When will Java 8 be the de facto current version?

Where I live and work, when someone says simply "Java," I think they have in mind Java 5/6. How long do you think it will be before people, when they say, Java, can be presumed to mean the Java that supports Lambdas?

Nobody knows, and it depends on where you are.

Java 5 and Java 6 are both past their end-of-life dates (there will be no updates anymore and no support from Oracle, unless you pay them for extended support) and still many companies seem to be still using these versions. There are even still places where people are programming in Java 1.4, without generics and all the other features that were introduced in Java 5.

It will take at least two to three years, and most likely until after the release of Java 9, before Java 8 will be the de facto current version.

If you want to be on the safe side when deploying client-side Java, I'd stick to Java 6 for the time being. Maybe a year from now, Java 7. You may be lucky enough to assume a newer version in controlled environments, like a corporate setting where the Java version can be set by corporate IT.

I think when you say "De-facto" version you really mean "most common" version. And that really depends greatly on what industry and type of company you are looking at. For example, if I were standing in a shared office space with a bunch of start-ups then I would expect them to be all over java 8 (when released) if they've not already shunned it as "uncool" and moved on to the next new hipster language that comes with stickers for their Fixie bike. But in contrast, if I were at a bank I would expect the uptake of major new language versions to be significantly slower. Like years slower.

Another factor is when the application servers upgrade. If you are deploying to WebSphere 7 (which uses Java 6 or 7), you aren't able to use Java 8. This further slows down adoption.

As Ulf noted, client side development on a corporate network is nice because you can control what people have installed. That's where I first got to use Java 7. Which was doubly convenient because you do a lot of IO in command line programs.

Jeanne Boyarsky wrote:Another factor is when the application servers upgrade. If you are deploying to WebSphere 7 (which uses Java 6 or 7), you aren't able to use Java 8. This further slows down adoption.

Right. Indeed in the company where I work we're still using Java 6. I think that we will switch to Java 8 on client side as soon as possible, but for sure not immediately.
A long test session needs to be taken.