Java - ThreadGroup getName() 方法

描述

Java ThreadGroup getName() 方法返回該執行緒組的名稱。

宣告

以下是 java.lang.ThreadGroup.getName() 方法的宣告

public final String getName()

引數

無

返回值

此方法返回該執行緒組的名稱。

異常

無

獲取 ThreadGroup 物件名稱示例

以下示例展示了在單個 ThreadGroup 物件的情況下 ThreadGroup getName() 方法的使用。我們建立了一個 ThreadGroup 物件併為其指定了一個名稱。然後，我們使用前面建立的 threadgroup 物件建立了兩個執行緒。使用 getName() 方法，我們獲取了 thread group 物件的名稱。

package com.tutorialspoint;

public class ThreadGroupDemo implements Runnable {
   public static void main(String[] args) {
      ThreadGroupDemo tg = new ThreadGroupDemo();
      tg.start();
   }

   public void start() {
      try {     
         // create a ThreadGroup
         ThreadGroup threadGroup = new ThreadGroup("ThreadGroup");

         // create a thread
         Thread t1 = new Thread(threadGroup, this);
         System.out.println("Starting " + t1.getName() + "...");
         t1.start();
            
         // create another thread
         Thread t2 = new Thread(threadGroup, this);
         System.out.println("Starting " + t2.getName() + "...");
         t2.start();

         // returns the name of thread group
         String name = threadGroup.getName();
         System.out.println("Name of threadGroup = " + name);

         // block until the other threads finish
         t1.join();
         t2.join();        


      } catch (InterruptedException ex) {
         System.out.println(ex.toString());
      }
   }

   // implements run()
   public void run() {

      for(int i = 0; i < 4;i++) {
         i++;
         try {
			Thread.sleep(50);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
      }
      System.out.println(Thread.currentThread().getName() + " finished executing.");
   }
} 

輸出

讓我們編譯並執行上述程式，這將產生以下結果：

Starting Thread-0...
Starting Thread-1...
Name of threadGroup = ThreadGroup
Thread-1 finished executing.
Thread-0 finished executing.

在多個 ThreadGroup 物件中獲取 ThreadGroup 名稱的示例

以下示例展示了在多個 ThreadGroup 物件的情況下 ThreadGroup getName() 方法的使用。我們建立了一個 ThreadGroup 物件併為其指定了一個名稱。接下來，我們建立了一個子 ThreadGroup 物件。然後，我們使用前面建立的 threadgroup 物件建立了兩個執行緒。使用 getName() 方法，我們列印每個 threadgroup 物件的名稱。

package com.tutorialspoint;

public class ThreadGroupDemo implements Runnable {
   public static void main(String[] args) {
      ThreadGroupDemo tg = new ThreadGroupDemo();
      tg.start();
   }

   public void start() {
      try {     
         // create a parent ThreadGroup
         ThreadGroup pThreadGroup = new ThreadGroup("parent ThreadGroup");
		 
         // create a child ThreadGroup for parent ThreadGroup
         ThreadGroup cThreadGroup = new ThreadGroup(pThreadGroup, "child ThreadGroup");

         // create a thread
         Thread t1 = new Thread(pThreadGroup, this);
         System.out.println("Starting " + t1.getName() + "...");
         t1.start();
            
         // create another thread
         Thread t2 = new Thread(cThreadGroup, this);
         System.out.println("Starting " + t2.getName() + "...");
         t2.start();

         // returns the name of thread group
         String name = pThreadGroup.getName();
         System.out.println("Name of pThreadGroup = " + name);

         name = cThreadGroup.getName();
         System.out.println("Name of cThreadGroup = " + name);
         // block until the other threads finish
         t1.join();
         t2.join();

      } catch (InterruptedException ex) {
         System.out.println(ex.toString());
      }
   }

   // implements run()
   public void run() {

      for(int i = 0; i < 4;i++) {
         i++;
         try {
			Thread.sleep(50);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
      }
      System.out.println(Thread.currentThread().getName() + " finished executing.");
   }
} 

輸出

讓我們編譯並執行上述程式，這將產生以下結果：

Starting Thread-0...
Starting Thread-1...
Name of pThreadGroup = parent ThreadGroup
Name of cThreadGroup = child ThreadGroup
Thread-0 finished executing.
Thread-1 finished executing.

在子/孫 ThreadGroup 物件中獲取 ThreadGroup 父物件的示例

以下示例展示了在子 ThreadGroup 物件和孫子 ThreadGroup 物件的情況下 ThreadGroup getName() 方法的使用。我們建立了一個 ThreadGroup 物件併為其指定了一個名稱。接下來，我們建立了一個子 ThreadGroup 物件。然後，我們使用前面建立的子 ThreadGroup 物件和孫子 ThreadGroup 物件建立了兩個執行緒。使用 getName() 方法，我們列印每個 threadgroup 物件的名稱。

package com.tutorialspoint;

public class ThreadGroupDemo implements Runnable {
   public static void main(String[] args) {
      ThreadGroupDemo tg = new ThreadGroupDemo();
      tg.start();
   }

   public void start() {
      try {     
         // create a parent ThreadGroup
         ThreadGroup pThreadGroup = new ThreadGroup("Parent ThreadGroup");
		 
         // create a child ThreadGroup for parent ThreadGroup
         ThreadGroup cThreadGroup = new ThreadGroup(pThreadGroup, "Child ThreadGroup");
		 
         // create a grandchild ThreadGroup for parent ThreadGroup
         ThreadGroup gThreadGroup = new ThreadGroup(cThreadGroup, "GrandChild ThreadGroup");

         // create a thread
         Thread t1 = new Thread(cThreadGroup, this);
         System.out.println("Starting " + t1.getName() + "...");
         t1.start();
            
         // create another thread
         Thread t2 = new Thread(gThreadGroup, this);
         System.out.println("Starting " + t2.getName() + "...");
         t2.start();
            
         // returns the name of thread group
         String name = pThreadGroup.getName();
         System.out.println("Name of pThreadGroup = " + name);

         name = cThreadGroup.getName();
         System.out.println("Name of cThreadGroup = " + name);

         name = gThreadGroup.getName();
         System.out.println("Name of gThreadGroup = " + name);

         // block until the other threads finish
         t1.join();
         t2.join();
      } catch (InterruptedException ex) {
         System.out.println(ex.toString());
      }
   }

   // implements run()
   public void run() {

      for(int i = 0; i < 4;i++) {
         i++;
         try {
			Thread.sleep(50);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
      }
      System.out.println(Thread.currentThread().getName() + " finished executing.");
   }
} 

輸出

讓我們編譯並執行上述程式，這將產生以下結果：

Starting Thread-0...
Starting Thread-1...
Name of pThreadGroup = Parent ThreadGroup
Name of cThreadGroup = Child ThreadGroup
Name of gThreadGroup = GrandChild ThreadGroup
Thread-1 finished executing.
Thread-0 finished executing.