Spring MVC - JSTL forEach Tag with Example

The forEach tag in JSTL is one of the most commonly used tags. It allows you to iterate over collections such as lists, arrays, and maps. The tag is part of the JSTL core library.

Let's set up a simple Spring MVC application that uses the forEach tag to display a list of users.

1. Maven Dependencies

Make sure you have the necessary dependencies:

<!-- Spring Web MVC -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>${spring.version}</version>
</dependency>

<!-- JSTL -->
<dependency>
    <groupId>javax.servlet.jsp.jstl</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>

2. Model

Assume we have a simple User model:

public class User {
    private String name;
    private String email;

    // Constructors, getters, setters, etc.
}

3. Controller

Here's a controller that sends a list of users to a JSP view:

@Controller
@RequestMapping("/users")
public class UserController {

    @GetMapping("/list")
    public String listUsers(Model model) {
        List<User> users = Arrays.asList(
                new User("Alice", "alice@example.com"),
                new User("Bob", "bob@example.com"),
                new User("Charlie", "charlie@example.com")
        );

        model.addAttribute("users", users);
        return "userList";
    }
}

4. JSP View with JSTL `forEach`

In your userList.jsp:

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<!DOCTYPE html>
<html>
<head>
    <title>Users List</title>
</head>
<body>

<h2>List of Users:</h2>
<table border="1">
    <thead>
        <tr>
            <th>Name</th>
            <th>Email</th>
        </tr>
    </thead>
    <tbody>
        <c:forEach var="user" items="${users}">
            <tr>
                <td>${user.name}</td>
                <td>${user.email}</td>
            </tr>
        </c:forEach>
    </tbody>
</table>

</body>
</html>

In this JSP view, the forEach tag iterates over the list of users and for each user, it displays their name and email in a table row.

5. Run and Test

Run your Spring MVC application, navigate to /users/list, and you should see a table displaying the list of users.

Remember, forEach can also be used with arrays, maps, and even simple ranges using the begin, end, and step attributes.

Spring MVC JSTL forEach Tag Example:

Description: This is a basic example showcasing the use of <c:forEach> tag in a JSP page with JSTL in a Spring MVC application.

Code Snippet: (JSP Page)

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!-- Other JSP content -->
<c:forEach var="item" items="${itemList}">
    <!-- Process each item in the list -->
    ${item}
</c:forEach>

Using c:forEach in Spring MVC with JSTL:
- Description: This example demonstrates using <c:forEach> in a Spring MVC application with JSTL. It includes iterating over a collection and processing each element.
- Code Snippet: (JSP Page)
```
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<c:forEach var="user" items="${userList}">
    
    ${user.username}
</c:forEach>
```
Iterating Over a Collection with c:forEach in Spring MVC:
- Description: This example focuses on using <c:forEach> in Spring MVC to iterate over a collection and display its elements in a JSP page.
- Code Snippet: (JSP Page)
```
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<c:forEach var="book" items="${bookList}">
    
    ${book.title}
</c:forEach>
```
JSTL forEach Loop in Spring MVC Example:
- Description: This example illustrates using JSTL's <c:forEach> loop in a Spring MVC application to iterate over a collection and perform actions on each element.
- Code Snippet: (JSP Page)
```
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<c:forEach var="item" items="${itemsList}">
    
    ${item.property}
</c:forEach>
```

Displaying a List on JSP using c:forEach in Spring MVC:

Description: This example demonstrates using <c:forEach> to display a list on a JSP page in a Spring MVC application.

Code Snippet: (JSP Page)

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!-- Other JSP content -->
<c:forEach var="item" items="${itemList}">
    <!-- Display each item in the list -->
    ${item}
</c:forEach>

How to Use c:forEach for Iteration in Spring MVC JSTL:

Description: This example provides guidance on how to use <c:forEach> for iteration in a Spring MVC application with JSTL.

Code Snippet: (JSP Page)

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!-- Other JSP content -->
<c:forEach var="element" items="${elementList}">
    <!-- Process each element in the list -->
    ${element.property}
</c:forEach>

Spring MVC JSTL forEach Loop with Objects:

Description: This example demonstrates using <c:forEach> in a Spring MVC application with JSTL to iterate over a collection of objects and display their properties.

Code Snippet: (JSP Page)

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!-- Other JSP content -->
<c:forEach var="employee" items="${employeeList}">
    <!-- Display properties of each employee -->
    ${employee.name}
</c:forEach>

Nested c:forEach in Spring MVC JSTL:

Description: This example illustrates the usage of nested <c:forEach> loops in a Spring MVC application with JSTL. It includes iterating over a nested collection.

Code Snippet: (JSP Page)

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!-- Other JSP content -->
<c:forEach var="department" items="${departments}">
    <!-- Display department details -->
    ${department.name}
    <c:forEach var="employee" items="${department.employees}">
        <!-- Display employee details within the department -->
        ${employee.name}
    </c:forEach>
</c:forEach>

Dynamic Iteration with c:forEach in Spring MVC:
- Description: This example showcases dynamic iteration using <c:forEach> in a Spring MVC application. It includes dynamically changing the iteration count based on a variable.
- Code Snippet: (JSP Page)
```
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<c:forEach var="i" begin="1" end="${iterationCount}">
    
    ${i}
</c:forEach>
```

Using c:forEach for Iterating Through a Map in Spring MVC JSTL:

Description: This example demonstrates using <c:forEach> to iterate through a map in a Spring MVC application with JSTL.

Code Snippet: (JSP Page)

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!-- Other JSP content -->
<c:forEach var="entry" items="${myMap}">
    <!-- Display key and value of each map entry -->
    Key: ${entry.key}, Value: ${entry.value}
</c:forEach>

Spring MVC - JSTL forEach Tag with Example

1. Maven Dependencies

2. Model

3. Controller

4. JSP View with JSTL forEach

5. Run and Test

4. JSP View with JSTL `forEach`