使用Tread创建线程
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| package com.wsx.test;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class ThreadTest {
@Test
public void test1() {
final Logger logger = LoggerFactory.getLogger(ThreadTest.class);
Thread thread = new Thread() {
@Override
public void run() {
logger.debug("running");
}
};
thread.setName("t1");
thread.start();
logger.debug("running");
}
}
|
得到输出
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| 13:23:33.225 [t1] DEBUG com.wsx.test.ThreadTest - running
13:23:33.225 [main] DEBUG com.wsx.test.ThreadTest - running
|
使用Runnable
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| @Test
public void test2(){
final Logger logger = LoggerFactory.getLogger(ThreadTest.class);
Runnable runnable = new Runnable() {
public void run() {
logger.debug("runing");
}
};
Thread thread = new Thread(runnable,"t2");
thread.start();
logger.debug("running");
}
|
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| 13:29:08.503 [t2] DEBUG com.wsx.test.ThreadTest - runing
13:29:08.503 [main] DEBUG com.wsx.test.ThreadTest - running
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lambda表达式
注意到Runnable源码中有注解@FunctionalInterface,那么他就可以被lambda表达式简化，因为只有一个方法
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| @Test
public void test3() {
final Logger logger = LoggerFactory.getLogger(ThreadTest.class);
Runnable runnable = () -> {
logger.debug("runing");
};
Thread thread = new Thread(runnable, "t3");
thread.start();
logger.debug("running");
}
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Thread和Runnable
Thread在用Runnable构造的时候，把他赋值给了一个target变量，然后run
FutureTask和Callable
下面的代码会阻塞
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| @Test
public void test4() throws ExecutionException, InterruptedException {
final Logger logger = LoggerFactory.getLogger(ThreadTest.class);
FutureTask<Integer> task = new FutureTask<>(new Callable<Integer>() {
@Override
public Integer call() throws Exception {
logger.debug("runing...");
Thread.sleep(1000);
return 100;
}
});
Thread thread = new Thread(task, "t2");
thread.start();
logger.debug("running");
logger.debug("{}", task.get());
}
|
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| 13:48:00.930 [main] DEBUG com.wsx.test.ThreadTest - running
13:48:00.930 [t2] DEBUG com.wsx.test.ThreadTest - runing...
13:48:01.937 [main] DEBUG com.wsx.test.ThreadTest - 100
|
jps
可以查看java程序的pid
jstack <pid> 查看某个java进程的所有线程状态,非动态
jconsole可以查看java进程中线程的图形界面
他还可以远程连接，注意需要在运行java程序的时候要加入一些参数，而且注意关闭防火墙
ps
script
, ps 看进程，grep筛选
kill + PID杀死进程
top
他用表格来显示，还是动态的
-H 表示查看线程，-p表示pid
script
