How to loop through a HashMap in JSP?

Just the same way as you would do in normal Java code.

for (Map.Entry<String, String> entry : countries.entrySet()) {    String key = entry.getKey();    String value = entry.getValue();    // ...}

However, scriptlets (raw Java code in JSP files, those <% %> things) are considered a poor practice. I recommend to install JSTL (just drop the JAR file in /WEB-INF/lib and declare the needed taglibs in top of JSP). It has a <c:forEach> tag which can iterate over among others Maps. Every iteration will give you a Map.Entry back which in turn has getKey() and getValue() methods.

Here's a basic example:

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %><c:forEach items="${map}" var="entry">    Key = ${entry.key}, value = ${entry.value}<br></c:forEach>

Thus your particular issue can be solved as follows:

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %><select name="country">    <c:forEach items="${countries}" var="country">        <option value="${country.key}">${country.value}</option>    </c:forEach></select>

You need a Servlet or a ServletContextListener to place the ${countries} in the desired scope. If this list is supposed to be request-based, then use the Servlet's doGet():

protected void doGet(HttpServletRequest request, HttpServletResponse response) {    Map<String, String> countries = MainUtils.getCountries();    request.setAttribute("countries", countries);    request.getRequestDispatcher("/WEB-INF/page.jsp").forward(request, response);}

Or if this list is supposed to be an application-wide constant, then use ServletContextListener's contextInitialized() so that it will be loaded only once and kept in memory:

public void contextInitialized(ServletContextEvent event) {    Map<String, String> countries = MainUtils.getCountries();    event.getServletContext().setAttribute("countries", countries);}

In both cases the countries will be available in EL by ${countries}.

Hope this helps.

See also:

• Iterate over elements of List and Map using JSTL <c:forEach> tag
• How to iterate over a nested map in <c:forEach>
• How to iterate an ArrayList inside a HashMap using JSTL?
• Using special auto start servlet to initialize on startup and share application data

Depending on what you want to accomplish within the loop, iterate over one of these instead:

• countries.keySet()
• countries.entrySet()
• countries.values()

Below code works for me

first I defined the partnerTypesMap like below in the server side,

Map<String, String> partnerTypes = new HashMap<>();

after adding values to it I added the object to model,

model.addAttribute("partnerTypesMap", partnerTypes);

When rendering the page I use below foreach to print them one by one.

<c:forEach items="${partnerTypesMap}" var="partnerTypesMap">      <form:option value="${partnerTypesMap['value']}">${partnerTypesMap['key']}</form:option></c:forEach>