專案中把session的管理交給了spring，靠著openEntityManagerInViewFilter逍遙。今天寫junit測試的時候出現了許久未見的no session問題。最後找到了解決方案：
在junit測試類上加上@Transactional標籤，沒錯，就是service層新增的org.springframework.transaction.annotation標籤。然後就再也不報no session的問題了。

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import
 
 org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import
 
 org.springframework.transaction.annotation.Transactional;


@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration(locations = {
        "file:src/main/webapp/WEB-INF/applicationContext.xml",
        "file:src/main/webapp/WEB-INF/spring-mvc.xml",
        "file:src/main/webapp/WEB-INF/context-component.xml"
 
})
public class MessageServiceTest {

    @Autowired
    MessageService service;

    @Test
    @Transactional
    public void findAllTest() {
        Pageable pageable = new PageRequest(0, 10);
        Page<Message> messages = service.findAll(null, pageable);
        for( Message message : messages){
            System.out.println(message.getTopic().getTopicTitle());
        }
    }

}