Question

这是JAVA中的代码，我使用了JSONArray和方法JSONarray.put(string);

public JSONArray getChart() {
    Connection con = getConnectionObject();
    Statement st = null;
    ResultSet rs = null;
    JSONObject jCharto = new JSONObject();
    JSONArray arr = new JSONArray();



    try {
        st = con.createStatement();         
        String query  = "select count(books_issued) as books_issued,command from fact_aaglib, school where fact_aaglib.school_name = school.school_name group by command;";


        rs = st.executeQuery(query);
        System.out.println("['Command','Book Issued'],");
         while (rs.next())  
                {                                                                                                   

                String zone = rs.getString("command");
                arr.put(zone);

                int booksissued = rs.getInt("books_issued");

                arr.put(booksissued);


                }
         System.out.println(arr+",");

    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (con != null)
                con.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
}   
return arr; 
}

这是我的输出

['Command','Book Issued'],["Central",324,"Southern",312,"South-West",192,"Eastern",264,"Northern",84,"Western",396],

但实际上我想要这样的输出：

[
    ['Command', 'Books Issued'],
    ["Central",324],["Southern",312],
    ["South-West",192], 
    ["Eastern",264], 
    ["Northern",84],
    ["Western",396]
]

此数据用于在谷歌图表中绘制条形图。

Answer 1

JSONArray不限于字符串。

您需要创建一个用于保存记录的数组，然后为每对或多个记录创建一个新数组。这是基本的想法：

// create the "top" array
JSONArray topArray = new JSONArray();

// add your static "headers"
JSONArray headers = new JSONArray();
headers.put("Command");
headers.put("Book Issued");
topArray.put(headers);

while (rs.next()){   
    // create a new array for the current record
    JSONArray recordArray = new JSONArray(); 
    // populate the record array                                                                                             
    String zone = rs.getString("command");
    recordArray.put(zone);
    int booksissued = rs.getInt("books_issued");
    recordArray.put(booksissued);

    // append the record array to the top array
    topArray.put(recordArray);
}

return topArray;

使用JSON的数组内的数组

1 个答案: