如何从Controller绑定JSON数据并在View中显示名称？附请求JSON示例

First, let's look at the formatted version of the JSON you captured for clarity:

[
  {
    "id": "904c7ccd-d568-40ca-a3ab-1d097d555f52",
    "name": "BPANDE2",
    "actualName": "Pande, Bhavana (B.V.)",
    "displayName": "Pande, Bhavana (B.V.) (BPANDE2)",
    "email": "bpande2@abc.com",
    "deleted": false,
    "deletedDate": 0,
    "authenticationRealm": "f4191d4b-4331-4637-af6f-c89781687bf6",
    "isLockedOut": false,
    "lastLoginDate": 1521144701377,
    "isDeletable": true,
    "groups": [
      {
        "id": "7862c275-8eb2-42cf-895c-214c2826a0b8",
        "name": "config_vi..."
      }
    ]
  }
]

I’ll assume you’re using Spring MVC (the most common framework for this scenario) — here’s a step-by-step breakdown to make this work:

1. Map JSON to Java Entity Classes #

First, create POJO classes that mirror the JSON structure. This lets the framework automatically bind JSON data to usable objects.

Group.java (for the nested groups array) #

public class Group {
    private String id;
    private String name;

    // Standard getters and setters
    public String getId() { return id; }
    public void setId(String id) { this.id = id; }
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
}

User.java (for the main user object) #

import java.util.List;

public class User {
    private String id;
    private String name;
    private String actualName;
    private String displayName;
    private String email;
    private boolean deleted;
    private long deletedDate;
    private String authenticationRealm;
    private boolean isLockedOut;
    private long lastLoginDate;
    private boolean isDeletable;
    private List<Group> groups;

    // Focused getters/setters for your display needs
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public String getDisplayName() { return displayName; }
    public void setDisplayName(String displayName) { this.displayName = displayName; }

    // Add getters/setters for other fields as needed
}

2. Controller: Fetch, Bind, and Pass Data to the View #

In your Controller, retrieve the JSON (from an API, database, etc.), convert it to a list of User objects, and pass it to the View via the model.

import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import java.util.List;

@Controller
public class UserController {

    @GetMapping("/user-names")
    public String loadUserNames(Model model) {
        // Replace this with your actual data source (e.g., REST API call, DB query)
        String rawJson = "[{\"id\":\"904c7ccd-d568-40ca-a3ab-1d097d555f52\",\"name\":\"BPANDE2\",\"actualName\":\"Pande, Bhavana (B.V.)\",\"displayName\":\"Pande, Bhavana (B.V.) (BPANDE2)\",\"email\":\"bpande2@abc.com\",\"deleted\":false,\"deletedDate\":0,\"authenticationRealm\":\"f4191d4b-4331-4637-af6f-c89781687bf6\",\"isLockedOut\":false,\"lastLoginDate\":1521144701377,\"isDeletable\":true,\"groups\":[{\"id\":\"7862c275-8eb2-42cf-895c-214c2826a0b8\",\"name\":\"config_vi...\"}]}]";

        ObjectMapper objectMapper = new ObjectMapper();
        List<User> userList = null;

        try {
            // Convert JSON string to a List<User>
            userList = objectMapper.readValue(rawJson, new TypeReference<List<User>>() {});
        } catch (Exception e) {
            e.printStackTrace();
            // In production, handle this properly (e.g., log error and redirect to an error page)
        }

        // Pass the user list to the View
        model.addAttribute("users", userList);
        return "user-display"; // Name of your View template file
    }
}

3. View: Render the Names #

Below are examples using two common View templates: Thymeleaf (Spring Boot’s default) and JSP.

Thymeleaf Template (user-display.html) #

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <title>User Names</title>
</head>
<body>
    <h2>User Account Details</h2>

    <!-- Render users only if data exists -->
    <div th:if="${users != null and !users.isEmpty()}">
        <ul>
            <!-- Loop through each user and display their names -->
            <li th:each="user : ${users}">
                <strong>Login Name:</strong> <span th:text="${user.name}"></span><br>
                <strong>Display Name:</strong> <span th:text="${user.displayName}"></span>
            </li>
        </ul>
    </div>

    <!-- Fallback for empty data -->
    <div th:if="${users == null or users.isEmpty()}">
        <p>No user data available.</p>
    </div>
</body>
</html>

JSP Template (user-display.jsp) #

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <title>User Names</title>
</head>
<body>
    <h2>User Account Details</h2>

    <c:if test="${not empty users}">
        <ul>
            <c:forEach var="user" items="${users}">
                <li>
                    <strong>Login Name:</strong> ${user.name}<br>
                    <strong>Display Name:</strong> ${user.displayName}
                </li>
            </c:forEach>
        </ul>
    </c:if>

    <c:if test="${empty users}">
        <p>No user data available.</p>
    </c:if>
</body>
</html>

Quick Pro Tips #

• If JSON keys don’t match your Java field names, use @JsonProperty("json-key-name") on the Java field to map them explicitly.
• Always handle JSON parsing exceptions in production (don’t just print stack traces).
• Add null checks in the View to avoid runtime errors if data is missing.

内容的提问来源于stack exchange，提问作者Guru