以有效的 JSON 返回字符串

Question

I want to return valid json string.

Ex:

{
 "status":"Success",
 "total_amt": "41",
 "igst_amt": 14,
 "sgst_amt": 0,
 "cgst_amt": "12",
 "cess_amt": 15
}

Expected:

{
 "status":"Success",
 "total_amt": "41",
 "igst_amt": "14",
 "sgst_amt": "0",
 "cgst_amt": "12",
 "cess_amt": "15"
} 

I have wrote below code:

public String toString() {
    return "{\"status\":\"" + status + "\",\"total_amt\":\"" + total_amt + "\",\"igst_amt\":\"" + igst_amt
        + "\",\"sgst_amt\":\"" + sgst_amt + "\",\"cgst_amt:\"" + cgst_amt + "\",\"cess_amt\":\"" + cess_amt + "\"}";
}

It is not returning valid JSON.

Answer 1

You can use a third party lib. This example uses GSON

class Result {
 private String status;

 @SerializedName("total_amt")
 private int totalAmount;

 @SerializedName("igst_amt")
 private int igstAmount;

 @SerializedName("sgst_amt")
 private int sgstAmount;

 @SerializedName("cgst_amt")
 private int cgstAmount;

 @SerializedName("cess_amt")
 private int cessAmount;

 public Result() {}
} 

Result result = new Result();
// set your fields
String json = new Gson().toJson(result);

Answer 2

Read about gson for returning json format. link to gson github

To simple use it you can:

 final Gson gson  = new GsonBuilder().setPrettyPrinting().create();
 final String string = "you string";
 return gson.toJson(string);

Answer 3

I hope igst_amt, sgst_amt and cess_amt are Integers.

So you add .toString() to them

public String toString() {
    return "{\"status\":\"" + status + "\",\"total_amt\":\"" + total_amt + "\",\"igst_amt\":\"" + igst_amt.toString()
        + "\",\"sgst_amt\":\"" + sgst_amt.toString() + "\",\"cgst_amt:\"" + cgst_amt + "\",\"cess_amt\":\"" + cess_amt.toString() + "\"}";
}