Java: JSONObject.toString() - 在冒号后添加额外的空格 (":" -> ": ")

Question

Been googling a while but haven't found anything useful since keywords are too common.

Currently in my Java code method toString() (called on some JSONObject object) produces output like this:

{"key_name":<numerical_value>}

while what I need (due to the fact that parser on the other side of the project is imperfect) is:

{"key_name": <numerical_value>}

The only difference is that extra space after colon. Is there any JSONObject builtin way to do it or do I need some handwritten simple string operation for it?

Answer 1

I can only imagine building a custom JSONStringer . In fact, it could be a JSONWriter built using a StringWriter . Then you override all the value methods to add a space before calling parent class method.

class JSONSpaceStringer extends JSONWriter {
    private StringWriter sw;

    JSONSpaceStringer(StringWriter sw) {
        parent(sw); // initialize parent
        this.sw = sw;
    }

    @Override
    public JSONWriter value(long l) throws JSONException {
        sw.write(" "); // add an initial space
        parent.value(l); // and let parent class do the job...
    }

// same for all other value methods
//...
}

Answer 2

use the below code. it will help you to solve the problem.

 package com.javamad.utils;

    import java.io.IOException;

    import org.apache.log4j.Logger;
    import org.codehaus.jackson.JsonGenerationException;
    import org.codehaus.jackson.JsonParseException;
    import org.codehaus.jackson.map.JsonMappingException;
    import org.codehaus.jackson.map.ObjectMapper;

    public class JsonUtils {

        private static Logger logger = Logger.getLogger(JsonUtils.class.getName());


        public static <T> T jsonToJavaObject(String jsonRequest, Class<T> valueType)
                throws JsonParseException, JsonMappingException, IOException {
            ObjectMapper objectMapper = new ObjectMapper();
            objectMapper.configure(org.codehaus.jackson.map.DeserializationConfig.Feature.UNWRAP_ROOT_VALUE,false);     
            T finalJavaRequest = objectMapper.readValue(jsonRequest, valueType);
            return finalJavaRequest;

        }

        public static String javaToJson(Object o) {
            String jsonString = null;
            try {
                ObjectMapper objectMapper = new ObjectMapper();
                objectMapper.configure(org.codehaus.jackson.map.DeserializationConfig.Feature.UNWRAP_ROOT_VALUE,true);  
                jsonString = objectMapper.writeValueAsString(o);

            } catch (JsonGenerationException e) {
                logger.error(e);
            } catch (JsonMappingException e) {
                logger.error(e);
            } catch (IOException e) {
                logger.error(e);
            }
            return jsonString;
        }

    }