com.github.fge.jsonschema.examples

Class Example9

java.lang.Object

com.github.fge.jsonschema.examples.ExampleBase

com.github.fge.jsonschema.examples.Example9

public final class Example9
extends ExampleBase

Ninth example: augmenting schemas with custom keywords

link to source code

link to schema

This example adds a custom keyword with syntax checking, digesting and keyword validation. The chosen keyword is divisors: it applies to integer values and takes an array of (unique) integers as an argument.

The validation is the same as for multipleOf except that it is restricted to integer values and the instance must be a multiple of all divisors. For instance, if the value of this keyword is [2, 3], then 6 validates successfully but 14 does not (it is divisible by 2 but not 3).

For this, you need to create your own keyword. This is done using Keyword.newBuilder(String), where the argument is the name of your keyword, and then add the following elements:

• a SyntaxChecker (using KeywordBuilder.withSyntaxChecker(SyntaxChecker);
• a Digester (using KeywordBuilder.withDigester(Digester);
• and finally, a KeywordValidator (using KeywordBuilder.withValidatorClass(Class).

Then, as in Example8, you need to get hold of a Library (we choose again to extend the draft v4 library) and add the (frozen) keyword to it using LibraryBuilder.addKeyword(Keyword).

The keyword validator must have a single constructor taking a JsonNode as an argument (which will be the result of the Digester). Note that you may omit to write a digester and choose instead to use an IdentityDigester or a SimpleDigester (which you inject into a keyword using KeywordBuilder.withIdentityDigester(NodeType, NodeType...) and KeywordBuilder.withSimpleDigester(NodeType, NodeType...) respectively).

Two sample files are given: the first (link) is valid, the other (link) isn't (the first and third elements fail to divide by one or more factors).

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Example9.DivisorsKeywordValidator Custom keyword validator for Example9 It must be public because it is built by reflection.

Constructor Summary

Constructors

Constructor and Description
Example9()

Method Summary

Modifier and Type	Method and Description
static void	main(String... args)

Methods inherited from class com.github.fge.jsonschema.examples.ExampleBase

loadResource, printReport

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Example9

public Example9()

Method Detail

main

public static void main(String... args)
                 throws IOException,
                        com.github.fge.jsonschema.exceptions.ProcessingException

Throws:

IOException

com.github.fge.jsonschema.exceptions.ProcessingException