做Webservice时报错java.util.List是接口, 而 JAXB 无法处理接口。

Caused by: com.sun.xml.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions
java.util.List是接口, 而 JAXB 无法处理接口。
this problem is related to the following location:
at java.util.List

at com.sun.xml.bind.v2.runtime.IllegalAnnotationsException$Builder.check(IllegalAnnotationsException.java:106)
at com.sun.xml.bind.v2.runtime.JAXBContextImpl.getTypeInfoSet(JAXBContextImpl.java:471)
at com.sun.xml.bind.v2.runtime.JAXBContextImpl.<init>(JAXBContextImpl.java:303)
at com.sun.xml.bind.v2.runtime.JAXBContextImpl.<init>(JAXBContextImpl.java:139)
at com.sun.xml.bind.v2.runtime.JAXBContextImpl$JAXBContextBuilder.build(JAXBContextImpl.java:1156)
at com.sun.xml.bind.v2.ContextFactory.createContext(ContextFactory.java:165)
at com.sun.xml.bind.api.JAXBRIContext.newInstance(JAXBRIContext.java:167)
at com.sun.xml.bind.api.JAXBRIContext.newInstance(JAXBRIContext.java:111)
at com.sun.xml.ws.developer.JAXBContextFactory$1.createJAXBContext(JAXBContextFactory.java:113)
at com.sun.xml.ws.db.glassfish.JAXBRIContextFactory.newContext(JAXBRIContextFactory.java:94)
... 73 more

 counts of IllegalAnnotationExceptions and JAXB can't handle interfaces

大致意思就是说返回值类型不能是接口类型。

解决方法：将服务端的services接口返回的Map类型的值，改成HashMap.
结论：在做webServices复杂类型值传递时，返回值的类型不要用接口类型。例如(List应该改为ArrayList,Map改为HashMap等)