Implementing Flash Scope in Java Web Applications

Steve Neal Development, Java Programming 6 Comments

While working recently on a Spring MVC project I found myself wishing it supported flash scope. I hunted around for a simple solution but couldn’t find anything that didn’t rely on having to import large framework libraries. After a little thought I came up with the following simple and lightweight solution that has worked really well for me. I’ve included …

Using recursion to program in JSP

Steve Neal Development Leave a Comment

I needed to render a tree structure in a JSP and wanted to use a recursive solution like this: After a while of not getting very far with this and trying to figure out why I was getting stack overflow errors, I figured out that the jsp:param tag was not passing the state across as I’d expected in the recursive …

Address in Use Error using Tomcat on Windows XP

Steve Neal Development 2 Comments

Occasionally you might get an error like this when launching Tomcat: java.net.BindException: Address already in use: JVM_Bind <null>:8080 This can be caused if you already have Tomcat running as it will hold onto a network port for handling HTTP requests. In the above example the port shown is 8080. However, this error is sometimes apparent even when Tomcat has already …

Working around a javax.net.ssl.SSLHandshakeException

Steve Neal Development 1 Comment

When trying to download data from an HTTPS connection, you might see the following exception reported: javax.net.ssl.SSLHandshakeException: renegotiation is not allowed This rather unhelpful error message can be raised on either the server or the client and indicates that the SSL libraries in Java cannot determine whether the CA that signed the server’s certificate is to be trusted or not. …

Getting a “Netscape security model is no longer supported” error when using IntelliJ

Steve Neal Java Programming 1 Comment

I’ve been working on a JMS application that uses encryption with JNDI authentication and have encountered the following error message when running it: Netscape security model is no longer supported. Please migrate to the Java 2 security model instead. It turns out that this is a problem with the JDK’s plugin.jar file and can be fixed quite easily by removing …

Java 1.4 Debugger Not Working?

Steve Neal Development 1 Comment

There’s a bug that I’d encountered running the debugger in JDK 1.4.2 ages ago that reared it’s head again today. I’ve been working on a system that uses this old JDK and thought I’d note the solution here in case I ever came across it again. The problem is encountered when the JVM is launched in debug mode and is …