文章目录
线程的状态
package multiply.com.test;
public class Run {
public static void main(String[] args) {
try {
MyThread t = new MyThread();
System.out.println(" 1 Main1 method state : " + t.getState());
Thread.sleep(1000);
t.start();
Thread.sleep(1000);
System.out.println(" 2 Main1 method state : " + t.getState());
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
package multiply.com.test;
public class MyThread extends Thread {
public MyThread() {
System.out.println("Constuctor method state : " + Thread.currentThread().getState());
}
@Override
public void run() {
super.run();
System.out.println(" Run1 method state : " + Thread.currentThread().getState());
}
}
Constuctor method state : RUNNABLE
1 Main1 method state : NEW
Run1 method state : RUNNABLE
2 Main1 method state : TERMINATED
线程组
线程对象关联线程组：1级关联
package multiply.com.test;
public class Run {
public static void main(String[] args) {
ThreadA a = new ThreadA();
ThreadB b = new ThreadB();
ThreadGroup group = new ThreadGroup("X process group!");
Thread aThread = new Thread(group, a);
Thread bThread = new Thread(group, b);
aThread.start();
bThread.start();
System.out.println("Active process number : " + group.activeCount());
System.out.println(" process name : " + group.getName());
}
}
package multiply.com.test;
public class ThreadA extends Thread {
@Override
public void run() {
super.run();
try {
while (!Thread.currentThread().isInterrupted()) {
System.out.println("Thread name : " + Thread.currentThread().getName());
Thread.sleep(3000);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
package multiply.com.test;
public class ThreadB extends Thread {
@Override
public void run() {
super.run();
try {
while (!Thread.currentThread().isInterrupted()) {
System.out.println("Thread name : " + Thread.currentThread().getName());
Thread.sleep(3000);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
线程对象关联线程组：多级关联
获取根线程组
线程组里面加线程组
组内的线程批量停止
递归和非递归取得组内对象
传入false就是只取得子组
使线程具有有序性
package multiply.com.test;
public class Run {
public static void main(String[] args) {
Object lock = new Object();
MyThread a = new MyThread(lock, "A", 1);
MyThread b = new MyThread(lock, "B", 2);
MyThread c = new MyThread(lock, "C", 0);
a.start();
b.start();
c.start();
}
}
package multiply.com.test;
public class MyThread extends Thread {
private Object lock;
private String showChar;
private int showNumPosition;
private int printCount = 0;
volatile private static int addNumber = 1;
public MyThread(Object lock, String showChar, int showNumPosition) {
super();
this.lock = lock;
this.showChar = showChar;
this.showNumPosition = showNumPosition;
}
@Override
public void run() {
try {
synchronized (lock) {
while (true) {
if (addNumber % 3 == showNumPosition) {
System.out.println("ThreadName=" + Thread.currentThread().getName()
+ " runCount=" + addNumber + " " + showChar);
lock.notifyAll();
addNumber++;
printCount++;
if (printCount == 3) {
break;
}
} else {
lock.wait();
}
}
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
ThreadName=Thread-0 runCount=1 A
ThreadName=Thread-1 runCount=2 B
ThreadName=Thread-2 runCount=3 C
ThreadName=Thread-0 runCount=4 A
ThreadName=Thread-1 runCount=5 B
ThreadName=Thread-2 runCount=6 C
ThreadName=Thread-0 runCount=7 A
ThreadName=Thread-1 runCount=8 B
ThreadName=Thread-2 runCount=9 C
SimpleDateFormat非线程安全
package multiply.com.test;
import java.text.SimpleDateFormat;
public class Test {
public static void main(String[] args) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String[] dateStringArray = new String[] {
"2000-01-01", "2000-01-02",
"2000-01-03", "2000-01-04", "2000-01-05", "2000-01-06",
"2000-01-07", "2000-01-08", "2000-01-09", "2000-01-10" };
MyThread[] threadArray = new MyThread[10];
for (int i = 0; i < 10; i++) {
threadArray[i] = new MyThread(sdf, dateStringArray[i]);
}
for (int i = 0; i < 10; i++) {
threadArray[i].start();
}
}
}
package multiply.com.test;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MyThread extends Thread {
private SimpleDateFormat sdf;
private String dateString;
public MyThread(SimpleDateFormat sdf, String dateString) {
super();
this.sdf = sdf;
this.dateString = dateString;
}
@Override
public void run() {
try {
Date dateRef = sdf.parse(dateString);
String newDateString = sdf.format(dateRef).toString();
if (!newDateString.equals(dateString)) {
System.out.println("ThreadName=" + this.getName()
+ "报错了，日期字符串：" + dateString + " 转换成的日期为："
+ newDateString);
}
} catch (ParseException e) {
e.printStackTrace();
}
}
}
线程中的异常处理
线程组内异常处理
package multiply.com.test;
public class Run {
public static void main(String[] args) {
MyThreadGroup group = new MyThreadGroup("My Thread Group!");
MyThread[] myThread = new MyThread[10];
for (int i = 0; i < myThread.length; i++) {
myThread[i] = new MyThread(group, "Thread " + (i + 1), "1");
myThread[i].start();
}
MyThread t = new MyThread(group, "Exception Thread ", "AA");
t.start();
}
}
package multiply.com.test;
public class MyThread extends Thread {
private String num;
public MyThread(ThreadGroup group, String name, String num) {
super(group, name);
this.num = num;
}
@Override
public void run() {
super.run();
int numInt = Integer.parseInt(num);
System.out.println(Thread.currentThread().getName() + " " + numInt);
while (!this.isInterrupted()) {
}
}
}
package multiply.com.test;
public class MyThreadGroup extends ThreadGroup {
public MyThreadGroup(String name) {
super(name);
}
@Override
public void uncaughtException(Thread t, Throwable e) {
super.uncaughtException(t, e);
this.interrupt();
}
}
