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Use Lambda Expressions Without Java 8

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Use Lambda Expressions Without Java 8

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One of the things that makes developers excited about Java 8 is the ability to use lambda expressions in their code. But what if you are using an earlier version of Java? Esko Luontola has the answer for you!  

After asking if anything existed that backported lambda expressions to Java 7, and getting no answers, he just went ahead an built Retolambda  himself.  The project works as follows: 

 will take bytecode compiled with Java 8 and convert it to run on Java 7, 6 and 5 runtimes, letting you use lambda expressions and method references on those platforms.

What I love about this story is how, on seeing there was no library available for what he needed, Esko built it himself; no complaining about how it didn't exist, just code and build. True innovation and drive.

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