Properties properties = new Properties(); properties.put("key", 1); // fix bug: such properties can't be serialized

[fan2008shuai]

Properties properties = new Properties();
properties.put("key", 1);
fix bug: such properties can't be serialized

[cowtowncoder]

Hmmh. This is tricky.

So, I can see that if you use Properties as just general Map<String, String> -- which to me is wrong, even tho JDK sort of allows it (due to raw typing of its extension) -- there is problem with serialization.

Unfortunately existing handling is absolutely required to make deserialization (reading json as Properties) work correctly, and making suggested change actually breaks 3 existing unit tests (earlier #810 lead to type parameters being derived to make Properties look like Map<String, String>, to avoid quietly dropping non-String values).

Given this, I don't think change as suggested can be used. But I will file an issue for the problem itself -- it seems reasonable that serialization of Properties with non-String values should not fail with an exception but work similar to Map<String, Object>.

[cowtowncoder]

Created #2657 as follow-up.