如何在spring boot中从我的请求对象创建正确的请求参数？

Question

我想在spring boot中从ajax request.but中获取请求参数对象，我可以获得一个error.How来生成正确的ajax参数？

这是Spring Boot 2中的一个问题

这是我的请求对象定义：

import lombok.Data;

@Data
public class PageReq<T> {

    private Integer pageIndex;
    private Integer pageSize;
    private T whereObj;

    private String sortAttr;
    private String sortDirect;
}

这是我的restcontroller代码：

 @GetMapping("/getbypage2")
    public PageUtils getByPage2(PageReq<Student> req) {

        Sort sort = new Sort(Sort.Direction.DESC, "id");

        Pageable pageable = PageRequest.of(req.getPageIndex(),
                req.getPageSize()
                , sort);

        Student student=req.getWhereObj();


...

我的ajax代码是这样的：

 $.ajax({
            url: '/webapi/student/getbypage2'
            ,data:{
              pageIndex:0,
              pageSize:5,
                whereObj:{name:'abc'}




            }

        }).done(function (rs) {

...

我想在springboot.but中获取请求对象，我得到了一个错误：

/*
* 提示：该行代码过长，系统自动注释不进行高亮。一键复制会移除系统注释 
* {"timestamp":"2019-05-24T16:27:50.429+0000","status":500,"error":"Internal Server Error","message":"Invalid property 'whereObj[0][name]' of bean class [cn.edu.ctbu.labtest.core.PageReq]: Illegal attempt to get property 'whereObj' threw exception; nested exception is org.springframework.beans.InvalidPropertyException: Invalid property 'whereObj[0][name]' of bean class [cn.edu.ctbu.labtest.core.PageReq]: Property referenced in indexed property path 'whereObj[0][name]' is neither an array nor a List nor a Set nor a Map; returned value was [java.lang.Object@5fbe1b9e]","trace":"org.springframework.beans.InvalidPropertyException: Invalid property 'whereObj[0][name]' of bean class [cn.edu.ctbu.labtest.core.PageReq]: Illegal attempt to get property 'whereObj' threw exception; nested exception is org.springframework.beans.InvalidPropertyException: Invalid property 'whereObj[0][name]' of bean class [cn.edu.ctbu.labtest.core.PageReq]: Property referenced in indexed property path 'whereObj[0][name]' is neither an array nor a List nor a Set nor a Map; returned value was [java.lang.Object@5fbe1b9e]\r\n\tat org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue(AbstractNestablePropertyAccessor.java:707)\r\n\tat org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyHoldingValue(AbstractNestablePropertyAccessor.java:391)\r\n\tat org.springframework.beans.AbstractNestablePropertyAccessor.processKeyedProperty(AbstractNestablePropertyAccessor.java:284)\r\n\tat org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:275)\r\n\tat org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:266)\r\n\tat org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:97)\r\n\tat org.springframework.validation.DataBinder.applyPropertyValues(DataBinder.java:848)\r\n\tat org.springframework.validation.DataBinder.doBind(DataBinder.java:744)\r\n\tat org.springframework.web.bind.WebDataBinder.doBind(WebDataBinder.java:197)\r\n\tat org.springframework.web.bind.ServletRequestDataBinder.bind(ServletRequestDataBinder.java:107)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor.bindRequestParameters(ServletModelAttributeMethodProcessor.java:157)\r\n\tat org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:160)\r\n\tat org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:126)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:166)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:892)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797)\r\n\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)\r\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)\r\n\tat org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:634)\r\n\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:741)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:200)\r\n\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)\r\n\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)\r\n\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)\r\n\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)\r\n\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)\r\n\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)\r\n\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)\r\n\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)\r\n\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:834)\r\n\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415)\r\n\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)\r\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)\r\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)\r\n\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)\r\n\tat java.lang.Thread.run(Thread.java:748)\r\nCaused by: org.springframework.beans.InvalidPropertyException: Invalid property 'whereObj[0][name]' of bean class [cn.edu.ctbu.labtest.core.PageReq]: Property referenced in indexed property path 'whereObj[0][name]' is neither an array nor a List nor a Set nor a Map; returned value was [java.lang.Object@5fbe1b9e]\r\n\tat org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue(AbstractNestablePropertyAccessor.java:685)\r\n\t... 62 more\r\n","path":"/webapi/student/getbypage2"}
*/

那么，如何解决这个问题呢？

我需要你的帮助！谢谢！

Answer 1

您可以使用Spring：use pageable in controller提供的可分页

示例：

@RestController
class StudentController {
 
 private StudentRepo repo; // autowire repo via constructor injection
 
 ....

 @GetMapping("/students")
 public Page<Student> loadStudents(Model model, Pageable pageable) {
    return repo.findAll(pageable);
 }

你让你打电话就像

url : '/students?page=1&size=25&sort=lastname,asc'

可分页实例的

请求参数求值

页面：要检索的页面。0 -已索引，默认为0。

Size ：要检索的页面的大小。默认为20。

sort：按属性，属性(，ASC|DESC)格式排序的属性。默认排序方向为升序。如果要切换方向，请使用多个排序参数，例如，?sort=firstname&sort=lastname，asc.， -