How to convert a Java object (bean) to key-value pairs (and vice versa)?

Solution 1:

Lots of potential solutions, but let's add just one more. Use Jackson (JSON processing lib) to do "json-less" conversion, like:

ObjectMapper m = new ObjectMapper();
Map<String,Object> props = m.convertValue(myBean, Map.class);
MyBean anotherBean = m.convertValue(props, MyBean.class);

(this blog entry has some more examples)

You can basically convert any compatible types: compatible meaning that if you did convert from type to JSON, and from that JSON to result type, entries would match (if configured properly can also just ignore unrecognized ones).

Works well for cases one would expect, including Maps, Lists, arrays, primitives, bean-like POJOs.

Solution 2:

There is always apache commons beanutils but of course it uses reflection under the hood