Monday, January 14, 2013

Giving up on Java's Constructors

As much as I'm not always a fan of objective-c, I really like the method calling syntax:

    Merger merger = [[Merger alloc] initWithFirstString:"foo" andSecondString:"Bar" startingAt:1 suffleOutput:false lowercaseOutput:true];
If you wanted to write that in java, it would be fairly incomprehensible:

    Merger merger = new Merger("foo", "Bar", 1, false, true);

Just looking at this, who the hell knows what "foo" and "bar" are and why there is a number and a couple bools after it. You've have to look at the docs. Assuming you wrote docs... You could just nuke all the constructor params and create a whole lot of setters, and do this:

    Merger merger = new Merger();

But that sort of stinks too. First, it six lines of code for something that should go in one. Second, what if you want those parameters to be final?

So I've basically given up on constructors in java and added the following eclipse template to my tool belt:

            public static ${enclosing_type}Builder Builder() {
                return new ${enclosing_type}Builder();

            public static class ${enclosing_type}Builder {
            private String property = null;

            public ${enclosing_type} build() {
                Preconditions.checkState( != null,
                    "property is required.");
                return new ${enclosing_type}(;

            public ${enclosing_type}Builder property(
                final String property) {
       = property;
                return this;

It ends up being quite a bit longer than the original java code, but only slightly longer than objective-c. And I'm fairly certain that the next person that comes across my code is going to be very clear about what I was trying to do here.

If Eclipse templates had the support, I'd have it find all the members of constructors in the enclosing type for the builder and run checkState on all the final members but I'm fairly certain that would require plugin development.

What do you think?

Thursday, January 10, 2013

Another Day, Another Java-In-The-Browser security hole

This one affects even fully patched, up to date browsers.
It works like so:

  1. use any browser with java enabled
  2. visit a page
  3. owner of page can now execute arbitrary code on your computer

I love java, but, damn if it doesn't suck in the browser. This is just the latest, if you still have it enabled in your browser, now is the time to disable it. 

Do it now.

By convincing a user to visit a specially crafted HTML document, a remote attacker may be able to execute arbitrary code on a vulnerable system.

Resume Visualization: What does your resume look like?

my resume, according to Tagxedo
I like to keep my resume up to date. Every time some new task comes along, I'll add that in there somewhere. Then if a new job comes up, I'll just edit out the old stuff, make a quick attempt at removing the irrelevant things, and mail it out. 

So what is my resume saying? 

Well on the advice of my wife I threw my resume into a word cloud generator. There are a few of them, but I picked tagxedo

So what does it say about me? Well not a whole lot about the technologies that I use, but a bunch about "management", "product", "design". I suppose that would be great if I were mostly focused on more management. Or if I were a product manager. But I'm probably not.

Now lets look at some of the jobs that I might be interested it.

I just took a stab in the dark: I like kindle, I like enterprise software, so I threw in the first job description from the kindle team that caught my eye. The result: a very different word cloud.
A Kindle SDE Job Description

Now I'm not saying you should lie on your resume: that will always come back to bite you very quickly. But your resume is basically just the sign on the front of a restaurant. I've done a bunch of things, and they'll all be reflected on my resume, but I am clearly spending much more time talking about things I've done that aren't relevant to the jobs I want than I should.

Because I'm in software and everybody needs them I get reasonably good responses when I apply for jobs, but I suspect now, that I'm getting this traction in-spite of my resume, not because of it.

Time to update.

Tuesday, January 8, 2013

Write your complicated, shared code once

write once, sorta runs everywhere
One of the deadly sins of software development is duplicating logic. I won't attempt a software engineering 101 class in a blog post: but you are more or less guaranteed to create bugs when you have logic doing the same thing implemented in two different places.

There was a time when this was easy: just don't cut and paste your code. Put everything in a library, then just use your library across projects. This time pretty much ended when we started using javascript to do Interesting Things on the web. When we started also doing interesting things on phones, it was long past.

Now we end up writing lots of code twice or more, because your server is probably written in java or .net, or php, or ruby and your phone is written in objective-c, or java, or something else.

Take a look at the fairly amazing diff-match-patch library used for keeping text documents in sync:

Neil Fraser has written that library in python (both 2 and 3), java, javascript, c++, c#, lua, dart, and objective-c. While I have to admit a certain amount of awe for that guy's multilingual skills and the attention to detail necessary to get that stuff written in a way that all those implementations talk to each other correctly, I am not sure I want to spend that kind of time.

I also don't want to try to shoe-horn a project into a single common language. We tried that with Java once upon a time, we are currently trying it with javascript (in the form of node.js, and phonegap). These solutions always force you to accept some unacceptable compromise. Maybe phonegap and node.js works for your product. But chances are, someone else has something that is much better written in python and objective-c.

Write-once, run everywhere remains a non-starter in the general case.

What makes a whole lot more sense to me is to write only the code that must be shared once.

Figure out what your complicated, shared code is. If you are writing a shared text editor using diff-match-patch, it is that algorithm that is complicated, and must be shared across platforms.

Write _that_ in javascript.

Embed it in your code using a hidden WebView in IOS, Rhino in java, or maybe Ringo in Python.

There are a million embedded javascript solutions out there.

Then you are free to write the rest of your client and server independently of one another.