Java反射机制:Constructor!

import org.junit.Test; public class ConstructorTest { @Test @SuppressWarnings("unchecked") public void testConstructor(){ try { Class clazz = Class.forName("cn.vicky.utils.User"); Method method = clazz.getDeclaredMethod("getName"); Constructor<? extends Live> constructor = clazz.getConstructor(String.class); System.out.println(method.invoke(constructor.newInstance("Vicky"))); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SecurityException e) { e.printStackTrace(); } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } catch (InstantiationException e) { e.printStackTrace(); } } } abstract class Live{ String name; public Live(String name) { this.name = name; } public String getName() { return name; } } class User extends Live{ public User(String name) { super(name); } public String getName() { return " ---> " +name; } }

打印:

      ---> Vicky

 

package cn.vicky.service.task; import java.io.Serializable; import java.lang.reflect.Constructor; import java.lang.reflect.Method; import java.util.Map; import java.util.logging.Logger; import cn.vicky.service.command.BaseCommand; import com.sun.sgs.app.AppContext; import com.sun.sgs.app.ManagedReference; import com.sun.sgs.app.Task; public class SolutionCommandTask implements Task, Serializable { private static final long serialVersionUID = 1L; private static final Logger logger = Logger.getLogger(SolutionCommandTask.class.getName()); private String className; private String functionName; private Map mapMessage; private String username; private ManagedReference<Task[]> tasksRef; public SolutionCommandTask(String className, String functionName, Map mapMessage, String username, Task... tasks) { super(); this.className = className; this.functionName = functionName; this.mapMessage = mapMessage; this.username = username; if (tasks.length > 0) this.tasksRef = AppContext.getDataManager().createReference(tasks); } public void run() throws Exception { long time1 = System.currentTimeMillis(); try { Class clazz = Class.forName(className); Constructor<? extends BaseCommand> command; Method method = clazz.getMethod(functionName); // Method method = clazz.getDeclaredMethod(functionName); if (tasksRef == null) { command = clazz.getConstructor(Map.class, String.class); method.invoke(command.newInstance(mapMessage, username)); } else { command = clazz.getConstructor(Map.class, String.class, Task[].class); method.invoke(command.newInstance(mapMessage, username, tasksRef.get())); } } catch (Exception e) { e.printStackTrace(); logger.warning("ReceivedMessageTask --> run --> " + e.getMessage()); } long time2 = System.currentTimeMillis(); System.out.println("SolutionCommandTask run() 耗时 ： " + (time2 - time1)); } }