java properties to json

Question

Is there an easy way to convert properties with dot notation to json

I.E

server.host=foo.bar
server.port=1234

TO

{
         


        

Answer 1

Try reading this http://www.oracle.com/technetwork/articles/java/json-1973242.html, you will find several class to work with json.

I guess that retrieving the json from a local file, inner resource in the jar, or in another location specificable by an URL and the just read it with a JsonReader get the job dones.

---

This is a snipped from the reference site posted before.

 URL url = new URL("https://graph.facebook.com/search?q=java&type=post");
 try (InputStream is = url.openStream();
      JsonReader rdr = Json.createReader(is)) {

      JsonObject obj = rdr.readObject();
      // from this line forward you got what you want :D

     }
 }

Hope it helps!

Answer 2

You can try with https://github.com/mikolajmitura/java-properties-to-json

You can generate Json from:

• from Java properties (java.util.Properties)
• from Map (import java.util.Map) -> Map<String,String>
• from Map (import java.util.Map) -> Map<String,Object>
• from InputStream with properties (java.io.InputStream)
• from given file localization with properties
• from File with properties (java.io.File)

code example:

import pl.jalokim.propertiestojson.util.PropertiesToJsonConverter;

...

Properties properties = ....;
String jsonFromProperties = new PropertiesToJsonConverter().convertToJson(properties);

InputStream inputStream = ....;
String jsonFromInputStream = new PropertiesToJsonConverter().convertToJson(inputStream);

Map<String,String> mapProperties = ....;
String jsonFromInputProperties = new PropertiesToJsonConverter().convertToJson(mapProperties);

Map<String, Object> valuesAsObjectMap = ....;
String jsonFromProperties2 = new PropertiesToJsonConverter().convertFromValuesAsObjectMap(valuesAsObjectMap);

String jsonFromFilePath = new PropertiesToJsonConverter().convertPropertiesFromFileToJson("/home/user/file.properties");

String jsonFromFile = new PropertiesToJsonConverter().convertPropertiesFromFileToJson(new File("/home/user/file.properties"));

maven dependency:

      <dependency>
          <groupId>pl.jalokim.propertiestojson</groupId>
          <artifactId>java-properties-to-json</artifactId>
          <version>5.1.0</version>
      </dependency>

dependency required minimum java 8.

more example of uses on https://github.com/mikolajmitura/java-properties-to-json

Answer 3

I didn't want any dependency on gson and I wanted to return a hierarchical json from a Spring controller so a deep Map was enough for me.

This works for me, just loop over all your keys and pass in an empty map.

void recurseCreateMaps(Map<String, Object> currentMap, String key, String value) {
    if (key.contains(".")) {
        String currentKey = key.split("\\.")[0];

        Map<String, Object> deeperMap;

        if (currentMap.get(currentKey) instanceof Map) {
            deeperMap = (Map<String, Object>) currentMap.get(currentKey);
        } else {
            deeperMap = new HashMap<>();
            currentMap.put(currentKey, deeperMap);
        }

        recurseCreateMaps(deeperMap, key.substring(key.indexOf('.') + 1), value);
    } else {
        currentMap.put(key, value);
    }
}

Answer 4

Personally I used this dependency:

<dependency>
  <groupId>com.fasterxml.jackson.dataformat</groupId>
  <artifactId>jackson-dataformat-properties</artifactId> 
  <version>2.10.2</version>
  <scope>compile</scope>
</dependency>

private static JavaPropsMapper javaPropsMapper = JavaPropsMapper.builder().build();
final JsonNode request = javaPropsMapper.readPropertiesAs(parameters, JsonNode.class);

Try to use schema validation to avoid possible issues in you mapping.

Although, with a simple object mapper it is possible also

Properties properties = new Properties();
properties.put("array", new int[] {1,2,3});
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.writeValueAsString(parameters);

Output

{"fullname":["Foo","Bar"]}