2014-01-26 49 views
2

答复ajax请求时存在一些小问题。最初,我有最简单的宁静服务,基于春季启动MVCSpring mvc restful - 错误的json回复格式

模型:

import javax.persistence.*; 
import java.util.*; 

@Entity 
@Table(name = "testmodel") 
public class TestModel 
{ 
    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY)//Postgresql sequence generator 
    private long id; 

    @Column(name = "name") 
    private String name; 

    @Column(name = "content") 
    private String content; 


    //Constructor 
    public TestModel() 
    { 
    } 

    //Id getter 
    public long getId() 
    { 
     return this.id; 
    } 

    //Name getter-setter 
    public String getName() 
    { 
     return this.name; 
    } 

    public void setName(String name) 
    { 
     this.name = name; 
    } 

    //Content getter-setter 
    public String getContent() 
    { 
     return this.content; 
    } 

    public void setContent(String content) 
    { 
     this.content = content; 
    } 
} 

DAO为模型:

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

import java.util.*; 

public interface TetsModelDAO extends JpaRepository<Samples, Long> 
{ 
    @Query("SELECT s FROM TestModel s WHERE LOWER(s.name) LIKE LOWER(:entry) ORDER BY s.name") 
    List<TestModel> fetchByNameEntry(@Param("entry") String entry); 
} 

控制器:

import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.web.bind.annotation.RequestMapping; 
import org.springframework.web.bind.annotation.RequestParam; 
import org.springframework.web.bind.annotation.RestController; 
import java.util.List; 

@RestController 
@RequestMapping("/") 
public class TestController 
{ 
    @Autowired 
    private TetsModelDAO testmodel; 

    @RequestMapping("/name") 
    public List<TestModel> getDatasetsByNameEntry(@RequestParam("entry") String entry) 
    { 
     return testmodel.fetchByNameEntry("%"+entry+"%"); 
    } 
} 

客户端AJAX请求:

$.ajax(
{ 
    url : "/name?entry=", //get all records 
    method: "GET" 
}) 

这个例子完美的作品 - 字符串化的回复看起来像非标准JSON结构:

{"id":"1", "name":"John", "content":"blablabla1"} 
{"id":"2", "name":"Sam", "content":"blablabla2"} 
{"id":"3", "name":"Ken", "content":"blablabla3"} 

然而,当我试图定义JPQL查询的Fileds明确(读取,也就是说,只有ID领域),我得到错误的答复结果。

DAO与修改后的查询(不改变其他代码):

import org.springframework.data.jpa.repository.JpaRepository; 
import org.springframework.data.jpa.repository.Query; 
import org.springframework.data.repository.query.Param; 
import java.util.*; 

public interface TetsModelDAO extends JpaRepository<Samples, Long> 
{ 
    @Query("SELECT s.id, s.name FROM TestModel s WHERE LOWER(s.name) LIKE LOWER(:entry) ORDER BY s.name") 
    List<TestModel> fetchByNameEntry(@Param("entry") String entry); 
} 

在这种情况下的答复是这样的:

1, John, 2, Sam, 3, Ken 

如何优雅地解决这个问题(而无需创建“辅助类” )?

回答

2

您可以从仓库直接返回DTO:

public interface TetsModelDAO extends JpaRepository<Samples, Long> 
{ 
    @Query("SELECT new mypackage.TestDto(s.id, s.name) FROM TestModel s WHERE LOWER(s.name) LIKE LOWER(:entry) ORDER BY s.name") 
    List<TestDto> fetchByNameEntry(@Param("entry") String entry); 
} 

其中TestDto只包含必填字段:

package mypackage; 

public class TestDto { 
    private final long id; 
    private final String name; 

    public TestDto(long id, String name) { 
    this.id = id; 
    this.name = name; 
    } 

    public long getId() { 
    return id; 
    } 

    public String getName() { 
    return name; 
    } 
} 
+0

org.hibernate.hql.internal.ast.QuerySyntaxException:无法找到类[TestDto] [SELECT new TestDto(s.id,s.name)FROM TestModel s WHERE LOWER(s.name)LIKE LOWER(:entry ) 这是什么? Class TestDto与TestDAO相同包 – gorill

+0

您必须在@Query中指定您的类的完整名称(包括包) - 只需将其添加到我的答案 –

+0

非常感谢您的帮助)))) – gorill

0

您的查询不返回TestModel实例。它返回对象数组(即List<Object[]>),每个数组包含ID和找到的名称TestModel。正确的查询是

SELECT s FROM TestModel s WHERE LOWER(s.name) LIKE LOWER(:entry) ORDER BY s.name 

你最好实施自动化测试来检查你的DAO查询返回他们应该做什么。