Spring MVC 应用程序语法错误

Question

我有这个问题：

Spring MVC application

我用一些新代码解决了问题，制作了 StudentDeleteRepository.java 和 StudentDeleteRepositoryImpl.java 并按照用户的建议添加了标签：

@Autowired
private StudentDeleteRepository studentDeleteRepository;


@Transactional
public Student delete(Student student) {
    return studentDeleteRepository.save(student);
}

StudentDeleteRepository.java 给出错误：

org.springframework.beans.factory.BeanCreationException：创建名为“studentDeleteController”的bean时出错：注入自动装配的依赖项失败；嵌套异常是 org.springframework.beans.factory.BeanCreationException：无法自动装配字段：私有 com.github.elizabetht.service.StudentDeleteService com.github.elizabetht.controller.StudentDeleteController.studentDeleteService；嵌套异常是 org.springframework.beans.factory.BeanCreationException：创建名为“studentDeleteService”的 bean 时出错：注入自动装配的依赖项失败；嵌套异常是 org.springframework.beans.factory.BeanCreationException：无法自动装配字段：私有 com.github.elizabetht.repository.StudentDeleteRepository com.github.elizabetht.service.StudentDeleteServiceImpl.studentDeleteRepository；嵌套异常是 org.springframework.beans.factory.BeanCreationException：创建名为“studentDeleteRepository”的 bean 时出错：FactoryBean 在创建对象时抛出异常；嵌套异常是 java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: 意外令牌：从第 1 行附近的第 10 列 [delete s from com.github.elizabetht.model.Student s where s.userName = :userName 和 s.password = :password]

这里是类StudentDeleteRepositoryImpl.java：

package com.github.elizabetht.repository;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;

import com.github.elizabetht.model.Student;

@Repository("studentDeleteRepository")
public interface StudentDeleteRepository extends JpaRepository<Student, Long> {

    @Query("delete s from Student s where s.userName = :userName and s.password = :password")
    Student deleteByLogin(@Param("userName") String userName, @Param("password") String password);

}

Answer 1

您在代码中使用的查询是 Hibernate 查询，而不是 JPA 查询。 请参阅下面如何在where 条件下编写 JPA 查询。

@Param 注解用于服务声明或实现，而不是在 JPA 存储库实现中。所以相应地改变它。

@Query("delete s from Student s where s.userName = ?1 and s.password = ?2")
Student deleteByLogin(String userName, String password);

Answer 2

delete from Student s where s.userName = ?1 and s.password = ?2