我想用java编写一个json文件,但它不起作用,我收到此警告: 我想知道如何执行此操作,因为我要将选项卡式的 cfg 文件转换为 json。
Type safety: The method add(Object) belongs to the raw type ArrayList. References to generic type ArrayList<E> should be parameterized
我有这个代码:
package json;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
public class JsonWriter {
public static void main(String[] args) {
JSONObject countryObj = new JSONObject();
countryObj.put("Name", "India");
countryObj.put("Population", new Integer(1000000));
JSONArray listOfStates = new JSONArray();
listOfStates.add("Madhya Pradesh");
listOfStates.add("Maharastra");
listOfStates.add("Rajasthan");
countryObj.put("States", listOfStates);
try {
// Writing to a file
File file=new File("JsonFile.json");
file.createNewFile();
FileWriter fileWriter = new FileWriter(file);
System.out.println("Writing JSON object to file");
System.out.println("-----------------------");
System.out.print(countryObj);
fileWriter.write(countryObj.toJSONString());
fileWriter.flush();
fileWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
我建议您使用对象创建一个简单的 ArrayList,然后使用序列化器将它们序列化为 JSON(在下面的示例中使用 Jackson 库)。它看起来像这样:
首先,在类中定义模型(为了可读性而没有封装):
public class Country{
public String name;
public Integer population;
public List<String> states;
}
然后您可以继续创建它,并填充列表:
import java.io.File;
import java.io.IOException;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
public class JsonWriter {
public static void main(String[] args) {
Country countryObj = new Country();
countryObj.name = "India";
countryObj.population = 1000000;
List<String> listOfStates = new ArrayList<String>();
listOfStates.add("Madhya Pradesh");
listOfStates.add("Maharastra");
listOfStates.add("Rajasthan");
countryObj.states = listOfStates ;
ObjectMapper mapper = new ObjectMapper();
try {
// Writing to a file
mapper.writeValue(new File("c:\\country.json"), countryObj );
} catch (IOException e) {
e.printStackTrace();
}
}
}
另一种方法是使用 Filelize 编写 json 文件。
Filelizer filelizer = new Filelizer("src/main/resources/");
filelizer.save("India", country);