線程(Thread)類提供了各種方法來處理線程的狀態(tài)。可以使用這些方法來控制線程的執(zhí)行。

下表包含Thread類常用的方法 -

Scala Thread sleep()方法

sleep()方法用于在指定時(shí)間內(nèi)休眠線程，以毫秒為單位作為時(shí)間參數(shù)。

class ThreadExample extends Thread{  
    override def run(){  
    for(i<- 0 to 5){  
            println(i)  
            Thread.sleep(500)  
        }  
    }  

}  

object Demo{  
    def main(args:Array[String]){  
    var t1 = new ThreadExample()  
    var t2 = new ThreadExample()  
        t1.start()  
        t2.start()  
    }  
}

將上面代碼保存到源文件：Demo.scala中，使用以下命令編譯并執(zhí)行代碼 -

D:\software\scala-2.12.3\bin>scalac Demo.scala
D:\software\scala-2.12.3\bin>scala Demo.scal
0
0
1
1
2
2
3
3
4
4
5
5

Scala Thread join()示例

join()方法等待線程死機(jī)，換句話說，join()方法用于保持當(dāng)前正在運(yùn)行的線程的執(zhí)行，直到指定的線程完成它的執(zhí)行。

class ThreadExample extends Thread{  
    override def run(){  
        for(i<- 0 to 5){  
            println(i)  
            Thread.sleep(500)  
        }  
    }  

}  
object MainObject{  
    def main(args:Array[String]){  
        var t1 = new ThreadExample()  
        var t2 = new ThreadExample()  
        var t3 = new ThreadExample()  
        t1.start()  
        t1.join()  
        t2.start()  
        t3.start()  
    }  
}

將上面代碼保存到源文件：Demo.scala中，使用以下命令編譯并執(zhí)行代碼 -

D:\software\scala-2.12.3\bin>scalac Demo.scala
D:\software\scala-2.12.3\bin>scala Demo.scal
0
1
2
3
4
5
0
0
1
1
2
2
3
3
4
4
5
5

Scala setName()方法示例

在以下示例中，正在設(shè)置和獲取線程名稱。

class ThreadExample() extends Thread{  
    override def run(){  
        for(i<- 0 to 5){  
            println(this.getName()+" - "+i)  
            Thread.sleep(500)  
        }  
    }  
}  

object MainObject{  
    def main(args:Array[String]){  
        var t1 = new ThreadExample()  
        var t2 = new ThreadExample()  
        var t3 = new ThreadExample()  
        t1.setName("First Thread")  
        t2.setName("Second Thread")  
        t1.start()  
        t2.start()  
    }  
}

將上面代碼保存到源文件：Demo.scala中，使用以下命令編譯并執(zhí)行代碼 -

D:\software\scala-2.12.3\bin>scalac Demo.scala
D:\software\scala-2.12.3\bin>scala Demo.scal
First Thread - 0
Second Thread - 0
Second Thread - 1
First Thread - 1
Second Thread - 2
First Thread - 2
Second Thread - 3
First Thread - 3
Second Thread - 4
First Thread - 4
Second Thread - 5
First Thread - 5

Scala線程優(yōu)先級(jí)示例

可以使用其預(yù)定義的方法設(shè)置線程優(yōu)先級(jí)，以下示例設(shè)置線程的優(yōu)先級(jí)。

class ThreadExample() extends Thread{  
    override def run(){  
        for(i<- 0 to 5){  
            println(this.getName())  
            println(this.getPriority())  
            Thread.sleep(500)  
        }  
    }  
}  
object Demo{  
    def main(args:Array[String]){  
        var t1 = new ThreadExample()  
        var t2 = new ThreadExample()  
        t1.setName("First Thread")  
        t2.setName("Second Thread")  
        t1.setPriority(Thread.MIN_PRIORITY)  
        t2.setPriority(Thread.MAX_PRIORITY)  
        t1.start()  
        t2.start()  
    }  
}

將上面代碼保存到源文件：Demo.scala中，使用以下命令編譯并執(zhí)行代碼 -

D:\software\scala-2.12.3\bin>scalac Demo.scala
D:\software\scala-2.12.3\bin>scala Demo.scal
First Thread
Second Thread
10
1
Second Thread
10
First Thread
1
Second Thread
10
First Thread
1
Second Thread
10
First Thread
1
Second Thread
10
First Thread
1
Second Thread
10
First Thread
1

Scala線程多任務(wù)示例

以下示例通過使用多個(gè)線程來運(yùn)行多個(gè)任務(wù)，這個(gè)例子說明了如何在Scala中實(shí)現(xiàn)多任務(wù)。

class ThreadExample() extends Thread{  
    override def run(){  
        for(i<- 0 to 5){  
        println(i)              
        Thread.sleep(500)  
    }  
}  
def task(){  
    for(i<- 0 to 5){  
            println(i)  
            Thread.sleep(200)  
        }  
    }  
}  

object Demo{  
    def main(args:Array[String]){  
        var t1 = new ThreadExample()  
        t1.start()  
        t1.task()           
    }  
}

將上面代碼保存到源文件：Demo.scala中，使用以下命令編譯并執(zhí)行代碼 -

D:\software\scala-2.12.3\bin>scalac Demo.scala
D:\software\scala-2.12.3\bin>scala Demo.scal
First Thread
0
0
1
2
1
3
4
2
5
3
4
5