Java by API/java.lang/ThreadGroup
Содержание
new ThreadGroup(String groupName)
<source lang="java">
/*
* Output:
New thread: Thread[One,5,Group A] New thread: Thread[Two,5,Group A] One: 5 New thread: Thread[Three,5,Group B] New thread: Thread[Four,5,Group B] Here is output from list(): java.lang.ThreadGroup[name=Group A,maxpri=10]
Thread[One,5,Group A] Thread[Two,5,Group A]
java.lang.ThreadGroup[name=Group B,maxpri=10]
Thread[Three,5,Group B] Thread[Four,5,Group B]
Suspending Group A Three: 5 Two: 5 Four: 5 Resuming Group A Four: 4 Three: 4 Waiting for threads to finish. Two: 4
*/
class MyThread extends Thread {
boolean suspended;
MyThread(String threadname, ThreadGroup tgOb) {
super(tgOb, threadname);
System.out.println("New thread: " + this);
suspended = false;
start(); // Start the thread
}
public void run() {
try {
for (int i = 5; i > 0; i--) {
System.out.println(getName() + ": " + i);
Thread.sleep(1000);
synchronized (this) {
while (suspended) {
wait();
}
}
}
} catch (Exception e) {
System.out.println("Exception in " + getName());
}
System.out.println(getName() + " exiting.");
}
void suspendMe() {
suspended = true;
}
synchronized void resumeMe() {
suspended = false;
notify();
}
} public class MainClass {
public static void main(String args[]) {
ThreadGroup groupA = new ThreadGroup("Group A");
ThreadGroup groupB = new ThreadGroup("Group B");
MyThread ob1 = new MyThread("One", groupA);
MyThread ob2 = new MyThread("Two", groupA);
MyThread ob3 = new MyThread("Three", groupB);
MyThread ob4 = new MyThread("Four", groupB);
System.out.println("\nHere is output from list():");
groupA.list();
groupB.list();
System.out.println("Suspending Group A");
Thread tga[] = new Thread[groupA.activeCount()];
groupA.enumerate(tga); // get threads in group
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).suspendMe(); // suspend each thread
}
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
System.out.println("Main thread interrupted.");
}
System.out.println("Resuming Group A");
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).resumeMe();
}
try {
System.out.println("Waiting for threads to finish.");
ob1.join();
ob2.join();
ob3.join();
ob4.join();
} catch (Exception e) {
System.out.println("Exception in Main thread");
}
System.out.println("Main thread exiting.");
}
}
</source>
ThreadGroup: activeCount()
<source lang="java">
/*
* Output:
New thread: Thread[One,5,Group A] New thread: Thread[Two,5,Group A] One: 5 New thread: Thread[Three,5,Group B] New thread: Thread[Four,5,Group B] Here is output from list(): java.lang.ThreadGroup[name=Group A,maxpri=10]
Thread[One,5,Group A] Thread[Two,5,Group A]
java.lang.ThreadGroup[name=Group B,maxpri=10]
Thread[Three,5,Group B] Thread[Four,5,Group B]
Suspending Group A Three: 5 Two: 5 Four: 5 Resuming Group A Four: 4 Three: 4 Waiting for threads to finish. Two: 4
*/
class MyThread extends Thread {
boolean suspended;
MyThread(String threadname, ThreadGroup tgOb) {
super(tgOb, threadname);
System.out.println("New thread: " + this);
suspended = false;
start(); // Start the thread
}
public void run() {
try {
for (int i = 5; i > 0; i--) {
System.out.println(getName() + ": " + i);
Thread.sleep(1000);
synchronized (this) {
while (suspended) {
wait();
}
}
}
} catch (Exception e) {
System.out.println("Exception in " + getName());
}
System.out.println(getName() + " exiting.");
}
void suspendMe() {
suspended = true;
}
synchronized void resumeMe() {
suspended = false;
notify();
}
} public class MainClass {
public static void main(String args[]) {
ThreadGroup groupA = new ThreadGroup("Group A");
ThreadGroup groupB = new ThreadGroup("Group B");
MyThread ob1 = new MyThread("One", groupA);
MyThread ob2 = new MyThread("Two", groupA);
MyThread ob3 = new MyThread("Three", groupB);
MyThread ob4 = new MyThread("Four", groupB);
System.out.println("\nHere is output from list():");
groupA.list();
groupB.list();
System.out.println("Suspending Group A");
Thread tga[] = new Thread[groupA.activeCount()];
groupA.enumerate(tga); // get threads in group
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).suspendMe(); // suspend each thread
}
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
System.out.println("Main thread interrupted.");
}
System.out.println("Resuming Group A");
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).resumeMe();
}
try {
System.out.println("Waiting for threads to finish.");
ob1.join();
ob2.join();
ob3.join();
ob4.join();
} catch (Exception e) {
System.out.println("Exception in Main thread");
}
System.out.println("Main thread exiting.");
}
}
</source>
ThreadGroup: activeGroupCount()
<source lang="java">
public class Main {
public static void main(String[] argv) throws Exception {
ThreadGroup group = Thread.currentThread().getThreadGroup().getParent();
while (group.getParent() != null) {
group = group.getParent();
}
int numThreads = group.activeCount();
Thread[] threads = new Thread[numThreads * 2];
numThreads = group.enumerate(threads, false);
for (int i = 0; i < numThreads; i++) {
Thread thread = threads[i];
System.out.println(thread.getName());
}
int numGroups = group.activeGroupCount();
ThreadGroup[] groups = new ThreadGroup[numGroups * 2];
numGroups = group.enumerate(groups, false);
for (int i = 0; i < numGroups; i++) {
System.out.println(groups[i]);
}
}
}
</source>
ThreadGroup: enumerate(Thread[] thread)
<source lang="java">
/*
* Output:
New thread: Thread[One,5,Group A] New thread: Thread[Two,5,Group A] One: 5 New thread: Thread[Three,5,Group B] New thread: Thread[Four,5,Group B] Here is output from list(): java.lang.ThreadGroup[name=Group A,maxpri=10]
Thread[One,5,Group A] Thread[Two,5,Group A]
java.lang.ThreadGroup[name=Group B,maxpri=10]
Thread[Three,5,Group B] Thread[Four,5,Group B]
Suspending Group A Three: 5 Two: 5 Four: 5 Resuming Group A Four: 4 Three: 4 Waiting for threads to finish. Two: 4
*/
class MyThread extends Thread {
boolean suspended;
MyThread(String threadname, ThreadGroup tgOb) {
super(tgOb, threadname);
System.out.println("New thread: " + this);
suspended = false;
start(); // Start the thread
}
public void run() {
try {
for (int i = 5; i > 0; i--) {
System.out.println(getName() + ": " + i);
Thread.sleep(1000);
synchronized (this) {
while (suspended) {
wait();
}
}
}
} catch (Exception e) {
System.out.println("Exception in " + getName());
}
System.out.println(getName() + " exiting.");
}
void suspendMe() {
suspended = true;
}
synchronized void resumeMe() {
suspended = false;
notify();
}
} public class MainClass {
public static void main(String args[]) {
ThreadGroup groupA = new ThreadGroup("Group A");
ThreadGroup groupB = new ThreadGroup("Group B");
MyThread ob1 = new MyThread("One", groupA);
MyThread ob2 = new MyThread("Two", groupA);
MyThread ob3 = new MyThread("Three", groupB);
MyThread ob4 = new MyThread("Four", groupB);
System.out.println("\nHere is output from list():");
groupA.list();
groupB.list();
System.out.println("Suspending Group A");
Thread tga[] = new Thread[groupA.activeCount()];
groupA.enumerate(tga); // get threads in group
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).suspendMe(); // suspend each thread
}
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
System.out.println("Main thread interrupted.");
}
System.out.println("Resuming Group A");
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).resumeMe();
}
try {
System.out.println("Waiting for threads to finish.");
ob1.join();
ob2.join();
ob3.join();
ob4.join();
} catch (Exception e) {
System.out.println("Exception in Main thread");
}
System.out.println("Main thread exiting.");
}
}
</source>
ThreadGroup: getName()
<source lang="java">
public class Main {
public static void main(String[] args) {
ThreadGroup tg = new ThreadGroup("My ThreadGroup");
MyThread mt = new MyThread(tg, "My Thread");
mt.start();
}
} class MyThread extends Thread {
MyThread(ThreadGroup tg, String name) {
super(tg, name);
}
public void run() {
ThreadGroup tg = getThreadGroup();
System.out.println(tg.getName());
}
}
</source>
ThreadGroup: getParent()
<source lang="java">
public class Main {
public static void main(String[] argv) throws Exception {
ThreadGroup group = Thread.currentThread().getThreadGroup().getParent();
while (group.getParent() != null) {
group = group.getParent();
}
int numThreads = group.activeCount();
Thread[] threads = new Thread[numThreads * 2];
numThreads = group.enumerate(threads, false);
for (int i = 0; i < numThreads; i++) {
Thread thread = threads[i];
System.out.println(thread.getName());
}
int numGroups = group.activeGroupCount();
ThreadGroup[] groups = new ThreadGroup[numGroups * 2];
numGroups = group.enumerate(groups, false);
for (int i = 0; i < numGroups; i++) {
System.out.println(groups[i]);
}
}
}
</source>
ThreadGroup: list()
<source lang="java">
/*
* Output:
New thread: Thread[One,5,Group A] New thread: Thread[Two,5,Group A] One: 5 New thread: Thread[Three,5,Group B] New thread: Thread[Four,5,Group B] Here is output from list(): java.lang.ThreadGroup[name=Group A,maxpri=10]
Thread[One,5,Group A] Thread[Two,5,Group A]
java.lang.ThreadGroup[name=Group B,maxpri=10]
Thread[Three,5,Group B] Thread[Four,5,Group B]
Suspending Group A Three: 5 Two: 5 Four: 5 Resuming Group A Four: 4 Three: 4 Waiting for threads to finish. Two: 4
*/
class MyThread extends Thread {
boolean suspended;
MyThread(String threadname, ThreadGroup tgOb) {
super(tgOb, threadname);
System.out.println("New thread: " + this);
suspended = false;
start(); // Start the thread
}
public void run() {
try {
for (int i = 5; i > 0; i--) {
System.out.println(getName() + ": " + i);
Thread.sleep(1000);
synchronized (this) {
while (suspended) {
wait();
}
}
}
} catch (Exception e) {
System.out.println("Exception in " + getName());
}
System.out.println(getName() + " exiting.");
}
void suspendMe() {
suspended = true;
}
synchronized void resumeMe() {
suspended = false;
notify();
}
} public class MainClass {
public static void main(String args[]) {
ThreadGroup groupA = new ThreadGroup("Group A");
ThreadGroup groupB = new ThreadGroup("Group B");
MyThread ob1 = new MyThread("One", groupA);
MyThread ob2 = new MyThread("Two", groupA);
MyThread ob3 = new MyThread("Three", groupB);
MyThread ob4 = new MyThread("Four", groupB);
System.out.println("\nHere is output from list():");
groupA.list();
groupB.list();
System.out.println("Suspending Group A");
Thread tga[] = new Thread[groupA.activeCount()];
groupA.enumerate(tga); // get threads in group
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).suspendMe(); // suspend each thread
}
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
System.out.println("Main thread interrupted.");
}
System.out.println("Resuming Group A");
for (int i = 0; i < tga.length; i++) {
((MyThread) tga[i]).resumeMe();
}
try {
System.out.println("Waiting for threads to finish.");
ob1.join();
ob2.join();
ob3.join();
ob4.join();
} catch (Exception e) {
System.out.println("Exception in Main thread");
}
System.out.println("Main thread exiting.");
}
}
</source>
