正如标题所述，我在Java + Spring / Hibernate项目中遇到了困难，在该项目中，当我要更新和Employee或Customer信息时，它将从数据库的employee_roles / customer_roles表中删除他们的角色。
我在删除用户名时遇到了同样的问题，但是，我可以通过在html页面中为用户名创建隐藏的输入表单来解决此问题。
可以在下面找到运行此项目的文件，如果发现无法在Mac上正常运行，则可能是因为您需要将jdbc.url更改为：jdbc：mysql： // localhost：3306 / spring_pie_deal
https://drive.google.com/file/d/1YAdaGCQXH-tjDy8EfnV0WagcV33I8ADM/view?usp=sharing
员工：
@Entity
@Table(name = "employee")
public class Employee {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
private Long id;
@Column(name = "username")
private String userName;
@Column(name = "password")
private String password;
@Column(name = "first_name")
private String firstName;
@Column(name = "last_name")
private String lastName;
@Column(name = "email")
private String email;
@Column(name = "phone_number")
private String phoneNumber;
@Column(name = "address")
private String address;
@Column(name = "zipcode")
private String zipcode;
@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@JoinTable(name = "employee_roles",
joinColumns = @JoinColumn(name = "employee_id"),
inverseJoinColumns = @JoinColumn(name = "role_id"))
private Collection<Role> roles;
public Employee() {
}
public Employee(String userName, String password, String firstName, String lastName, String email, String phoneNumber, String address, String zipcode) {
this.userName = userName;
this.password = password;
this.firstName = firstName;
this.lastName = lastName;
this.email = email;
this.phoneNumber = phoneNumber;
this.address = address;
this.zipcode = zipcode;
}
public Employee(String userName, String password, String firstName, String lastName, String email, String phoneNumber, String address, String zipcode, Collection<Role> roles) {
this.userName = userName;
this.password = password;
this.firstName = firstName;
this.lastName = lastName;
this.email = email;
this.phoneNumber = phoneNumber;
this.address = address;
this.zipcode = zipcode;
this.roles = roles;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getPhoneNumber() {
return phoneNumber;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getZipcode() {
return zipcode;
}
public void setZipcode(String zipcode) {
this.zipcode = zipcode;
}
public Collection<Role> getRoles() {
return roles;
}
public void setRoles(Collection<Role> roles) {
this.roles = roles;
}
@Override
public String toString() {
return "Employee{" +
"id=" + id +
", userName='" + userName + '\'' +
", password='" + password + '\'' +
", firstName='" + firstName + '\'' +
", lastName='" + lastName + '\'' +
", email='" + email + '\'' +
", phoneNumber='" + phoneNumber + '\'' +
", address='" + address + '\'' +
", zipcode='" + zipcode + '\'' +
", roles=" + roles +
'}';
}
}
角色：
@Entity
@Table(name = "role")
public class Role {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
private Long id;
@Column(name = "name")
private String name;
public Role() {
}
public Role(String name) {
this.name = name;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public String toString() {
return "Role{" + "id=" + id + ", name='" + name + '\'' + '}';
}
}
EmployeeDAOImpl：
@Repository
public class EmployeeDaoImpl implements EmployeeDAO{
@Autowired
private SessionFactory sessionFactory;
// define getEmployee method
@Override
public Employee getEmployee(Long theId) {
// get current hibernate session
Session currentSession = sessionFactory.getCurrentSession();
// get Employee by the id
Employee theEmployee = currentSession.get(Employee.class, theId);
// return the employee
return theEmployee;
}
// define saveEmployee method
@Override
public void saveEmployee(Employee theEmployee) {
// get current hibernate session
Session currentSession = sessionFactory.getCurrentSession();
// save Employee by the id
currentSession.saveOrUpdate(theEmployee);
}
// define deleteEmployee method
@Override
public void deleteEmployee(Long theId) {
// get current hibernate session
Session currentSession = sessionFactory.getCurrentSession();
// delete Employee by id
currentSession.delete(theId);
}
@Override
public List<Employee> getEmployees() {
// get current hibernate session
Session currentSession = sessionFactory.getCurrentSession();
// create query
Query<Employee> theQuery =
currentSession.createQuery("from Employee order by lastName", Employee.class);
// apply result list to variable list
List<Employee> theEmployees = theQuery.getResultList();
// return the result list variable
return theEmployees;
}
@Override
public Employee findByUserName(String userName) {
// get current hibernate session
Session currentSession = sessionFactory.getCurrentSession();
// now create query... where username(from database) matches uName(direct relationship with userName1)
Query<Employee> theQuery = currentSession.createQuery("from Employee where username=:uName", Employee.class);
theQuery.setParameter("uName", userName);
Employee theEmployee = null;
try {
theEmployee = theQuery.getSingleResult();
}
catch (Exception e) {
theEmployee =null;
}
return theEmployee;
}
@Override
public void save(Employee employee) {
// get current hibernate session
Session currentSession = sessionFactory.getCurrentSession();
// create or save user
currentSession.saveOrUpdate(employee);
}
}
Employee-form.jsp：
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<%@ taglib prefix="security" uri="http://www.springframework.org/security/tags" %>
<!DOCTYPE html>
<html>
<head>
<title>Update Employee</title>
<link type="text/css"
rel="stylesheet"
href="${pageContext.request.contextPath}/resources/css/style.css">
<link type="text/css"
rel="stylesheet"
href="${pageContext.request.contextPath}/resources/css/add-customer-style.css">
</head>
<body>
<div id="wrapper">
<div id="header">
<h2>ERM - Employee Relationship Manager</h2>
</div>
</div>
<div id="container">
<h3>Update Employee</h3>
<form:form action="saveEmployee"
modelAttribute="employee">
<!-- need to associate this data with a employee id -->
<form:hidden path="id" />
<table>
<tbody>
<tr>
<td><form:input type="hidden" path="userName" /></td>
</tr>
<tr>
<td><form:input type="hidden" path="password" /></td>
</tr>
<tr>
<td><label>First name:</label></td>
<td><form:input path="firstName" /></td>
</tr>
<tr>
<td><label>Last name:</label></td>
<td><form:input path="lastName" /></td>
</tr>
<tr>
<td><label>Email:</label></td>
<td><form:input path="email" /></td>
</tr>
<tr>
<td><label>Phone Number:</label></td>
<td><form:input path="phoneNumber" /></td>
</tr>
<tr>
<td><label>Address:</label></td>
<td><form:input path="address" /></td>
</tr>
<tr>
<td><label>Zip Code:</label></td>
<td><form:input path="zipcode" /></td>
</tr>
<tr>
<td><label></label></td>
<td><input type="submit" value="Save" class="save" /></td>
</tr>
</tbody>
</table>
</form:form>
<div style="clear; both;"></div>
<!-- Add a logout button -->
<form:form action="${pageContext.request.contextPath}/logout"
method="POST">
<input type="submit" value="Logout" />
</form:form>
<p>
<a href="${pageContext.request.contextPath}/customer/list">Back to List</a>
</p>
</div>
</body>
</html>