使用 Jackson 将列表转换为 json

Question

使用以下代码，我已将列表转换为 json，但格式为 如下：

{"GodownMaster":[{"pname":"FCI CHARLAPALLI","pcode":"16042"},
{"pname":"MLS CIRCLE 1 L.B. NAGAR","pcode":"16016"},{"pname":"MLS CIRCLE 4 
AZAMABAD","pcode":"16003"},{"pname":"MLS CIRCLE 6 
VIDYANAGAR","pcode":"16005"},{"pname":"OTHERS","pcode":"1699"}]} 

---

但我想将其转换为：

[{"pname":"FCI CHARLAPALLI","pcode":"16042"},
{"pname":"MLS CIRCLE 1 L.B. NAGAR","pcode":"16016"},{"pname":"MLS CIRCLE 4 
AZAMABAD","pcode":"16003"},{"pname":"MLS CIRCLE 6 
VIDYANAGAR","pcode":"16005"},{"pname":"OTHERS","pcode":"1699"}] 

下面是我的弹簧控制器：

@RequestMapping("/getGodowns")
public @ResponseBody Map 
getGodownsBasedOnDistrict(@RequestParam(value="district_code") String 
dist_code) {

List<CscGodownBean> godown_list = null;
Map<String, List<CscGodownBean>> m = new HashMap();
String exception = null;
try
{
//getting name and codes here
godown_list = scm_service.getGodownListBesedOnDistCode(dist_code);
}catch(Exception ex)
{
ex.printStackTrace();
exception = ex.getMessage();
}

if(godown_list!=null) {
for(int i=0;i<godown_list.size();i++) {
m.put("GodownMaster",godown_list);
}
}
return m;
}

Answer 1

您为什么要将您的列表放入Map？代码看起来很奇怪。如果你想返回一个列表，就这样做吧：

@RequestMapping("/getGodowns")
public @ResponseBody List<CscGodownBean> getGodownsBasedOnDistrict(@RequestParam(value="district_code") String dist_code) {
    List<CscGodownBean> godown_list = null;
    String exception = null;
    try {
        //getting name and codes here
        godown_list = scm_service.getGodownListBesedOnDistCode(dist_code);
    } catch (Exception ex) {
        ex.printStackTrace();
        exception = ex.getMessage();
    }
    return godown_list;
}

Answer 2

将返回结果从Map更改为List<CscGodownBean>并输入：retrun godown_list 所以;

@RequestMapping("/getGodowns")
public @ResponseBody List<CscGodownBean>
getGodownsBasedOnDistrict(@RequestParam(value="district_code") String 
dist_code) {

List<CscGodownBean> godown_list = new ArrayList<CscGodownBean>();
String exception = null;
try
{
    //getting name and codes here
    godown_list = scm_service.getGodownListBesedOnDistCode(dist_code);
}catch(Exception ex)
{
   ex.printStackTrace();
   exception = ex.getMessage();
}

return godown_list ;
}

更新

你可以将结果作为字符串返回，你会得到你需要的：

@RequestMapping("/getGodowns")
public @ResponseBody String
getGodownsBasedOnDistrict(@RequestParam(value="district_code") String 
dist_code) {

List<CscGodownBean> godown_list = new ArrayList<CscGodownBean>();
String exception = null;
try
{
    //getting name and codes here
    godown_list = scm_service.getGodownListBesedOnDistCode(dist_code);
}catch(Exception ex)
{
   ex.printStackTrace();
   exception = ex.getMessage();
}
ObjectMapper objectMapper = new ObjectMapper();
    objectMapper.enable(SerializationFeature.INDENT_OUTPUT);
    String arrayToJson = objectMapper.writeValueAsString(godown_list);
    System.out.println("Convert List to JSON :");
    System.out.println(arrayToJson);

return arrayToJson ;
}

返回的String是json格式。

Answer 3

这是我用过的：

@RequestMapping("/alluserreportJSON")
public @ResponseBody String getusersJSON() {
    ObjectMapper objectMapper = new ObjectMapper();
    //Set pretty printing of json
    objectMapper.enable(SerializationFeature.INDENT_OUTPUT);
    List<AppUser> userlist = null;
    @SuppressWarnings("unused")
    String exception = null;
    String arrayToJson = null;
    try {
        userlist = userService.findAllUsers();
        arrayToJson = objectMapper.writeValueAsString(userlist);
    } catch (Exception ex) {
        ex.printStackTrace();
        exception = ex.getMessage();
    }
    return arrayToJson;
}

希望它可以帮助某人。你可以看到它在here 工作。

Answer 4

您将返回类型添加为 Map，但您仍然想要相同的然后在 ajaxComplete() 中放置代码；

var response = '{"GodownMaster":[{"pname":"FCI CHARLAPALLI","pcode":"16042"}, {"pname":"MLS CIRCLE 1 L.B. NAGAR","pcode":"16016"},{"pname":"MLS CIRCLE 4 AZAMABAD","pcode":"16003"},{"pname":"MLS CIRCLE 6 VIDYANAGAR","pcode":"16005"},{"pname":"OTHERS","pcode":"1699"}]}'


JSON.stringify(JSON.parse(response).GodownMaster);