将Json字符串转换为对象数组

Question

我有一个作为字符串的JSON数组

[
        {
        "id":"1",   
            "lat": "23.053",
            "long": "72.629",
            "location": "ABC",
            "address": "DEF",
            "city": "Ahmedabad",
            "state": "Gujrat",
            "phonenumber": "1234567"
        },
        {
        "id":"2",   
            "lat": "23.053",
            "long": "72.629",
            "location": "ABC",
            "address": "DEF",
            "city": "Ahmedabad",
            "state": "Gujrat",
            "phonenumber": "1234567"
        },
        {
            "id":"3",   
        "lat": "23.053",
            "long": "72.629",
            "location": "ABC",
            "address": "DEF",
            "city": "Ahmedabad",
            "state": "Gujrat",
            "phonenumber": "1234567"
        },
        {
            "id":"4",   
        "lat": "23.053",
            "long": "72.629",
            "location": "ABC",
            "address": "DEF",
            "city": "Ahmedabad",
            "state": "Gujrat",
            "phonenumber": "1234567"
        },
        {
            "id":"5",   
        "lat": "23.053",
            "long": "72.629",
            "location": "ABC",
            "address": "DEF",
            "city": "Ahmedabad",
            "state": "Gujrat",
            "phonenumber": "1234567"
        }
]

我希望将此字符串转换为每个json对象。我有一个地址类。我应该如何将这个json字符串转换为对象？

我尝试过：

Address address = gson.fromJson(addressJson, Address.class);

com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2
    com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:176)
    com.google.gson.Gson.fromJson(Gson.java:803)
    com.google.gson.Gson.fromJson(Gson.java:768)
    com.google.gson.Gson.fromJson(Gson.java:717)
    com.google.gson.Gson.fromJson(Gson.java:689)

- jackyesind

---

可能是https://dev59.com/eWbWa4cB1Zd3GeqPTymR的重复问题。 - muthu

@muthu 不，那不是Gson。 - Brian

Answer 1

试一下这个

Address[] address = gson.fromJson(addressJson, Address[].class);

- Narendra Pathai

---

此外，如果更喜欢使用像 List 这样的集合类型，可以将 fromJson 方法调用封装在 Arrays.asList 中。 - Brian

它正在工作，但是对于同一件事情，我有一个日期字段，其值为“Tue Aug 27 06:07:32 UTC 2013”。它显示错误：“java.text.ParseException：无法解析的日期：”Tue Aug 27 11:37:32 IST 2013“ java.text.DateFormat.parse（DateFormat.java:337）” - jackyesind

请查看此链接以了解详情：https://dev59.com/rWw15IYBdhLWcg3wCXOJ 您需要更改GSON的默认日期格式。 - Narendra Pathai

谢谢！这非常有用！ - Alexander Gapanowich

Answer 2

通过使用 Jackson 库中的 ObjectMapper 类，你可以读取数值并将其映射到一个对象或对象数组。

final ObjectMapper objectMapper = new ObjectMapper();
Address [] mdls = objectMapper.readValue(addressJson, Address [].class);

对于 List<Address>，请使用以下内容：

List<Address> mdls = objectMapper.readValue(addressJson, new TypeReference<List<Address>>() {});

- TiyebM