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javaintellij-ideathymeleaf

Thymeleaf Exception evaluating SpringEL

I'm a novice just learning using intellij idea and Thymeleaf,

Why can't I find out how to fix this problem how ever I try.

UserController.java

package com.test01.controller;

import com.test01.model.User;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
@RequestMapping("/user")
public class UserController {
    @GetMapping("/register")
    public String doDefault(){
        return "register";
    }

    @PostMapping("/register")
    public String register(User user) {
        return "success";
    }
}

User.java

package com.test01.model;

import lombok.AllArgsConstructor;
import lombok.Data;

@AllArgsConstructor
@Data
public class User {
    private Integer id;
    private String username;
    private String password;
}

register.html

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
  <meta charset="UTF-8">
  <title>register</title>
</head>
<body>
<form th:action="@{/user/register}" method="post">
  <table border="0">
    <tr>
      <td>username:</td>
      <td><input type="text" name="username"/></td>
    </tr>
    <tr>
      <td>password:</td>
      <td><input type="password" name="password" /></td>
    </tr>
    <tr>
      <td><input type="submit" value="submit" /></td>
      <td><input type="reset" value="reset"></td>
    </tr>
  </table>
</form>
</body>
</html>

success.html

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
  <meta charset="UTF-8">
  <title>success</title>
</head>
<body th:object="${user}">
<h3>[[*{usesrname}]]，success! </h3>
<table border="0">
  <caption>Your registration information is</caption>

  <tr>
    <td>username:</td>
    <td th:text="*{username}"></td>
  </tr>

  <tr>
    <td>password:</td>
    <td th:text="*{password}"></td>
  </tr>
</table>

</body>
</html>

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Cannot resolve 'username' Cannot resolve 'password'

Solution 
  • package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class TestProgramApplication {

    public static void main(String[] args) {
        SpringApplication.run(TestProgramApplication.class, args);
    }

}

    User.java

    package com.example;

public class User {
    private Integer id;
    private String username;
    private String password;
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    
    
}

    UserController.java

    package com.example;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;

@Controller
public class UserController {

    @GetMapping("/register")
    public String doDefault() {
        return "register";
    }

    @PostMapping("/user/register")
    public String register(User user) {
        return "success";
    }
}

    register.html

    <!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<title>register</title>

<head>
    <meta charset="ISO-8859-1">
    <title>Insert title here</title>
</head>

<body>


    <form th:action="@{/user/register}" method="post">
        <table border="0">
            <tr>
                <td>username:</td>
                <td><input type="text" name="username" /></td>
            </tr>
            <tr>
                <td>password:</td>
                <td><input type="password" name="password" /></td>
            </tr>
            <tr>
                <td><input type="submit" value="submit" /></td>
                <td><input type="reset" value="reset"></td>
            </tr>
        </table>
    </form>


</body>

</html>

    success.html

    <!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<title>success</title>

<head>
    <meta charset="ISO-8859-1">
    <title>Insert title here</title>
</head>

<body th:object="${user}">
    <h3>[[*{username}]]，success! </h3>
    <table border="0">
        <caption>Your registration information is</caption>

        <tr>
            <td>username:</td>
            <td th:text="*{username}"></td>
        </tr>

        <tr>
            <td>password:</td>
            <td th:text="*{password}"></td>
        </tr>
    </table>

</body>

</html>

    pom.xml

    <?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.1.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>TestProgram</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>TestProgram</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <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>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

    register page register page

    success page success page

    project structure

    project structure