这个类里有多少错误？

Java基础：

下面的类里有几处错误？ 不通过工具，你能很快的找出来吗？试一下吧！

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.junit.Test;


public class Test {

	static class Person {
		public void m(Collection<Person> persons) {
			
		}
	}
	
	static class Employee extends Person {
		public void <T> test() {
		}
		
	}
	
	static class Student extends Person {
		public void m2(Collection<Student> students) {
			super.m(students);
		}
		
	}
	

	public void arrayStoreExceptionTest() {
		Person[] persons = new Employee[5];
		persons[0] = new Employee();
		persons[1] = new Student();
	}
	
	
	@Test
	public void arrayStoreTest() {
		Person[] persons = new Person[2];
		persons[0] = new Employee();
		persons[1] = new Student();
	}
	
	public void genericTest() {
		List<Person> personList = new ArrayList<Employee>();
		
	}
	
	
	
	
	
	static class Generic<T> {
		
		static T t;
		
		static void method1(T t) {
			
		}
		void m1(T t){
			
		}
		
	}
}