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Editorial Team
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Asked: 2026-05-27T08:47:33+00:00

lets say I have a class like this: public class MyClass { private String

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lets say I have a class like this:

public class MyClass {

    private String name;

    public MyClass(final String name) {
        this.name = name;
    }

    public static void startMe() {
        //do something
    }

    public static String gimmeString() {
        //do something
        return "myString";
    }

    public MyClass getObject(final String name) {
        //do something
        return new MyClass(name);
    }
}

At first I would like to know how to start the function “startMe” in the class MyClass with JSTL? Nothing more, just start this function. Then how to start AND display the string in the function “gimmeString”. At last (yeah it looks funny) I would like to get access to the function getObject(name) AND save this in a JSTL variable (or something so I can use this object later).

I just know that I need Beans. And after that no idea how to use it with JSTL, I have something like that:

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<jsp:useBean id="start" scope="session" class="com.MyClass"/>
<%-- and now? <c:?? --%>
</body>
</html>

Thank you

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1 Answer

  1. Editorial Team

    You can’t do that cleanly without using a preprocessing servlet or a MVC framework like JSF. The <jsp:useBean> only offers facilities to get/set model values. Nothing more. It can absolutely not supplant the Controller part of MVC.

    You could workaround this by introducing lazy loading in a getter or lazy executing in a setter.

    E.g. lazy loading:

    public String getString() {
    if (string == null) {
        start();
    }

    return string;
}

    with

    ${start.string}

    or, lazy executing:

    public void setString(String string) {
    if (this.string == null) {
        start();
    }

    this.string = string;
}

    with

    <jsp:setProperty name="start" property="string" value="somevalue" />

    Keep in mind that is an ugly hack. You should really look into servlets or MVC frameworks. If you’re still new to the stuff, start with a simple servlet. See also our servlets wiki page for some hello world examples. Note that when you’re using servlets, you do not need <jsp:useBean> and consorts anymore.

    Your concrete functional requirement is actually unclear. Particularly having a public static method in a session scoped bean is confusing. If you actually want to call a method on webapp’s startup, use ServletContextInitializer#contextInitialized(). Or if you want to call a method on creation of a session, use HttpSessionListener#sessionCreated().

    Oh, your bean’s design is incorrect. It should have a (implicit) no-arg default constructor.

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