title: spring boot - how to avoid "Failed to instantiate [java.util.List]: Specified class is an interface" in HTTP controller handler?
body: <p>In my spring boot REST API application, I need to handle HTTP POST by accepting a strongly-typed list as my input:</p>
  
  <pre><code>@RestController
  public class CusttableController {
  
      static final Logger LOG = LoggerFactory.getLogger(CusttableController.class);
  
      @RequestMapping(value="/custtable/update", method=RequestMethod.POST)
      @ResponseBody
      public String updateCusttableRecords(List&lt;Custtable&gt; customers) {
          try {
                  for (Custtable cust : customers) {
  
                  Custtable customer = (Custtable) custtableDao.getById(Custtable.class, 
                          new CusttableCompositeKey 
                          (cust.getAccountnum(),cust.getPartition(),cust.getDataareaid()));
  </code></pre>
  
  <p>In the Jersey version of this API, this worked just fine, but with Spring Boot, it gives me this error:</p>
  
  <pre><code>org.springframework.beans.BeanInstantiationException: Failed to instantiate [java.util.List]: Specified class is an interface
  </code></pre>
  
  <p>What is the proper way for me to accept a strongly-typed List in Spring Boot?</p>