A set of exercises to teach use of Java 8 lambda syntax, and the new Streams API.

To follow the exercises:

• fork and clone the repository
• ensure you have a correctly configured, lambda-enabled Java build
  • Maven can help generate configuration for your favourite IDE, though you will likely have to set the JDK manually
  • ensure your cloned project, particularly the class ConfigureYourLambdaBuildOfJdk compiles and runs correctly
• navigate to the first exercise, Exercise_1_Test (tests are in src/test/java, in the package org.adoptopenjdk.lambda.tutorial)
• read background information in the JavaDoc, and follow instructions, making the test pass
• to find solutions check out different branches of the project. Two flavours of solutions are available: what it might have looked like before JDK 8, and what it might look like after JDK 8. Those are in branches solutions-prejava8 and solutions-postjava8 respectively.

1. Internal vs External Iteration (the forEach method)
2. Filtering and Collecting
3. Mapping
4. Method References

[More to come]

Early access builds of JDK 8 are available here.

The current tutorial is known to work with the following JDK build:

lambda-tutorial will try to track against the newest version available. If you find that you are working with a newer version of the Lambda JDK and the tutorial does not compile or run, please file an issue.

• IntelliJ IDEA on Ubuntu
• IntelliJ IDEA on MacOS
• IntelliJ IDEA deutsche Anleitung (u.a. Windows)
• Eclipse Kepler 4.3 on Windows

Note: we are hoping the instructions are not too sensitive to the OSes on which they have been performed.