Question

我正在尝试将Json数组传递给Grails控制器，然后传递给Java类。我无法弄清楚如何正确地将我的参数传递给Java类。这是相关代码。

AJAX POST：

  $('#matrixForm').submit(function(e) {
        e.preventDefault();

    var matrixArray = $(this).serializeArray();

    $.ajax({  
        type: "POST",  
        data: matrixArray,  
        url: "/turingpages/factorize/create",
        success: function(data) {
            //USE DATA
        }  
    });  
    });

Grails控制器：

...
    def create() {

        MatrixFactorization m = new MatrixFactorization(params)
        Gson gson = new Gson()
        def jsonMatrix = gson.toJson(m.answer)
        render jsonMatrix
    }
...

MatrixFactorization构造函数：

public MatrixFactorization(JsonElement jsonarray) {
    BlockRealMatrix R = GsonMatrix.toMatrix(jsonarray);
    this.run(R);
}

我的控制台将我的Json数组显示为：

[{name:"00", value:"1"}, {name:"01", value:"2"}, {name:"02", value:"3"}, {name:"10", value:"4"}, {name:"11", value:"0"}, {name:"12", value:"4"}, {name:"20", value:"0"}, {name:"21", value:"4"}, {name:"22", value:"2"}]

我的堆栈跟踪是：

| Error 2013-01-18 00:30:23,792 [http-bio-8080-exec-4] ERROR errors.GrailsExceptionResolver  - GroovyRuntimeException occurred when processing request: [POST] /turingpages/factorize/create - parameters:
21: 4
20: 0
10: 4
22: 2
00: 1
01: 2
11: 0
02: 3
12: 4
failed to invoke constructor: public matrices.MatrixFactorization(com.google.gson.JsonElement) with arguments: [] reason: java.lang.IllegalArgumentException: wrong number of arguments. Stacktrace follows:
Message: failed to invoke constructor: public matrices.MatrixFactorization(com.google.gson.JsonElement) with arguments: [] reason: java.lang.IllegalArgumentException: wrong number of arguments
    Line | Method
->>   15 | create    in turingpages.rest.MFController$$ENuqtska
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|    195 | doFilter  in grails.plugin.cache.web.filter.PageFragmentCachingFilter
|     63 | doFilter  in grails.plugin.cache.web.filter.AbstractFilter
|   1110 | runWorker in java.util.concurrent.ThreadPoolExecutor
|    603 | run . . . in java.util.concurrent.ThreadPoolExecutor$Worker
^    722 | run       in java.lang.Thread

我是使用JSON的新手。任何帮助表示赞赏。感谢。

Answer 1

1

默认情况下，jQuery会将此数据作为请求参数传递，而不是JSON。所以你应该构建一个JSON字符串来传递给jQuery。我可以推荐你JSON 3 library。在这种情况下，它将是：

$.ajax({  
    type: "POST",  
    data: JSON.stringify(matrixArray),  
    url: "/turingpages/factorize/create",
    success: function(data) {
        //USE DATA
    }  
});

2

在服务器端，您也可以使用标准的Grails JSON转换器（但如果您愿意，可以使用Gson），请参阅http://grails.org/Converters+Reference。

在这种情况下，您可以使用

def create() {
    MatrixFactorization m = new MatrixFactorization(request.JSON)
    render m.answer as JSON
}

Json作为Grails控制器的参数

1 个答案: