在使用第三方api的使用，有时候会从网络中获得json数据，所以说我们将如何解析json数据？

下面小编将通过以下几点来进行json的讲解

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It is easy for humans to read and write. It is easy for machines to parse and generate. It is based on a subset of theJavaScript Programming Language,Standard ECMA-262 3rd Edition - December 1999. JSON is a text format that is completely language independent but uses conventions that are familiar to programmers of the C-family of languages, including C, C++, C#, Java, JavaScript, Perl, Python, and many others. These properties make JSON an ideal data-interchange language.

2.Json数据类型

2-1.json对象

2-2.json数组

ps：JSONObject与JSONArray的区别

(JSON数组)

(JSON数组)

3.解析JSON数据(小编使用的GSON进行json数据的解析)

3-1 【JSONObject的解析】

下面是一个json文件：

{

"resultcode": "200",

"reason": "successed!",

"result": {

"sk": {

"temp": "24",

"wind_direction": "西南风",

"wind_strength": "2级",

"humidity": "51%",

"time": "10:11"

},

"today": {

"temperature": "16℃~27℃",

"weather": "阴转多云",

"weather_id": {

"fa": "02",

"fb": "01"

},

"wind": "西南风3-4 级",

"week": "星期四",

"city": "滨州",

"date_y": "2015年06月04日",

"dressing_index": "舒适",

"dressing_advice": "建议着长袖T恤、衬衫加单裤等服装。年老体弱者宜着针织长袖衬衫、马甲和长裤。",

"uv_index": "最弱",

"comfort_index": "",

"wash_index": "较适宜",

"travel_index": "",

"exercise_index": "较适宜",

"drying_index": ""

},

"future": [

{

"temperature": "16℃~27℃",

"weather": "阴转多云",

"weather_id": {

"fa": "02",

"fb": "01"

},

"wind": "西南风3-4 级",

"week": "星期四",

"date": "20150604"

},

{

"temperature": "20℃~32℃",

"weather": "多云转晴",

"weather_id": {

"fa": "01",

"fb": "00"

},

"wind": "西风3-4 级",

"week": "星期五",

"date": "20150605"

},

{

"temperature": "23℃~35℃",

"weather": "多云转阴",

"weather_id": {

"fa": "01",

"fb": "02"

},

"wind": "西南风3-4 级",

"week": "星期六",

"date": "20150606"

},

{

"temperature": "20℃~33℃",

"weather": "多云",

"weather_id": {

"fa": "01",

"fb": "01"

},

"wind": "北风微风",

"week": "星期日",

"date": "20150607"

},

{

"temperature": "22℃~34℃",

"weather": "多云",

"weather_id": {

"fa": "01",

"fb": "01"

},

"wind": "西南风3-4 级",

"week": "星期一",

"date": "20150608"

},

{

"temperature": "22℃~33℃",

"weather": "阴",

"weather_id": {

"fa": "02",

"fb": "02"

},

"wind": "西南风3-4 级",

"week": "星期二",

"date": "20150609"

},

{

"temperature": "22℃~33℃",

"weather": "多云",

"weather_id": {

"fa": "01",

"fb": "01"

},

"wind": "南风3-4 级",

"week": "星期三",

"date": "20150610"

}

]

},

"error_code": 0

}

我们进行解析(解析一部分)：

package cn.edu.bzu.json;

import java.io.FileNotFoundException;

import java.io.FileReader;

import com.google.gson.JsonArray;

import com.google.gson.JsonIOException;

import com.google.gson.JsonObject;

import com.google.gson.JsonParser;

import com.google.gson.JsonSyntaxException;

public class Read {

public static void main(String args[]){

JsonParser parse =new JsonParser(); //创建json解析器

try {

JsonObject json=(JsonObject) parse.parse(new FileReader("weather.json")); //创建jsonObject对象

System.out.println("resultcode:"+json.get("resultcode").getAsInt()); //将json数据转为为int型的数据

System.out.println("reason:"+json.get("reason").getAsString()); //将json数据转为为String型的数据

JsonObject result=json.get("result").getAsJsonObject();

JsonObject today=result.get("today").getAsJsonObject();

System.out.println("temperature:"+today.get("temperature").getAsString());

System.out.println("weather:"+today.get("weather").getAsString());

} catch (JsonIOException e) {

e.printStackTrace();

} catch (JsonSyntaxException e) {

e.printStackTrace();

} catch (FileNotFoundException e) {

e.printStackTrace();

}

}

}

输出结果：

3-2 【JSONArray的解析】

下面是一个json文件

{"cat":"it","language":[

{"id":1,"ide":"eclipse","name":Java},

{"id":2,"ide":"XCode","name":"Swift"},

{"id":3,"ide":"Visual Stdio","name":"C#"}

],"pop":true}

我们进行解析：

package cn.edu.bzu.json;

import java.io.FileNotFoundException;

import java.io.FileReader;

import com.google.gson.JsonArray;

import com.google.gson.JsonIOException;

import com.google.gson.JsonObject;

import com.google.gson.JsonParser;

import com.google.gson.JsonSyntaxException;

public class ReadJSON {

public static void main(String args[]){

try {

JsonParser parser=new JsonParser(); //创建JSON解析器

JsonObject object=(JsonObject) parser.parse(new FileReader("test.json")); //创建JsonObject对象

System.out.println("cat="+object.get("cat").getAsString()); //将json数据转为为String型的数据

System.out.println("pop="+object.get("pop").getAsBoolean()); //将json数据转为为boolean型的数据

JsonArray array=object.get("language").getAsJsonArray(); //得到为json的数组

for(int i=0;i

System.out.println("---------------");

JsonObject subObject=array.get(i).getAsJsonObject();

System.out.println("id="+subObject.get("id").getAsInt());

System.out.println("name="+subObject.get("name").getAsString());

System.out.println("ide="+subObject.get("ide").getAsString());

}

} catch (JsonIOException e) {

e.printStackTrace();

} catch (JsonSyntaxException e) {

e.printStackTrace();

} catch (FileNotFoundException e) {

e.printStackTrace();

}

}

}

输出结果：

3-3 【分析】

我们通过Gson进行解析，所以在使用前需要导入Gson.jar

解析json数据时，

1.需要进行创建Gson解析器

2.创建JSONObject对象

3.将json数据转为为相应的数据

4.源代码下载：