Form Serialization with the DDM IO API

When a form creator saves a form in the Liferay Forms application, the Form object is serialized (converted) into JSON for storage in the Liferay DXP database. That’s the default behavior; if you need the form in a different format, you must write your own serialization and deserialization code. Why would you want to do that? Maybe you think JSON storage is not secure, or you have another tool that can consume the form if it’s in YAML. Whatever your reasons, the form can be stored in any format as long as you write a DDMFormSerializer and its corresponding DDMFormDeserializer with the proper logic.

First consider what form data looks like by default, in JSON. A simple form, My Form, with one text field, Full Name, is first created as a DDMForm Java object, then serialized into JSON for storage in the Liferay DXP database when saved.

        "label":{"en_US":"Full Name"},

From its initial state as a DDMForm Java object, the form is serialized into JSON format, and upon retrieval from the database, it’s deserialized: the JSON object representing the form is translated back into a DDMForm Java object, with all its requisite fields. For example, the JSON for the above example holds each form field in the fields attribute. To translate this back into the necessary DDMForm object, first parse the data contained in the JSON object into an actual form field using your deserialization logic. Here’s the logic from DDMFormJsonDeserializer that parses the JSON "fields" element into a list of DDMFormFields:

protected List<DDMFormField> getDDMFormFields(JSONArray jsonArray)
    throws PortalException {

    List<DDMFormField> ddmFormFields = new ArrayList<>();

    for (int i = 0; i < jsonArray.length(); i++) {
        DDMFormField ddmFormField = getDDMFormField(


    return ddmFormFields;

Now calling DDMForm.setDDMFormFields(ddmFormFields) in the deserializer completes the translation process from the JSON array back to a DDMFormField object that the DDMForm needs.

If you’d like to store forms in a different format, provide custom serialization and deserialization functionality.

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