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The Details of Oracle's JDK 7 and 8 'Plan B'
gkunene writes "Oracle has put Java 7 and 8 features up for Java Community approval, providing a clear indication of what the next two major versions of Java are likely to include. (Java 7 contents, Java 8 contents.) From the article: 'The JDK 7 and 8 JSRs represent Oracle's 'Plan B' approach for separating JDK 7 into two separate releases, splitting up features that were all originally intended for the Java 7 release. This approach is intended to help expedite new Java releases. Among the key components of the original Java 7 plan that are now set for inclusion in Java 8 are the Lambda and Jigsaw efforts. At JavaOne this year, Thomas Kurian, executive vice president, Oracle Product Development, explained that Lambda is all about bringing closures to the Java language. Kurian noted at the time that Lambda is intended to provide a more concise replacement for inner classes, as well as support automatically parallel operations on collections. Jigsaw is all about building modularity into the Java Virtual Machine.'"
The lack of objects hasn't ever stopped any C program from working, but its lack is what inspired C++. Similarly, Java's lack of closures is what inspired C#.
Way back in the '90s, MS wanted to enable developers to use Java to write Windows apps. The obvious way to write Windows apps is for objects (like windows and buttons) to have events (like "mouse move" and "key down") that other objects can listen for by giving the object a function to call when the event is raised. Java had no clean way to write event listeners for VB-style form designers, so MS modified their version of Java (J++) to have closures (so you can say "use this object's OnKeyDown method to handle the KeyDown event"). Since Sun decided to go with inner classes instead, they sued MS and made them stop shipping any Java at all.
As a result, MS needed to write their own Java-like language for VB-style form designer apps, and came up with C#. Obviously it has closures (which it calls "delegates"), but in version 1.0 they only closed over an object's member variables. In 2.0 they were able to be anonymous and close over local variables in a method, and in 3.0 they gained the convenient lambda syntactic sugar. Some have called Java's inner classes "syntactic vinegar" because they're so cumbersome to use compared to C#'s (and most other languages') closures.
C#'s extension methods and generics combined with type inferencing and lambdas make it very concise to write code to return a list sorted by its item's name like this: list.OrderBy(item => item.name)
It's not unreasonable for Java programmers to ask for a similar boost in their productivity.
dom