JITSon aka Jsonassist

This is a very simple POJO to JSON converter using Javaassit for dynamic converter generator.

Performance in some use cases is 2-10 (!) times higher than GSON.

Features

• Primitives, primitive collections, nulls
• Simple objects, nested objects, objects with collections
• Recursive objects
• Supports getters / Bean objects
• Tested

Conclusions about Javassist

• Supports only Java 1.4 syntax
  • No Generics
  • No lambda expressions

How to run

mvn compile exec:java - do nothing actually

mvn compile test

Generated code

Jitson generates conversion methods for each class, some examples:

Simple object

    public String toJson(net.piotrl.jvm.jsonassist.mock.PlainPrimitives o) {
        return "{" + "number: "+o.getNumber()+", "+"longNumber: "+o.getLongNumber()+", "+"string: "+"\"" + o.getString() + "\""+", "+"active: "+o.isActive() + "}"; 
    }

Nested object example

    public String toJson(net.piotrl.jvm.jsonassist.mock.RecursiveObject o) {
        return "{" + "id: "+o.getId()+", "+"child: "+(o.getChild() != null? new net.piotrl.jvm.jsonassist.generation.Jitson().toJson(o.getChild()): null) + "}"; 
    }

Collection example

    public String toJson(java.util.Collection o) {
        java.util.List objects = new java.util.ArrayList(o.size());
        Object[] array = o.toArray();
        for (int i = 0; i < array.length; i++) {
          objects.add(new net.piotrl.jvm.jsonassist.generation.Jitson().toJson(array[i]));
        }
       return "[" + String.join(", ", objects) + "]"; 
    }