java - 将 JSON 转换为 XML，而不将十进制转换为科学记数法

Question

我正在尝试转换JSON至XML在中间件工具中。我正在使用Jackson图书馆来进行这种转变。问题在于，对于 8 中的十进制字段(长度超过 JSON ) ，对应XML值转换为科学记数法。例如8765431002.13转换为8.76543100213E8 .

如果知道字段名称，我可以将科学记数法转换为正常的十进制格式。但就我而言，中间件应用程序不会知道以十进制形式出现的字段。

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

import com.fasterxml.jackson.dataformat.xml.XmlMapper;


public class JSONDataformat {

       public static void main(String[] args) {
              // TODO Auto-generated method stub
              try {
              //String jsonString = "{\"Field1\":18629920.68,\"Field3\":\"test\", \"Field2\":\"null\"}";          
                ObjectMapper objectMapper = new ObjectMapper();
              ObjectMapper xmlMapper = new XmlMapper();
              JsonNode tree = objectMapper.readTree(jsonString);

              String jsonAsXml = xmlMapper.writer().writeValueAsString(tree);
              System.out.println(jsonAsXml);
              }
              catch(Exception e) {e.printStackTrace(); }

       }

}

输出

<ObjectNode xmlns=""><Field1>1.862992068E7</Field1><Field3>test</Field3><Field2/></ObjectNode>

我预计会得到<Field1>值为 18629920.68在上面的代码中。

Answer 1

您需要启用USE_BIG_DECIMAL_FOR_FLOATS特点:

ObjectMapper objectMapper = new ObjectMapper();
objectMapper.enable(DeserializationFeature.USE_BIG_DECIMAL_FOR_FLOATS);

编辑

import com.fasterxml.jackson.core.JsonGenerator.Feature;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;
import java.io.IOException;

public class Test {

    public static void main(String[] args) throws IOException {
        String jsonString = "{\"Field1\": 20121220.00,\"Field3\":\"test\", \"Field2\":\"null\"}";

        ObjectMapper jsonMapper = new ObjectMapper();
        jsonMapper.enable(DeserializationFeature.USE_BIG_DECIMAL_FOR_FLOATS);

        XmlMapper xmlMapper = new XmlMapper();

        JsonNode tree = jsonMapper.readTree(jsonString);

        String jsonAsXml = xmlMapper.writer().with(Feature.WRITE_BIGDECIMAL_AS_PLAIN).writeValueAsString(tree);
        System.out.println(jsonAsXml);
    }
}

上面的代码打印:

<ObjectNode><Field1>20121220</Field1><Field3>test</Field3><Field2>null</Field2></ObjectNode>