後臺作為傳輸資料的格式，將資料傳輸到客戶端。JSON有兩種格式，一種是物件格式的，另一種是陣列格式的。

下面是一組json字串：

String json="{"resultcode":"200","reason":"Return Successd!","result":{"province":"北京","city":"","areacode":"010",
"zip":"100000","company":"聯通","card":""},"error_code":0}"

1.我們按json原生解析的方法一步一步進行解析：

JSONObject jsonObject = new JSONObject(json);
        JSONObject object = jsonObject.getJSONObject("result");
	String province=object.getString("province");
	String city=object.getString("city");
	String areacode=object.getString("areacode");
 

public class Root<T> {
	private String resultcode;
	private String reason;
	private T result;
	private int error_code;
	public void setResultcode(String resultcode){
		this.resultcode = resultcode;
}
	public String getResultcode(){
return this.resultcode;
}
public void setReason(String reason){
this.reason = reason;
}
public String getReason(){
return this.reason;
	}
public void setResult(T result){
this.result = result;
	}
public T getResult(){
return this.result;
}
public void setError_code(int error_code){
this.error_code = error_code;
}
public int getError_code(){
	return this.error_code;
}
}
 

public class result {
    private String province;
    private String city;
    private String areacode;
    private String zip;
    private String company;
    private String card;
    public String getProvince() {
        return province;
    }
    public void setProvince(String province) {
        this.province = province;
    }
    public String getCity() {
        return city;
    }
    public void setCity(String city) {
        this.city = city;
    }
    public String getZip() {
        return zip;
    }
    public void setZip(String zip) {
        this.zip = zip;
    }
    public String getAreacode() {
        return areacode;
    }
    public void setAreacode(String areacode) {
        this.areacode = areacode;
    }
    public String getCompany() {
        return company;
    }
    public void setCompany(String company) {
        this.company = company;
    }
    public String getCard() {
        return card;
    }
    public void setCard(String card) {
        this.card = card;
    }
}
 

JSONObject jsonObject=JSONObject.fromObject(json);
Root root=(Root)JSONObject.toBean(jsonObject, Root.class);

	Root<JSON> root=JSONObject.parseObject(json,Root.class);
        Result result =JSONObject.toJavaObject(root.getResult(),Result.class);

	Gson gson=new Gson();
        Type userType = new TypeToken<Root<Result>>(){}.getType();//用於獲取泛型資訊
        Root<Result> root=gson.fromJson(json, userType);
	Result result=root.getResult();

String json="{"resultcode":"200","reason":"Return Successd!","result":[{"province":"北京","city":"","areacode":"010",
"zip":"100000","company":"聯通","card":""},{"province":"北京","city":"","areacode":"010",
"zip":"100000","company":"聯通","card":""}],"error_code":0}"

Gson gson=new Gson();
        Type userType = new TypeToken<Root<List<Result>>>(){}.getType();
        Root<List<Result>> root=gson.fromJson(json, userType);
        List<Result> result=root.getResult();

	Root<JSON> root=JSONObject.parseObject(json,Root.class);
        List<Result> result =JSONObject.parseArray(root.getResult().toJSONString(),Result.class);

將json陣列轉換為list物件：

String str="[{"name":"真實伺服器","ip":"101.37.168.121","port":5672,"username":"shanghu","password":"GY5P20u1ix9vK8DI","isdemo":false},
        {"name":"模擬伺服器","ip":"101.37.34.221","port":5672,"username":"shanghu","password":"GY5P20u1ix9vK8DI","isdemo":true}]";

	Gson gson=new Gson();
	Service[] array = gson.fromJson(str, Service[].class);
	List<Service> service=Arrays.asList(array);

List<Service> service=JSONArray.parseArray(str, Service.class);