I do not know where the contradiction comes from, since you do not include any references.
If you do some detective work and first look at the Web Service Metadata 2.0 (JSR-181) specification document, section 4.1 then you can read that the default value is as defined in section 3.2 in the JAX-WS specification document. Reading this section, there you can see that it is indeed as you say - the target namespace is prefixed by "http://".
If it is critical to your application that the target namespace is defined one or another way, then supply a value and do not rely on a default value.
Can you really tell me that we aren't dealing with suspicious baked goods? And then there is this tiny ad:
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