Convert JSON String to Pretty Print JSON output using Jackson

Question

To indent any old JSON, just bind it as Object, like:

Object json = mapper.readValue(input, Object.class);

and then write it out with indentation:

String indented = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(json);

this avoids your having to define actual POJO to map data to.

Or you can use JsonNode (JSON Tree) as well.

The simplest and also the most compact solution (for v2.3.3):

ObjectMapper mapper = new ObjectMapper();
mapper.enable(SerializationFeature.INDENT_OUTPUT);
mapper.writeValueAsString(obj)

The new way using Jackson 1.9+ is the following:

Object json = OBJECT_MAPPER.readValue(diffResponseJson, Object.class);
String indented = OBJECT_MAPPER.writerWithDefaultPrettyPrinter()
                               .writeValueAsString(json);

The output will be correctly formatted!

For Jackson 1.9, We can use the following code for pretty print.

ObjectMapper objectMapper = new ObjectMapper();
objectMapper.enable(SerializationConfig.Feature.INDENT_OUTPUT);

I think, this is the simplest technique to beautify the json data,

String indented = (new JSONObject(Response)).toString(4);

where Response is a String.

Simply pass the 4(indentSpaces) in toString() method.

Note: It works fine in the android without any library. But in java you have to use the org.json library.

ObjectMapper.readTree() can do this in one line:

mapper.readTree(json).toPrettyString();

Since readTree produces a JsonNode, this should pretty much always produce equivalent pretty-formatted JSON, as it JsonNode is a direct tree representation of the underlying JSON string.

Prior to Jackson 2.10

The JsonNode.toPrettyString() method was added in Jackson 2.10. Prior to that, a second call to the ObjectMapper was needed to write the pretty formatted result:

mapper.writerWithDefaultPrettyPrinter()
        .writeValueAsString(mapper.readTree(json));

You can achieve this using bellow ways:

1. Using Jackson

    String formattedData=new ObjectMapper().writerWithDefaultPrettyPrinter()
.writeValueAsString(YOUR_JSON_OBJECT);

Import bellow class:

import com.fasterxml.jackson.databind.ObjectMapper;

It's gradle dependency is :

compile 'com.fasterxml.jackson.core:jackson-core:2.7.3'
compile 'com.fasterxml.jackson.core:jackson-annotations:2.7.3'
compile 'com.fasterxml.jackson.core:jackson-databind:2.7.3'

2. Using Gson from Google

String formattedData=new GsonBuilder().setPrettyPrinting()
    .create().toJson(YOUR_OBJECT);

Import bellow class:

import com.google.gson.Gson;

It's gradle is:

compile 'com.google.code.gson:gson:2.8.2'

Here, you can also download correct updated version from repository.