Admittedly, XML/SOAP and Web-Services might be old school techniques -- but they are still relevant ...

... thus, easy to operate JAXB and JAX-WS code is also still a reasonable objective to pursue:

Informaticum's Plugins for customised JAXB/JAX-WS Java Code

This project offers some plugins to be used in conjunction with code generation by, e.g., the Apache CXF WSDL-to-Java Plugin.

Code-Reuse Plugin

Some of the generated code is kept private even though it is immutable. For example, there are several QName instances you might be interested in.

This plugin manipulates the access modifier of such code. Just put the plugin into the wsdl2java's classpath and activate by providing the xjc argument -informaticum-xjc-reuse. The plugin parameter(s) are:

• -reuse-qnames: Modify QName constants' accessibility to [public]. Default: false

In case you are using Maven and the CXF plugin, the configuration is:

<plugin>
  <groupId>org.apache.cxf</groupId>
  <artifactId>cxf-codegen-plugin</artifactId>
  <version>${current-cxf-version}</version>
  <dependencies>
    <dependency>
      <groupId>de.informaticum.xjc</groupId>
      <artifactId>xjc-plugins</artifactId>
      <version>${current-project-version}</version>
    </dependency>
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>${current-logback-version}</version>
    </dependency>
    [...]
  </dependencies>
  <executions>
    <execution>
      <id>generate-gematik-api-webservices</id>
      <phase>generate-sources</phase>
      <goals>
        <goal>wsdl2java</goal>
      </goals>
      [...]
      <configuration>
        <defaultOptions>
          <xjcargs>
            <xjcarg>-informaticum-xjc-reuse</xjcarg>
            <xjcarg>-reuse-qnames</xjcarg>
          </xjcargs>
        </defaultOptions>
        [...]
      </configuration>
    </execution>
  </executions>
</plugin>

In result, you will see Code similar to:

package org.w3._2006._05.addressing.wsdl;

import javax.xml.bind.annotation.XmlRegistry;
import javax.xml.namespace.QName;

@XmlRegistry
public class ObjectFactory {

    public final static QName _ServiceName_QNAME = new QName("http://www.w3.org/2006/05/addressing/wsdl", "ServiceName");
    public final static QName _InterfaceName_QNAME = new QName("http://www.w3.org/2006/05/addressing/wsdl", "InterfaceName");

    [...]

Trace Plugin

This plugin traces all generated sources, mainly intended to enable debugging purposes. (For this, the plugin -- likewise all other plugins -- uses SLF4J as the logging API.) Just put the plugin into the wsdl2java's classpath and activate by providing the xjc argument -informaticum-xjc-trace. The plugin parameter(s) are:

• none so far

In case you are using Maven and the CXF plugin, the configuration (exemplarily in combination with logback and a custom logback configuration) is:

<plugin>
  <groupId>org.apache.cxf</groupId>
  <artifactId>cxf-codegen-plugin</artifactId>
  <version>${current-cxf-version}</version>
  <dependencies>
    <dependency>
      <groupId>de.informaticum.xjc</groupId>
      <artifactId>xjc-plugins</artifactId>
      <version>${current-project-version}</version>
    </dependency>
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>${current-logback-version}</version>
    </dependency>
    [...]
  </dependencies>
  <executions>
    <execution>
      <id>generate-gematik-api-webservices</id>
      <phase>generate-sources</phase>
      <goals>
        <goal>wsdl2java</goal>
      </goals>
      [...]
      <configuration>
        <additionalJvmArgs>-Dlogback.configurationFile=${project.basedir}/src/main/cxf/logback-for-cxf-plugin.xml</additionalJvmArgs>
        <defaultOptions>
          <xjcargs>
            <xjcarg>-informaticum-xjc-trace</xjcarg>
          </xjcargs>
        </defaultOptions>
        [...]
      </configuration>
    </execution>
  </executions>
</plugin>

In result, the logging messages will be printed wherever said by the logback configuration.