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java2wsdl uses a compiled Web service endpoint's implementation (SEI) class and associated types classes to generate a WSDL file.
Note: java2wsdl is available only in use for the current production 2.0.x series of CXF. For the upcoming 2.1 versions, please use java2ws instead.
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java2wsdl -o hello.wsdl -t http://cxf.apache.org org.apache.hello_world_soap_http.Greeter
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In CXF we have a Maven plugin, called "cxf-codegen-plugin", which includes a "java2wsdl" goal. You can find more information in Maven Integration and Plugin Using CXF with maven.