jason by gson复习

来源：互联网发布：智能电视点播软件编辑：程序博客网时间：2024/05/16 15:46

把gson-x.x.x.jar添加到工程。
jason读：

test.json

  {    "cat":"it",    "languages":[        {"id":1,"ide":"eclipse","name":"java"},        {"id":2,"ide":"xcode","name":"swift"},        {"id":3,"ide":"visual studio","name":"c#"}    ],    "pop":true}

java代码读取json文件：

package test;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 ReadJason {    public static void main(String[] args) {        try {            JsonParser parser= new JsonParser();            JsonObject object=(JsonObject) parser.parse(new FileReader("test.json"));            System.out.println("cat="+object.get("cat").getAsString());            System.out.println("pop="+object.get("pop").getAsBoolean());            JsonArray array=object.get("languages").getAsJsonArray();            for(int i=0;i<array.size();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();        }    }}

结果输出：

cat=itpop=true------------id=1name=javaide=eclipse------------id=2name=swiftide=xcode------------id=3name=c#ide=visual studio

json写出上式test.json文件:注意jre不可过低，否则部分方法出问题。

package test;import com.google.gson.JsonArray;import com.google.gson.JsonObject;public class JsonWrite {    public static void main(String[] args) {        JsonObject object =new JsonObject();        object.addProperty("cat", "it");         JsonArray array =new JsonArray();        JsonObject lan1=new JsonObject();        lan1.addProperty("id",1);        lan1.addProperty("name", "java");        lan1.addProperty("ide", "eclipse");        array.add(lan1);        JsonObject lan2=new JsonObject();        lan2.addProperty("id",2);        lan2.addProperty("name", "swift");        lan2.addProperty("ide", "xcode");        array.add(lan2);        JsonObject lan3=new JsonObject();        lan3.addProperty("id",3);        lan3.addProperty("name", "c#");        lan3.addProperty("ide", "visual studio");        array.add(lan3);        object.add("languages",array);        object.addProperty("pop",true);        System.out.println(object.toString());    }}

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