Jackson Module HTTP Query

A jackson module for allowing HTTP queries to be represented as typed objects

Installation

To install from Maven Central:

<dependency>
  <groupId>com.github.trickl</groupId>
  <artifactId>jackson-module-httpquery</artifactId>
  <version>1.0.2</version>
</dependency>

Registering module

Like all standard Jackson modules (libraries that implement Module interface), registration is done as follows:

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new HttpQueryModule());

after which functionality is available for all normal Jackson operations.

Purpose

Converts POJOs to query strings and vice versa.

• Use type objects for convenient conversion to query strings (and back).
• Less boilerplate code required for supporting a variety of query combinations.
• Supports existing Jackson JSON annotations for formatting.
• Extra annotations allow for different strategies on handling multi-valued parameters.

Usage Example

@HttpQuery
private static class TypedExample {
    private String valueA;

    private String valueB;

    private int valueC;
}

// To produce "?valueA=test&valueB=testB&valueC=123"...
TypedQuery typed = new TypedQuery(... // omitted for brevity
String queryString = objectMapper.valueToTree(typedQuery).textValue();

Features

• Supports many Jackson annotations
  • @JsonProperty (have a different query parameter name from the variable name).
  • @JsonIgnore (don't serialize a property)
  • @JsonFormat (useful for date strings).
• Supports new parameters
  • @HttpQuery (required to serialize to a query string, not a JSON object).
  • @HttpQueryDelimited (serialize a multi valued property using a delimited list e.g "?values=1,2,3").
  • @HttpQueryNoValue (allow boolean valueless params, e.g. "?debug")