Pretty printing JSON from Jackson 2.2's ObjectMapper

Detailed Configuration

String Refactoring

Let's say you have an ugly duckling String containing JSON and you want it to become a beautiful swan. Use the writerWithDefaultPrettyPrinter method:

// "Fairytale transformation in progress..."
String prettyJsonString = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(jsonInstance);
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Writing to Files

You can write your beautified JSON directly to a file, like keeping a photograph of your object's best look:

// "Your JSON is now runway ready!"
mapper.writerWithDefaultPrettyPrinter().writeValue(new File("output.json"), yourObject); // Behold, a JSON star is born!
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Gson: The Alternative

If you don't mind trying on a new fashion with Gson, here's how it offers pretty printing:

String json = new GsonBuilder().setPrettyPrinting().create().toJson(yourObject); // JSON on the catwalk!
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From File to Fancy

Here's how to read a Plain Jane JSON file and transform it into a prom queen pretty-printed JSON String:

byte[] jsonData = Files.readAllBytes(Paths.get(filePath)); 
YourClass yourObject = objectMapper.readValue(jsonData, YourClass.class);
String prettyJson = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(yourObject); // Prom night, here we come!
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Deep Dive into ObjectMapper

Playing Safe

While working with ObjectMapper, remember those good manners:

• Your classes need proper getters and setters.
• Handle the exceptions that may feel like party crashers.

Set the Tone

You can add your personal touch with custom indentation. More like choosing the music for your JSON party:

DefaultPrettyPrinter printer = new DefaultPrettyPrinter().withIndent("    "); // 4 spaces, the perfect party rhythm!
String customPrettyJson = mapper.writer(printer).writeValueAsString(yourObject);
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Power of Parsing

ObjectMapper is powerful. It not only writes but reads JSON bravely:

YourClass obj = mapper.readValue(jsonString, YourClass.class); // Like reading a thrilling adventure novel.
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It's versatile and can parse from Strings, Files, Streams and more.

Console Output

For that quick photo snap or to showoff your pretty JSON, print it to the console:

System.out.println(prettyJson); // "Look at my JSON, my JSON is amazing!"
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Ensure you dance with the right version of Jackson for your pretty printing moves.