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package reflection;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
public class Test07 {
public static void main(String[] args)
throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {
//普通的方式来创建对象
test01();
//反射的方式来创建对象，不关闭安全监测机制
test02();
//反射的方式来创建对象，关闭安全监测机制
test03();
}
public static void test01() {
User user = new User();
long startTime = System.currentTimeMillis();
for (int i = 0; i < 1000000000; i++) {
user.getName();
}
long endTime = System.currentTimeMillis();
System.out.println("普通方式执行10亿次：" + (endTime - startTime) + "ms");
}
//反射的方式来创建对象，不关闭安全监测机制
public static void test02()
throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
User user = new User();
Class c1 = user.getClass();
Method getName = c1.getDeclaredMethod("getName", null);
long startTime = System.currentTimeMillis();
for (int i = 0; i < 1000000000; i++) {
getName.invoke(user, null);
}
long endTime = System.currentTimeMillis();
System.out.println("反射的方式来创建对象，不关闭安全监测机制：" + (endTime - startTime) + "ms");
}
//反射的方式来创建对象，关闭安全监测机制
public static void test03()
throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
User user = new User();
Class c1 = user.getClass();
Method getName = c1.getDeclaredMethod("getName", null);
getName.setAccessible(true);
long startTime = System.currentTimeMillis();
for (int i = 0; i < 1000000000; i++) {
getName.invoke(user, null);
}
long endTime = System.currentTimeMillis();
System.out.println("反射的方式来创建对象，关闭安全监测机制：" + (endTime - startTime) + "ms");
}
}