Attribute name cannot be null or empty-CodePudding

I have to show the data form my database to an HTML view like a dropdown menu for that I have created an enitiy, controller and a repository packages.

moreover, I have a dedicated MySql database ready for that I have used the application properties.

CONTROLLER CLASS

import package com.data.controller;

import java.util.List;
import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;

import com.data.Entity.Location;
import com.data.repository.LocationRepository;


@Controller
public class LocationController {

    @Autowired
    private LocationRepository locRepo;
    
    @GetMapping("/")
    public String home( Model m) {
        
        List<Location> list = locRepo.findAll();
        m.addAttribute("all_places", list);
        return "index";
    
    }
    
       
}

HTML PAGE

<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<select th: each="p: ${all_places}">
    <option th:text="${p.name}"></option>
</select>
</body>
</html>

ENTITY CLASS

package com.data.Entity;
 

import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.Id;
import jakarta.persistence.Table;

@Entity
@Table(name = "location_dtls")
public class Location {

    @Id
    @GeneratedValue(strategy = jakarta.persistence.GenerationType.IDENTITY)
    private long id;
    
    @Column(name = "place_name")
    private String name;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "Location [id="   id   ", name="   name   "]";
    }   
    
}

REPOSITORY CLASS

package com.data.repository;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

import com.data.Entity.Location;


public interface LocationRepository extends JpaRepository<Location, Long> {

}

ERROR Caused by: java.lang.IllegalArgumentException: Attribute name cannot be null or empty

CodePudding user response：

In your template, you have a space between th: and each, which I guess Thymeleaf chokes on.

CodePudding user response：

There is a problem in your index.html

<select>
    <option th:each="p:${all_places}" th:value="${p.name}" th:text="${p.name}"></option>
</select>

this will resolve the issue