Binding Properties of Primitive Wrapper Types with Spring MVC

Question

Hello folks,

It appears to me that Spring MVC cannot bind properties of primitive wrapper types(e.g. Integer, Boolean, etc). When it tries to bind such properties, it throws the following exception.

javax.servlet.ServletException: javax.servlet.jsp.JspException: javax.servlet.jsp.JspException: org.springframework.beans.NotReadablePropertyException: Invalid property 'assigned' of bean class [model.domain.Employee]: Bean property 'assigned' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
    org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:858)
    org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:791)
    org.apache.jsp.WEB_002dINF.jsp.configuration.form.defaultForm_jsp._jspService(defaultForm_jsp.java:87)
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:238)
    org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:250)
    org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1063)
    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:801)
    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.tiles.web.startup.TilesFilter.doFilter(TilesFilter.java:75)

As soon as I changed the type of the 'assigned' property(getter, setter and instance variable) from Boolean to boolean, it worked fine.

Can anyone confirm Spring MVC cannot bind properties of primitive wrapper types? If so, is there any workaround? I can't change the property type to boolean because a null value in this property means something for my application.

Thanks.

Answer 1

On workaround would be to create / register your own property editors.

Another workaround would be to add a second setter that allows you to set the property as a 'boolean'. (You may need to fiddle around with your APIs to subvert Spring's "helpful" insistence that the getter and setter types parameter / result types match. If I'm doing this kind of thing, I typically end up with two setters with different names for the same logical property.)

Answer 2

Spring MVC works fine with Boolean.

This error may appear if your getter for Boolean is named isAssigned(). According to JavaBeans naming conventions, only boolean may have this form of getter name, Boolean should have getAssigned().