如何使用条件或 spring jpa 进行搜索

Question

我正在 mvc spring 中执行搜索功能。我想同时搜索名字和姓氏。如果我在搜索框中输入一个字符串并按回车键，我将在 firstName 中进行搜索，如果在 lastName 中找不到它执行搜索，反之亦然。这意味着我想输入一个字符串并搜索所有字段。这是我的节目内容。

员工：

@Entity
public class Employee implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    private String firstName;
    private String lastName;
    private int age;
    private double salary;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    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 int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }
}

存储库：

@Repository
public interface EmployeeDAO extends  JpaRepository<Employee,Integer>{
    List<Employee> findEmployeeByFirstNameOrLastName(String searchName);

}

控制器：

@RequestMapping(value = "/search")
    public ModelAndView searchByFirstName(@RequestParam String searchName) {
        ModelAndView view = new ModelAndView("showEmployee");
        return view;
    }

查看：

 <div class="row">
        <form method="get" action="/search">
            <div class="small-3 columns">
                <input type="text" id ="txt" name="searchName" >
            </div>

            <div class="small-5 columns end">
                <button id="button-id" type="submit">Search</button>
            </div>
        </form>
    </div>

我已经运行，但它不能同时搜索 firstName 或 LastName。两个如何用一个参数同时搜索 firstName 或 lastName

Answer 1

您需要提供两个字段：

List<Employee> findEmployeeByFirstNameOrLastName(String firstName, String lastName);

然后调用它：

findEmployeeByFirstNameOrLastName("searchName", "searchName");

获取Employee，其firstName或lastName等于"searchName"

最终代码如下：

@Repository
public interface EmployeeDAO extends  JpaRepository<Employee,Integer>{
    List<Employee> findEmployeeByFirstNameOrLastName(String firstName, String lastName);

}


@RequestMapping(value = "/search")
public ModelAndView searchByFirstName(@RequestParam String searchName) {
    ModelAndView view = new ModelAndView("showEmployee");
    // Access employeeDAO here, or use employeeService if you using service
    List<Employee> employees = employeeDao.findEmployeeByFirstNameOrLastName(searchName, searchName);
    view.addObject("employees", employees);
    return view;
}

对于更复杂的情况，您可能希望查看 JPA Criteria API 或 QueryDsl 来创建条件组合，而不是像上面那样提供两个字段 firstName、lastName

Answer 2

Spring Data 的派生查询很有用，但简单地指定查询通常更简单明了：

@Repository
public interface EmployeeDAO extends  JpaRepository<Employee,Integer>{

    @Query("select e from Employee e where e.firstName = :searchName 
               or e.lastName = :searchName)
    List<Employee> findEmployeeByFirstNameOrLastName(
             @Param("searchName") String searchName);

}