = true;
@Override
// public synchronized void run() {
public void run() {
if (flag) {
while (true) {
synchronized (this) {
if (tickets > 0) {
try {
Thread.sleep(10);
} catch (Exception e) {
}
System.out.println(Thread.currentThread().getName()+"-----"+tickets--);
}
}
}
}else{
while(true){
show();
}
}
}
public synchronized void show() { //此方法的对象锁是 this
if (tickets > 0) {
try {Thread.sleep(10);} catch (Exception e) {}
System.out.println(Thread.currentThread().getName()+"+++++"+tickets--);
}
}
}
输出结果：
Thread-0-----100 Thread-0-----99 Thread-0-----98 Thread-0-----97 Thread-0-----96 Thread-0-----95 Thread-0-----94 Thread-0-----93 Thread-0-----92 Thread-0-----91 Thread-0-----90 Thread-0-----89 Thread-0-----88 Thread-0-----87 Thread-0-----86 Thread-0-----85 Thread-0-----84 Thread-0-----83 Thread-0-----82 Thread-0-----81 Thread-0-----80 Thread-0-----79 Thread-0-----78 Thread-0-----77 Thread-0-----76 Thread-0-----75 Thread-0-----74 Thread-0-----73 Thread-0-----72 Thread-0-----71 Thread-0-----70 Thread-0-----69 Thread-0-----68 Thread-0-----67 Thread-0-----66 Thread-1+++++65 Thread-1+++++64 Thread-1+++++63 Thread-1+++++62 Thread-1+++++61 Thread-1+++++60 Thread-1+++++59 Thread-1+++++58 Thread-1+++++57 Thread-1+++++56 Thread-1+++++55 Thread-1+++++54 Thread-1+++++53 Thread-1+++++52 Thread-1+++++51 Thread-1+++++50 Thread-1+++++49 Thread-1+++++48 Thread-1+++++47 Thread-1+++++46 Thread-1+++++45 Thread-1+++++44 Thread-1+++++43 Thread-1+++++42 Thread-1+++++41 Thread-1+++++40 Thread-1+++++39 Thread-1+++++38 Thread-1+++++37 Thread-1+++++36 Thread-1+++++35 Thread-1+++++34 Thread-1+++++33 Thread-1+++++32 Thread-1+++++31 Thread-1+++++30 Thread-1+++++29 Thread-1+++++28 Thread-1+++++27 Thread-1+++++26 Thread-1+++++25 Thread-1+++++24 Thread-1+++++23 Thread-1+++++22 Thread-1+++++21 Thread-1+++++20 Thread-1+++++19 Thread-1+++++18 Thread-1+++++17 Thread-1+++++16 Thread-1+++++15 Thread-1+++++14 Thread-1+++++13 Thread-1+++++12 Thread-1+++++11 Thread-1+++++10 Thread-1+++++9 Thread-1+++++8 Thread-1+++++7 Thread-1+++++6 Thread-1+++++5 Thread-1+++++4 Thread-1+++++3 Thread-1+++++2 Thread-1+++++1