Package org.eel.kitchen.jsonschema.syntax

Schema syntax validation package

See: Description

Interface Summary

Interface	Description
SyntaxChecker	Interface implemented by all syntax checkers

Class Summary

Class	Description
ModZeroSyntaxChecker	Syntax checker for the divisibleBy keyword (draft v3) and multipleOf keyword (draft v4)
PositiveIntegerSyntaxChecker	Syntax validator for keywords having a positive integer value as an argument
SimpleSyntaxChecker	Simple type-only syntax checker
SyntaxValidator	Schema syntax validator

Package org.eel.kitchen.jsonschema.syntax Description

Schema syntax validation package

The main class in this package is SyntaxValidator.

Syntax validation has a critically important role in the validation process. An invalid schema will always fail to validate a JSON instance.

For this implementation in particular, it also helps to ensure that the KeywordValidator associated with the schema keyword does not need to preoccupy about its arguments being well-formed: it is the contract of syntax validation that a keyword validator needs not preoccupy about this when it is instantiated.

Unlike keyword validators, syntax validators are not built by reflection. It is therefore your responsibility to instantiate it and only then register it.

Here is an example code for a hypothetic foo keyword which must have a string as an argument, and this string must be at least 5 characters long:

  public final class SyntaxCheckerImpl
      implements SyntaxChecker
  {
      @Override
      public void checkSyntax(final Message.Builder msg,
          final List<String> messages, final JsonNode schema)
      {
          final JsonNode node = schema.get(keyword);
          if (!node.isTextual()) {
              msg.setMessage("field is not a string");
              messages.add(msg.build());
              return;
          }

          if (node.textValue().length() >= 5)
              return;

          msg.setMessage("field has insufficient length")
              .addInfo("required", 5)
              .addInfo("found", node.textValue().length());
          messages.add(msg.build());
      }
  }
 

For more information, see SyntaxChecker and Message.