本文实例讲述了java基于线程池和反射机制实现定时任务的方法。分享给大家供大家参考,具体如下:
主要包括如下实现类:
1. Main类:
任务执行的入口:
调用main方法,开始加载任务配置并执行任务
package com.yanek.task; import java.util.List; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.TimeUnit; public class Main { /** * @param args */ public static void main(String[] args) { ScheduledExecutorService scheduExec = Executors.newScheduledThreadPool(1); /* TaskModel tm=new TaskModel(); tm.setClassName("com.yanek.task.TaskA"); tm.setMethodName("testA"); tm.setInitialDelay(3); tm.setPeriod(5); */ List tasks=XmlReader.getTasks(); for (int i=0;i
2. MyTask 类 实现Runnable接口,在main类中调用
package com.yanek.task; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.Date; public class MyTask implements Runnable { private TaskModel taskModel; public MyTask() {} public MyTask(TaskModel tm) { this.taskModel = tm; } public void run() { System.out.println("call at " + (new Date())); try { Class<&#63;> classType = Class.forName(taskModel.getClassName()); Method getMethod = classType.getMethod(taskModel.getMethodName()); getMethod.invoke(classType); } catch (SecurityException e) { e.printStackTrace(); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } } }
3. TaskModel: 对任务类的封装
package com.yanek.task; public class TaskModel { public String getClassName() { return className; } public void setClassName(String className) { this.className = className; } public String getMethodName() { return methodName; } public void setMethodName(String methodName) { this.methodName = methodName; } public long getInitialDelay() { return initialDelay; } public void setInitialDelay(long initialDelay) { this.initialDelay = initialDelay; } public long getPeriod() { return period; } public void setPeriod(long period) { this.period = period; } private String className; private String methodName; private long initialDelay; private long period; }
4. XmlReader 任务配置解析类
package com.yanek.task; import java.io.File; import java.io.IOException; import java.util.ArrayList; import java.util.List; import org.apache.commons.lang.StringUtils; import org.jdom.Document; import org.jdom.Element; import org.jdom.JDOMException; import org.jdom.input.SAXBuilder; public class XmlReader { public static void main(String[] args) { XmlReader.getTasks(); } public static List getTasks() { List tasks = new ArrayList(); System.out.println("load task config start..."); String path = "/work/TaskManager/conf/taskconfig.xml"; File file = new File(path); if (file.exists() && !file.isDirectory()) { try { SAXBuilder sx = new SAXBuilder(); Document doc = sx.build(file); Element rootelement = doc.getRootElement(); Listchilds = rootelement.getChildren(); for (int i = 0; i
5. 配置文件:
<&#63;xml version="1.0" encoding="UTF-8"&#63;>com.yanek.task.TaskA testA 5 2 com.yanek.task.TaskB testB 5 3 com.yanek.task.TaskC testC 5 3
6. 测试任务类:
TaskA TaskB TaskC其中定义静态方法 ,这些类的静态方法配置在 xml文件中,被调用。
package com.yanek.task; public class TaskA { /** * @param args */ public static void main(String[] args) { System.out.println("task a test"); } public static void testA() { System.out.println("taska testA method call!"); } } package com.yanek.task; public class TaskB { /** * @param args */ public static void main(String[] args) { System.out.println("task b test"); } public static void testB() { System.out.println("TaskB testB method call!"); } } package com.yanek.task; public class TaskC { /** * @param args */ public static void main(String[] args) { System.out.println("task c test"); } public static void testC() { System.out.println("Taskc testC method call!"); } }
希望本文所述对大家Java程序设计有所帮助。