servlets 相关问题

我想为我的应用程序构建一个注册和登录模块，但遇到了标题中的错误。我的登录.html 我想为我的应用程序构建一个注册和登录模块，但遇到了标题中的错误。我的登录.html <!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"> <title>Login</title> </head> <body> <h1>Login</h1> <form th:action="@{/login}" th:object="${login}" method="post"> Username: <input type="text" th:field="*{username}"><br/> <p th:if="${#fields.hasErrors('username')}" th:errors="*{username}"></p> Password: <input type="password" th:field="*{password}"><br/> <p th:if="${#fields.hasErrors('password')}" th:errors="*{password}"></p> <button type="submit">Login</button> </form> </body> </html> 我的用户类别： package com.webprojekt.webblog.DAO; import jakarta.persistence.*; import jakarta.validation.constraints.NotEmpty; import jakarta.validation.constraints.Pattern; import jakarta.validation.constraints.Size; import lombok.AllArgsConstructor; import lombok.Builder; import lombok.Data; import lombok.NoArgsConstructor; import java.util.List; @Data @Entity(name = "user") @Table @Builder @AllArgsConstructor @NoArgsConstructor public class User { @Id @SequenceGenerator( name = "user_sequence", sequenceName = "user_sequence", allocationSize = 1 ) @GeneratedValue( strategy = GenerationType.SEQUENCE, generator = "user_sequence" ) @Column( nullable = false ) private long id; @Column( name = "name", nullable = true, columnDefinition = "TEXT" ) private String name; @Column( name = "is_user_admin" ) boolean isAdmin; @Column( name = "username" ) @NotEmpty @Pattern(regexp = "^[a-zA-Z0-9_]+$", message = "Only letters, digits and underscores allowed") private String username; @Column( name ="password" ) @Size(min = 5, message = "your password must have at least 5 characters") private String password; @Transient private String password2; @OneToMany(mappedBy = "user") private List<Entry> entry; @OneToMany(mappedBy = "user") private List<Comment> comment; public User(String name) { this.name = name; this.isAdmin=false; } //DTO Login public User(String username, String password1) { this.username = username; this.password = password1; } //DTO registration public User( String username, String password1, String password2) { this.username = username; this.password = password1; this.password2 = password2; } public User(String name, String username, String password, String password2) { this.name = name; this.username = username; this.password = password; this.password2 = password2; } } 我的课程： package com.webprojekt.webblog.DAO; import jakarta.persistence.Entity; import jakarta.persistence.Id; import jakarta.persistence.ManyToOne; import jakarta.persistence.Table; import lombok.AllArgsConstructor; import lombok.Builder; import lombok.Data; import lombok.NoArgsConstructor; import java.time.Instant; import java.util.UUID; @Builder @NoArgsConstructor @AllArgsConstructor @Table @Data @Entity public class Session { @Id private String id = UUID.randomUUID().toString(); @ManyToOne private User user; private Instant expiresAt; public Session(User user, Instant expiresAt) { this.user = user; this.expiresAt = expiresAt; } public User getUser() { return user; } public String getId() { return id; } public void setExpiresAt(Instant expiresAt) { this.expiresAt = expiresAt; } } 和会话控制器： package com.webprojekt.webblog.API; import com.webprojekt.webblog.BussinesLayer.WebBlogServices; import com.webprojekt.webblog.DAO.Session; import com.webprojekt.webblog.DAO.User; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.validation.BindingResult; import org.springframework.validation.FieldError; import org.springframework.web.bind.annotation.CookieValue; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.PostMapping; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServletResponse; import java.time.Instant; import java.util.Optional; @Controller public class SessionController { private WebBlogServices webBlogServices; @Autowired public SessionController(WebBlogServices webBlogServices) { this.webBlogServices = webBlogServices; } @GetMapping("/login") public String login(Model model) { model.addAttribute("login", new User ("", "")); return "login"; } @PostMapping("/login") public String login(@ModelAttribute("login") User user, BindingResult bindingResult, HttpServletResponse response) { Optional<User> optionalUser = webBlogServices.findByUsernameAndPassword(user.getUsername(), user.getPassword ()); if (optionalUser.isPresent()) { Session session = new Session(optionalUser.get(), Instant.now().plusSeconds(7*24*60*60)); //expires one week from now webBlogServices.addSession(session); //store the session ID in a cookie to keep the username secret Cookie cookie = new Cookie("sessionId", session.getId()); response.addCookie(cookie); // Login successful return "redirect:/"; } bindingResult.addError(new FieldError ("login", "password", "Login not successful.")); return "login"; } @PostMapping("/logout") public String logout(@CookieValue(value = "sessionId", defaultValue = "") String sessionId, HttpServletResponse response) { Optional<Session> optionalSession = webBlogServices.findByIdAndExpiresAtAfter(sessionId, Instant.now()); optionalSession.ifPresent(session -> webBlogServices.delete(session)); Cookie cookie = new Cookie("sessionId", ""); cookie.setMaxAge(0); response.addCookie(cookie); return "redirect:/"; } } 控制台日志： 2023-02-26T18:44:00.439+01:00 ERROR 10952 --- [nio-8080-exec-4] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: java.lang.IllegalStateException: No primary or single unique constructor found for interface javax.servlet.http.HttpServletResponse] with root cause java.lang.IllegalStateException: No primary or single unique constructor found for interface javax.servlet.http.HttpServletResponse at org.springframework.beans.BeanUtils.getResolvableConstructor(BeanUtils.java:266) ~[spring-beans-6.0.4.jar:6.0.4] at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.createAttribute(ModelAttributeMethodProcessor.java:219) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor.createAttribute(ServletModelAttributeMethodProcessor.java:85) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:147) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:122) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:181) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:148) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:884) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1080) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:973) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1011) ~[spring-webmvc-6.0.4.jar:6.0.4] at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:914) ~[spring-webmvc-6.0.4.jar:6.0.4] at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:731) ~[tomcat-embed-core-10.1.5.jar:6.0] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.0.4.jar:6.0.4] at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:814) ~[tomcat-embed-core-10.1.5.jar:6.0] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:223) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-10.1.5.jar:10.1.5] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.4.jar:6.0.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.4.jar:6.0.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.0.4.jar:6.0.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.4.jar:6.0.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:177) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:119) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:400) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:859) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1734) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-10.1.5.jar:10.1.5] at java.base/java.lang.Thread.run(Thread.java:1589) ~[na:na] 到目前为止，我可能尝试了通过谷歌找到的所有解决方案，但没有得到解决方案。这是我第一次使用 Lombok 和 HttpServletResponse 等技术。我知道我无法在java中实例化接口，但我不知道如何解决它。提前谢谢你们了。编辑1：我的 pom.xml: <?xml version="1.0" encoding="UTF-8"?> 4.0.0 org.springframework.boot spring-boot-starter-父级 3.0.2 塔利亚社区图书馆 0.0.1-快照图书馆图书馆 17 org.springframework.boot spring-boot-starter-数据-jpa org.springframework.boot spring-boot-starter-jdbc <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>com.mysql</groupId> <artifactId>mysql-connector-j</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.mariadb.jdbc</groupId> <artifactId>mariadb-java-client</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.postgresql</groupId> <artifactId>postgresql</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-validation</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> <optional>true</optional> </dependency> <dependency> <groupId>jakarta.servlet</groupId> <artifactId>jakarta.servlet-api</artifactId> <version>4.0.4</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> 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