Java Spring MVC web应用程序:未找到默认构造函数
项目邮编:Java Spring MVC web应用程序:未找到默认构造函数,java,spring,spring-mvc,Java,Spring,Spring Mvc,项目邮编: 由于HTTP状态为500错误,无法执行Spring web app。它还指出,没有为DSLR找到默认构造函数,但实际上有一个默认构造函数。也许这与应用程序上下文或我的bean声明的方式有关?我的应用程序无法启动的原因是什么 DSLR: package main.java.com.springapp.mvc.model; public class DSLR { public DSLR() { } public void init() {}
由于HTTP状态为500错误,无法执行Spring web app。它还指出,没有为DSLR找到默认构造函数,但实际上有一个默认构造函数。也许这与应用程序上下文或我的bean声明的方式有关?我的应用程序无法启动的原因是什么 DSLR:
package main.java.com.springapp.mvc.model;
public class DSLR {
public DSLR() {
}
public void init() {}
private int dslrId;
private String model;
private int price;
private String description;
public int getDslrId() {
return dslrId;
}
public void setDslrId(int dslrId) {
this.dslrId = dslrId;
}
public String getModel() {
return model;
}
public void setModel(String model) {
this.model = model;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
@Override
public String toString() {
return "DSLR [dslr=" + dslrId + ", model=" + model
+ ", price=" + price+ ", description=" + description+"]";
}
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/" />
<property name="suffix" value=".jsp" />
</bean>
<bean name="s" class="main.java.com.springapp.mvc.controller.DSLRServletController">
<property name="dslrDAO" ref="dslrDAO" />
<property name="DSLR" ref="DSLR" />
</bean>
<bean id="dslrDAO" class="main.java.com.springapp.mvc.dao.DSLRDAO">
</bean>
<bean id="DSLR" class="main.java.com.springapp.mvc.model.DSLR">
</bean>
</beans>
HTTP Status 500 - Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
type Exception report
message Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:927)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:108)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:770)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:363)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:439)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:427)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
java.lang.Class.getConstructor0(Class.java:2810)
java.lang.Class.getDeclaredConstructor(Class.java:2053)
org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:105)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:770)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:363)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:439)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:427)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.52 logs.
package main.java.com.springapp.mvc.controller;
import main.java.com.springapp.mvc.dao.DSLRDAO;
import main.java.com.springapp.mvc.model.DSLR;
import main.java.com.springapp.mvc.pckg.DSLRForm;
import main.java.com.springapp.mvc.pckg.DSLRValidaor;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.Serializable;
import java.util.*;
@Controller
public class DSLRServletController extends HttpServlet {
static Logger logger = Logger.getLogger(DSLRServletController.class);
private DSLR DSLR;
private DSLRDAO dslrDAO;
private DSLR dslr;
/* request.setCharacterEncoding("UTF-8");
response.setContentType("text/html; charset=utf-8");
List list = getActions(request, response);
response.setContentType("text/html; charset=UTF-8");*/
//@Autowired ???
public DSLRServletController() {
this.dslrDAO = new DSLRDAO();
}
public void init() {logger.error("DSLRServlet.init(): just started"); }
/*
/s GET
/s?id=1 GET
/s?action=save POST
/dslrservice?id=1&tm=<timestamp> GET
*/
@RequestMapping(value = "/s", method = RequestMethod.GET)
public String showHTMLResponse(@ModelAttribute("dslrs") DSLR dslrs[],
@ModelAttribute("dslr") DSLR dslr,
@ModelAttribute("dslrErrors") HashMap dslrErrors,
@ModelAttribute ("dslrform") DSLRForm dslrForm,
@RequestParam("id") String paramId,
@RequestParam("action") String paramAction,
Model model){
if(paramId == null || paramId.equals("")){
//show_all_dslrs
dslrs = getAllDslrs(); // DSLR adslrs[] -> to MODEL;
return "dslrs";
}else{
//show_this_dslr;
HashMap<String,Object> dslrHashMap = getDSLRById(paramId);
dslr = (DSLR) dslrHashMap.get("dslr");
dslrForm = (DSLRForm)dslrHashMap.get("dslrForm");
dslrErrors = (HashMap)dslrHashMap.get("dslrErrors");
if(dslr != null){
// getServletConfig().getServletContext().getRequestDispatcher("/dslr.jsp").forward(request, response);
return "dslr";
}
else{
return "error";
}
}
}
@RequestMapping(value = "/s", method = RequestMethod.POST)
public String showHTMLResponsePOST(@ModelAttribute("dslrs") DSLR dslrs[],
@ModelAttribute("dslrErrors") HashMap<?,?> dslrErrors,
@ModelAttribute ("dslrform") DSLRForm dslrForm,
@RequestParam("id") String paramId,
@RequestParam("action") String paramAction,
@RequestParam("dslr_model") String paramModel,
@RequestParam("price") String paramPrice,
@RequestParam("description") String paramDescription,
Model model){
int iStatusCode = 0;
if(paramAction.equals("save") )
iStatusCode = saveDSLR(paramId, paramModel, paramPrice, paramDescription, dslrErrors, dslrForm); // POST
return "dslrs";
}
private int saveDSLR(String paramId,
String paramModel,
String paramPrice,
String paramDescription,
HashMap<?,?> context_dslrErrors,
DSLRForm context_dslrForm
) {
int byte0 = 1;
try {
DSLRValidaor dslrValidaor = new DSLRValidaor();
DSLRForm dslrForm = new DSLRForm();
dslrForm.setDslrId(paramId);
dslrForm.setModel(paramModel);
dslrForm.setPrice(paramPrice);
dslrForm.setDescription(paramDescription);
HashMap hashmap = dslrValidaor.Validate(dslrForm);
if(hashmap.size() > 0) {
context_dslrForm = dslrForm;
context_dslrErrors = hashmap;
byte0 = -1;
} else{
DSLRDAO planedao = new DSLRDAO();
DSLR dslr = new DSLR();
dslr.setDslrId(Integer.parseInt(paramId));
dslr.setModel(paramModel);
dslr.setPrice(Integer.parseInt(paramPrice));
dslr.setDescription(paramDescription);
planedao.update(dslr);
}
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("DSLRServlet.saveDSLR():").append(exception.getMessage()).toString());
byte0 = -1;
}
return byte0;
}
private DSLR[] getAllDslrs(){
DSLR adslrs[] = null;
try
{
DSLRDAO DSLRDAO = new DSLRDAO();
adslrs = (DSLR[])DSLRDAO.findAll();
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("PlaneServlet.getAllPlanes():").append(exception.getMessage()).toString());
}
// request.setAttribute("dslrs", adslrs);
return adslrs;
}
private HashMap<String, Object> getDSLRById(String s)
{
HashMap<String,Object> map = new HashMap<String, Object>();
DSLR dslr = null;
try {
int i = Integer.parseInt(s);
DSLRDAO DSLRDAO = new DSLRDAO();
dslr = (DSLR)DSLRDAO.findById(i);
DSLRForm dslrForm = new DSLRForm();
dslrForm.setDslrId(Integer.toString(dslr.getDslrId()));
dslrForm.setModel(dslr.getModel());
dslrForm.setPrice(Integer.toString(dslr.getPrice()));
dslrForm.setDescription(dslr.getDescription());
map.put("dslr", dslr);
map.put("dslrform", dslrForm);
map.put("dslrErrors", new HashMap());
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("DSLRServlet.getDSLRById():").append(exception.getMessage()).toString());
}
return map;
}
public void setDslrDAO(DSLRDAO dslrDAO) {
this.dslrDAO = dslrDAO;
}
public DSLRDAO getDslrDAO() {
return dslrDAO;
}
public void setDSLR(main.java.com.springapp.mvc.model.DSLR DSLR) {
dslr = DSLR;
}
public main.java.com.springapp.mvc.model.DSLR getDSLR() {
return dslr;
}
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/"/>
<property name="suffix" value=".jsp"/>
</bean>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/" />
<property name="suffix" value=".jsp" />
</bean>
</beans>
@Autowired
public DSLRServletController() {
this.dslrDAO = new DSLRDAO();
}
exception
javax.servlet.ServletException: Servlet.init() for servlet mvc-dispatcher threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
java.lang.Thread.run(Thread.java:744)
root cause
java.lang.IllegalStateException: Autowired annotation requires at least one argument: public main.java.com.springapp.mvc.controller.DSLRServletController()
org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:243)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:976)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:949)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:490)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461)
org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:607)
org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:647)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:598)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:661)
org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:517)
org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:458)
org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:138)
javax.servlet.GenericServlet.init(GenericServlet.java:158)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
java.lang.Thread.run(Thread.java:744)
web.xml
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>Spring MVC Application</display-name>
<servlet>
<servlet-name>mvc-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>mvc-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc"/>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/"/>
<property name="suffix" value=".jsp"/>
</bean>
</beans>
错误:
package main.java.com.springapp.mvc.model;
public class DSLR {
public DSLR() {
}
public void init() {}
private int dslrId;
private String model;
private int price;
private String description;
public int getDslrId() {
return dslrId;
}
public void setDslrId(int dslrId) {
this.dslrId = dslrId;
}
public String getModel() {
return model;
}
public void setModel(String model) {
this.model = model;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
@Override
public String toString() {
return "DSLR [dslr=" + dslrId + ", model=" + model
+ ", price=" + price+ ", description=" + description+"]";
}
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/" />
<property name="suffix" value=".jsp" />
</bean>
<bean name="s" class="main.java.com.springapp.mvc.controller.DSLRServletController">
<property name="dslrDAO" ref="dslrDAO" />
<property name="DSLR" ref="DSLR" />
</bean>
<bean id="dslrDAO" class="main.java.com.springapp.mvc.dao.DSLRDAO">
</bean>
<bean id="DSLR" class="main.java.com.springapp.mvc.model.DSLR">
</bean>
</beans>
HTTP Status 500 - Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
type Exception report
message Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:927)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:108)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:770)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:363)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:439)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:427)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
java.lang.Class.getConstructor0(Class.java:2810)
java.lang.Class.getDeclaredConstructor(Class.java:2053)
org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:105)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:770)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:363)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:439)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:427)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.52 logs.
package main.java.com.springapp.mvc.controller;
import main.java.com.springapp.mvc.dao.DSLRDAO;
import main.java.com.springapp.mvc.model.DSLR;
import main.java.com.springapp.mvc.pckg.DSLRForm;
import main.java.com.springapp.mvc.pckg.DSLRValidaor;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.Serializable;
import java.util.*;
@Controller
public class DSLRServletController extends HttpServlet {
static Logger logger = Logger.getLogger(DSLRServletController.class);
private DSLR DSLR;
private DSLRDAO dslrDAO;
private DSLR dslr;
/* request.setCharacterEncoding("UTF-8");
response.setContentType("text/html; charset=utf-8");
List list = getActions(request, response);
response.setContentType("text/html; charset=UTF-8");*/
//@Autowired ???
public DSLRServletController() {
this.dslrDAO = new DSLRDAO();
}
public void init() {logger.error("DSLRServlet.init(): just started"); }
/*
/s GET
/s?id=1 GET
/s?action=save POST
/dslrservice?id=1&tm=<timestamp> GET
*/
@RequestMapping(value = "/s", method = RequestMethod.GET)
public String showHTMLResponse(@ModelAttribute("dslrs") DSLR dslrs[],
@ModelAttribute("dslr") DSLR dslr,
@ModelAttribute("dslrErrors") HashMap dslrErrors,
@ModelAttribute ("dslrform") DSLRForm dslrForm,
@RequestParam("id") String paramId,
@RequestParam("action") String paramAction,
Model model){
if(paramId == null || paramId.equals("")){
//show_all_dslrs
dslrs = getAllDslrs(); // DSLR adslrs[] -> to MODEL;
return "dslrs";
}else{
//show_this_dslr;
HashMap<String,Object> dslrHashMap = getDSLRById(paramId);
dslr = (DSLR) dslrHashMap.get("dslr");
dslrForm = (DSLRForm)dslrHashMap.get("dslrForm");
dslrErrors = (HashMap)dslrHashMap.get("dslrErrors");
if(dslr != null){
// getServletConfig().getServletContext().getRequestDispatcher("/dslr.jsp").forward(request, response);
return "dslr";
}
else{
return "error";
}
}
}
@RequestMapping(value = "/s", method = RequestMethod.POST)
public String showHTMLResponsePOST(@ModelAttribute("dslrs") DSLR dslrs[],
@ModelAttribute("dslrErrors") HashMap<?,?> dslrErrors,
@ModelAttribute ("dslrform") DSLRForm dslrForm,
@RequestParam("id") String paramId,
@RequestParam("action") String paramAction,
@RequestParam("dslr_model") String paramModel,
@RequestParam("price") String paramPrice,
@RequestParam("description") String paramDescription,
Model model){
int iStatusCode = 0;
if(paramAction.equals("save") )
iStatusCode = saveDSLR(paramId, paramModel, paramPrice, paramDescription, dslrErrors, dslrForm); // POST
return "dslrs";
}
private int saveDSLR(String paramId,
String paramModel,
String paramPrice,
String paramDescription,
HashMap<?,?> context_dslrErrors,
DSLRForm context_dslrForm
) {
int byte0 = 1;
try {
DSLRValidaor dslrValidaor = new DSLRValidaor();
DSLRForm dslrForm = new DSLRForm();
dslrForm.setDslrId(paramId);
dslrForm.setModel(paramModel);
dslrForm.setPrice(paramPrice);
dslrForm.setDescription(paramDescription);
HashMap hashmap = dslrValidaor.Validate(dslrForm);
if(hashmap.size() > 0) {
context_dslrForm = dslrForm;
context_dslrErrors = hashmap;
byte0 = -1;
} else{
DSLRDAO planedao = new DSLRDAO();
DSLR dslr = new DSLR();
dslr.setDslrId(Integer.parseInt(paramId));
dslr.setModel(paramModel);
dslr.setPrice(Integer.parseInt(paramPrice));
dslr.setDescription(paramDescription);
planedao.update(dslr);
}
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("DSLRServlet.saveDSLR():").append(exception.getMessage()).toString());
byte0 = -1;
}
return byte0;
}
private DSLR[] getAllDslrs(){
DSLR adslrs[] = null;
try
{
DSLRDAO DSLRDAO = new DSLRDAO();
adslrs = (DSLR[])DSLRDAO.findAll();
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("PlaneServlet.getAllPlanes():").append(exception.getMessage()).toString());
}
// request.setAttribute("dslrs", adslrs);
return adslrs;
}
private HashMap<String, Object> getDSLRById(String s)
{
HashMap<String,Object> map = new HashMap<String, Object>();
DSLR dslr = null;
try {
int i = Integer.parseInt(s);
DSLRDAO DSLRDAO = new DSLRDAO();
dslr = (DSLR)DSLRDAO.findById(i);
DSLRForm dslrForm = new DSLRForm();
dslrForm.setDslrId(Integer.toString(dslr.getDslrId()));
dslrForm.setModel(dslr.getModel());
dslrForm.setPrice(Integer.toString(dslr.getPrice()));
dslrForm.setDescription(dslr.getDescription());
map.put("dslr", dslr);
map.put("dslrform", dslrForm);
map.put("dslrErrors", new HashMap());
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("DSLRServlet.getDSLRById():").append(exception.getMessage()).toString());
}
return map;
}
public void setDslrDAO(DSLRDAO dslrDAO) {
this.dslrDAO = dslrDAO;
}
public DSLRDAO getDslrDAO() {
return dslrDAO;
}
public void setDSLR(main.java.com.springapp.mvc.model.DSLR DSLR) {
dslr = DSLR;
}
public main.java.com.springapp.mvc.model.DSLR getDSLR() {
return dslr;
}
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/"/>
<property name="suffix" value=".jsp"/>
</bean>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/" />
<property name="suffix" value=".jsp" />
</bean>
</beans>
@Autowired
public DSLRServletController() {
this.dslrDAO = new DSLRDAO();
}
exception
javax.servlet.ServletException: Servlet.init() for servlet mvc-dispatcher threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
java.lang.Thread.run(Thread.java:744)
root cause
java.lang.IllegalStateException: Autowired annotation requires at least one argument: public main.java.com.springapp.mvc.controller.DSLRServletController()
org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:243)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:976)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:949)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:490)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461)
org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:607)
org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:647)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:598)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:661)
org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:517)
org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:458)
org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:138)
javax.servlet.GenericServlet.init(GenericServlet.java:158)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
java.lang.Thread.run(Thread.java:744)
由于某种原因,出现了2个错误。要正确设置项目,应更改哪些内容?
更新3 新的mvc dispatcher servlet.xml:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/"/>
<property name="suffix" value=".jsp"/>
</bean>
<bean id="DSLR" class="main.java.com.springapp.mvc.model.DSLR" />
</beans>
更新4:
package main.java.com.springapp.mvc.model;
public class DSLR {
public DSLR() {
}
public void init() {}
private int dslrId;
private String model;
private int price;
private String description;
public int getDslrId() {
return dslrId;
}
public void setDslrId(int dslrId) {
this.dslrId = dslrId;
}
public String getModel() {
return model;
}
public void setModel(String model) {
this.model = model;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
@Override
public String toString() {
return "DSLR [dslr=" + dslrId + ", model=" + model
+ ", price=" + price+ ", description=" + description+"]";
}
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/" />
<property name="suffix" value=".jsp" />
</bean>
<bean name="s" class="main.java.com.springapp.mvc.controller.DSLRServletController">
<property name="dslrDAO" ref="dslrDAO" />
<property name="DSLR" ref="DSLR" />
</bean>
<bean id="dslrDAO" class="main.java.com.springapp.mvc.dao.DSLRDAO">
</bean>
<bean id="DSLR" class="main.java.com.springapp.mvc.model.DSLR">
</bean>
</beans>
HTTP Status 500 - Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
type Exception report
message Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:927)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [[Lmain.java.com.springapp.mvc.model.DSLR;]: No default constructor found; nested exception is java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:108)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:770)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:363)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:439)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:427)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
java.lang.Class.getConstructor0(Class.java:2810)
java.lang.Class.getDeclaredConstructor(Class.java:2053)
org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:105)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:770)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:363)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:439)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:427)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.52 logs.
package main.java.com.springapp.mvc.controller;
import main.java.com.springapp.mvc.dao.DSLRDAO;
import main.java.com.springapp.mvc.model.DSLR;
import main.java.com.springapp.mvc.pckg.DSLRForm;
import main.java.com.springapp.mvc.pckg.DSLRValidaor;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.Serializable;
import java.util.*;
@Controller
public class DSLRServletController extends HttpServlet {
static Logger logger = Logger.getLogger(DSLRServletController.class);
private DSLR DSLR;
private DSLRDAO dslrDAO;
private DSLR dslr;
/* request.setCharacterEncoding("UTF-8");
response.setContentType("text/html; charset=utf-8");
List list = getActions(request, response);
response.setContentType("text/html; charset=UTF-8");*/
//@Autowired ???
public DSLRServletController() {
this.dslrDAO = new DSLRDAO();
}
public void init() {logger.error("DSLRServlet.init(): just started"); }
/*
/s GET
/s?id=1 GET
/s?action=save POST
/dslrservice?id=1&tm=<timestamp> GET
*/
@RequestMapping(value = "/s", method = RequestMethod.GET)
public String showHTMLResponse(@ModelAttribute("dslrs") DSLR dslrs[],
@ModelAttribute("dslr") DSLR dslr,
@ModelAttribute("dslrErrors") HashMap dslrErrors,
@ModelAttribute ("dslrform") DSLRForm dslrForm,
@RequestParam("id") String paramId,
@RequestParam("action") String paramAction,
Model model){
if(paramId == null || paramId.equals("")){
//show_all_dslrs
dslrs = getAllDslrs(); // DSLR adslrs[] -> to MODEL;
return "dslrs";
}else{
//show_this_dslr;
HashMap<String,Object> dslrHashMap = getDSLRById(paramId);
dslr = (DSLR) dslrHashMap.get("dslr");
dslrForm = (DSLRForm)dslrHashMap.get("dslrForm");
dslrErrors = (HashMap)dslrHashMap.get("dslrErrors");
if(dslr != null){
// getServletConfig().getServletContext().getRequestDispatcher("/dslr.jsp").forward(request, response);
return "dslr";
}
else{
return "error";
}
}
}
@RequestMapping(value = "/s", method = RequestMethod.POST)
public String showHTMLResponsePOST(@ModelAttribute("dslrs") DSLR dslrs[],
@ModelAttribute("dslrErrors") HashMap<?,?> dslrErrors,
@ModelAttribute ("dslrform") DSLRForm dslrForm,
@RequestParam("id") String paramId,
@RequestParam("action") String paramAction,
@RequestParam("dslr_model") String paramModel,
@RequestParam("price") String paramPrice,
@RequestParam("description") String paramDescription,
Model model){
int iStatusCode = 0;
if(paramAction.equals("save") )
iStatusCode = saveDSLR(paramId, paramModel, paramPrice, paramDescription, dslrErrors, dslrForm); // POST
return "dslrs";
}
private int saveDSLR(String paramId,
String paramModel,
String paramPrice,
String paramDescription,
HashMap<?,?> context_dslrErrors,
DSLRForm context_dslrForm
) {
int byte0 = 1;
try {
DSLRValidaor dslrValidaor = new DSLRValidaor();
DSLRForm dslrForm = new DSLRForm();
dslrForm.setDslrId(paramId);
dslrForm.setModel(paramModel);
dslrForm.setPrice(paramPrice);
dslrForm.setDescription(paramDescription);
HashMap hashmap = dslrValidaor.Validate(dslrForm);
if(hashmap.size() > 0) {
context_dslrForm = dslrForm;
context_dslrErrors = hashmap;
byte0 = -1;
} else{
DSLRDAO planedao = new DSLRDAO();
DSLR dslr = new DSLR();
dslr.setDslrId(Integer.parseInt(paramId));
dslr.setModel(paramModel);
dslr.setPrice(Integer.parseInt(paramPrice));
dslr.setDescription(paramDescription);
planedao.update(dslr);
}
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("DSLRServlet.saveDSLR():").append(exception.getMessage()).toString());
byte0 = -1;
}
return byte0;
}
private DSLR[] getAllDslrs(){
DSLR adslrs[] = null;
try
{
DSLRDAO DSLRDAO = new DSLRDAO();
adslrs = (DSLR[])DSLRDAO.findAll();
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("PlaneServlet.getAllPlanes():").append(exception.getMessage()).toString());
}
// request.setAttribute("dslrs", adslrs);
return adslrs;
}
private HashMap<String, Object> getDSLRById(String s)
{
HashMap<String,Object> map = new HashMap<String, Object>();
DSLR dslr = null;
try {
int i = Integer.parseInt(s);
DSLRDAO DSLRDAO = new DSLRDAO();
dslr = (DSLR)DSLRDAO.findById(i);
DSLRForm dslrForm = new DSLRForm();
dslrForm.setDslrId(Integer.toString(dslr.getDslrId()));
dslrForm.setModel(dslr.getModel());
dslrForm.setPrice(Integer.toString(dslr.getPrice()));
dslrForm.setDescription(dslr.getDescription());
map.put("dslr", dslr);
map.put("dslrform", dslrForm);
map.put("dslrErrors", new HashMap());
}
catch(Exception exception)
{
logger.error((new StringBuilder()).append("DSLRServlet.getDSLRById():").append(exception.getMessage()).toString());
}
return map;
}
public void setDslrDAO(DSLRDAO dslrDAO) {
this.dslrDAO = dslrDAO;
}
public DSLRDAO getDslrDAO() {
return dslrDAO;
}
public void setDSLR(main.java.com.springapp.mvc.model.DSLR DSLR) {
dslr = DSLR;
}
public main.java.com.springapp.mvc.model.DSLR getDSLR() {
return dslr;
}
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="main.java.com.springapp.mvc" >
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/"/>
<property name="suffix" value=".jsp"/>
</bean>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/" />
<property name="suffix" value=".jsp" />
</bean>
</beans>
@Autowired
public DSLRServletController() {
this.dslrDAO = new DSLRDAO();
}
exception
javax.servlet.ServletException: Servlet.init() for servlet mvc-dispatcher threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
java.lang.Thread.run(Thread.java:744)
root cause
java.lang.IllegalStateException: Autowired annotation requires at least one argument: public main.java.com.springapp.mvc.controller.DSLRServletController()
org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.determineCandidateConstructors(AutowiredAnnotationBeanPostProcessor.java:243)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineConstructorsFromBeanPostProcessors(AbstractAutowireCapableBeanFactory.java:976)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:949)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:490)
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461)
org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:607)
org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:647)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:598)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:661)
org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:517)
org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:458)
org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:138)
javax.servlet.GenericServlet.init(GenericServlet.java:158)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
java.lang.Thread.run(Thread.java:744)
回到原始错误:无法实例化bean类[[Lmain.java.com.springapp.mvc.model.DSLR;]
我很困惑。怎么了?我注意到有点冗余。它本身不应该导致这些问题,但可能值得探讨: 您使用
,这似乎是为了加载您的@Controller
-注释的DSLRServletController
。如果是这种情况,则无需在XML配置中声明名为s
的bean。您只需将@Autowired
放在bean属性设置器上。或者,您可以从XML配置中删除
,并相信控制器的增量足够
此外,尽管它可能不相关。如果您使用@Controller
和类路径注释扫描加载某些内容,则根本不需要实现HttpServlet
。@Controller
和Spring MVC的目的是使您的控制器可以是普通的旧Java对象(POJO)
最重要的是,您的
web.xml
看起来只是导致加载mvc dispatcher servlet.xml
(使用servlet名称作为提示),并且没有任何内容正在加载DSLRServletController servlet.xml
。这样做的结果是,
导致加载控制器,但没有设置控制器的任何属性。要进一步清理系统,请将DSLRServletController servlet.xml
移动到mvc dispatcher servlet.xml
,以便您的spring上下文是从单个配置中配置的。如果DSLR
没有默认构造函数,则会收到错误消息:
java.lang.NoSuchMethodException: main.java.com.springapp.mvc.model.DSLR.<init>()
java.lang.NoSuchMethodException:main.java.com.springapp.mvc.model.DSLR.()
现在将其与错误消息进行比较:
java.lang.NoSuchMethodException: [Lmain.java.com.springapp.mvc.model.DSLR;.<init>()
java.lang.NoSuchMethodException:[Lmain.java.com.springapp.mvc.model.DSLR;()
你注意到区别了吗?
[L
?该错误意味着您无法使用构造函数实例化数组,因为数组没有构造函数。这就是为什么您不能将数组用作控制器方法的参数。至少不是这样。使用集合就可以了。在控制器方法中,您使用了如下所示的参数作为数组
@ModelAttribute("dslrs") DSLR dslrs[]
因此,请使用类似于列表的集合
@ModelAttribute("dslrs") ArrayList<DSLR> dslrs
@ModelAttribute(“DSLR”)阵列列表DSLR
我在使用ApacheTomcat 9.0运行Spring boot应用程序时遇到了同样的问题。
现在,我已经解决了这个问题
@RequestMapping("/userhome")
public String userhome(Model model) {
System.out.println("inside bck...");
//List<String> colorList = colorList();`enter code here`
//model.addAttribute("theme", colorList);
//model.addAttribute("home", new UserHome());
return "userhomePage";
}
@RequestMapping(“/userhome”)
公共字符串userhome(模型){
System.out.println(“内部bck…”);
//List colorList=colorList();`在此处输入代码`
//model.addAttribute(“主题”,颜色列表);
//addAttribute(“home”,newuserhome());
返回“用户主页”;
}
在我的例子中,问题不是没有默认构造函数。问题是在rest post调用中传递给控制器的json DTO字段没有设置器。类
DSLR
如何实现可序列化
?我不知道,很可能没有。它没有,我也不明白为什么它会实现ld.您的构建似乎有点混乱。前面的main.java
使它看起来像是一个Maven目录结构,但试图在Ant(或没有m2e的Eclipse)下构建,这会导致各种问题。java不是C!DSLR DSLR[]是C风格。使用java风格的DSLR[]DSLRAS您建议我将2个XML配置文件放在mvc dispatcher servlet.XML
中。该代码中的bean属性设置器
应该放在哪里?我删除了extends HttpServlet
,并出现了2个错误…如果我附加项目的zip,会有帮助吗?您几乎是关于您的更新,您现在定义了两个InternalResourceViewResolver
。您可以删除其中一个。其次,@Autowired
意味着spring应该查看该方法,然后猜测应该在那里注入什么bean。考虑到这一点,您需要public void setDSLR
成为@Autowirede> 。一旦你这样做,你会得到的下一个例外是没有类型为DSLR
的候选bean要注入。为什么?因为在你当前的xml中没有定义DSLR
的bean。你可以通过在你的xml中引入一个DSLR
bean来解决这个问题,就像你最初所做的那样。目前,HttpServlet
的东西没有'不太重要。没有什么对该类层次结构敏感。该'servlet'作为java对象存在于Spring上下文中,Spring MVC将对其进行思考,以确定如何使其jive。一旦您能够发出映射到该控制器的请求(并且使其不会因属性注入问题而消亡),那么我们就可以担心了!在我按照您的建议进行了更改之后,现在我有了org.springframework.beans.BeanInstantiationException:无法实例化bean类[java.util.List]:指定的类是