SpringMVC @RequestBody processing Ajax requests

1 problem description

Recently in the debugging code and found the following problems:

org.springframework.http.converter.HttpMessageNotReadableException: Could not read JSON: Unexpected character ('c' (code 99)): expected a valid value (number, String, array, object, 'true', 'false' or 'null'). 

The front is a Ajax request, the data is a JSON object.

Background found the wrong is generally JSON data format transfer problems.

The object passed to the Java terminal 2

In the SpringMVC environment, @RequestBody receiver is a Json string object, not a Json object. However, in the Ajax request often pass are Json objects, and later found withJSON.stringify(data)The way can the object into a string. At the same time the Ajax request to the specifieddataType: "json",contentType:"application/json"This can easily be an object to the Java end, use @RequestBody to bind objects

3 how will the List object to the Java terminal:

<script type="text/javascript">  
    $(document).ready(function(){  
        var saveDataAry=[];  
        var data1={"userName":"test","address":"gz"};  
        var data2={"userName":"ququ","address":"gr"};  
        saveDataAry.push(data1);  
        saveDataAry.push(data2);         
        $.ajax({ 
            type:"POST", 
            url:"user/saveUser", 
            dataType:"json",      
            contentType:"application/json",               
            data:JSON.stringify(saveData), 
            success:function(data){ 
                                       
            } 
         }); 
    });  
</script> 

JSON.stringify() : Convert the object to a JSON string.

JSON.parse(): The string JSON is converted to JSON objects.

Java:

@RequestMapping(value = "saveUser", method = {RequestMethod.POST }}) 
    @ResponseBody  
    public void saveUser(@RequestBody List<User> users) { 
         userService.batchSave(users); 
    } 

This is not possible. Because spring MVC does not automatically translate into a List object. To the background, List is of type LinkedHashMap.

But using the array can receive User[], as follows:

@RequestMapping(value = "saveUser", method = {RequestMethod.POST }}) 
    @ResponseBody  
    public void saveUser(@RequestBody User[] users) { 
         userService.batchSave(users); 
    }