java - 存在可选的长参数，但不能转换为空值

Question

您好，我正在 Web 上进行开发，所以我有一个 ajax 函数，该函数调用一个 Controller 函数，该 Controller 函数又调用一个 DAO 函数(以对 DB 进行更改)。我在 Controller 函数中遇到了上面的异常..

Controller 函数:

@RequestMapping(value="/changeIsPublic", method=RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
public  @ResponseBody boolean changeIsPublic(HttpServletRequest request, Locale locale, Model model, long transactionId, boolean isPublic) {
    boolean result = false; 
    try {
            boxDao.changeIsPublicStatus(transactionId, isPublic);
            result = true;

        } catch (Exception e) {
            logger.debug("Failed to publish transaction. transaction ID: " + transactionId + e.getMessage());
        }
        return result;
}

DAO 函数:

public Box changeIsPublicStatus(long id, boolean isPublic) {
    Criteria criteria = getCurrentSession().createCriteria(Box.class);
    criteria.add(Restrictions.eq("id", id));
    Box transaction = (Box) criteria.uniqueResult();
    transaction.setIsPublic(isPublic);
    return transaction;
}

异常(exception):

    SEVERE: Servlet.service() for servlet [appServlet] in context with path [/goblin] threw exception [Request processing failed; nested exception is java.lang.IllegalStateException: Optional long parameter 'transactionId' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type.] with root cause
java.lang.IllegalStateException: Optional long parameter 'transactionId' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type.
    at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.handleNullValue(AbstractNamedValueMethodArgumentResolver.java:188)
    at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:94)
    at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:77)
    at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:162)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:123)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:827)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.orm.hibernate4.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:149)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at com.yes.java.security.AuthenticationFilter.doFilter(AuthenticationFilter.java:105)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)    `

Answer 1

我在使用 Jackson REST Web 服务(RESTful Spring Controller )时遇到此错误。问题是我忘记了 @PathVariable 注释，它告诉 Web 服务它应该在哪里接收您的输入以生成响应，所以它不知道我应该将我的输入传递到哪里。我的修复是:

@RequestMapping(value = "/supplier/{supplierId}")
public List<PurchaseInvoice> getPurchaseInvoicesBySupplierId(@PathVariable int supplierId) {
    return purchaseInvoiceService.getPurchaseInvoicesBySupplierId(supplierId);
}