Compiled Learning Objectives

At the end of the sprint, you should be able to do the following things. Make sure to check you can do them all, and if not, go back and keep practicing until you can.

Interfaces (Prep)

• Explain what an interface is, key features of interfaces and how they differ to classes
• Explain why interfaces are useful, the problems they solve and when to use them
• Write an interface with multiple implementations and call the different implementations in a polymorphic way

Data Structures (Prep)

• Compare and contrast common data structures in Java: Maps, Sets and Lists, explaining their similarities and differences in terms of ordering, duplicates, memory allocation and data retrieval mechanism
• And to discuss in Big-O terms, the time complexity of basic insert / update / remove operations on common collections
• Given a scenario involving data, to choose the most appropriate data structure based on the above characteristics
• Instantiate different implementations of Maps, Lists and Arrays
• Use generics to enforce what can and can not be contained within Collections

Exceptions (Prep)

• Explain the difference between checked and unchecked exceptions in Java
• Explain why we have checked and unchecked exceptions
• Give examples of when to use checked and unchecked exceptions
• Handle potential nulls in Java code
• Write code using try/catch/finally and try-with-resources blocks
• Explain how exception handling is used to avoid resource leaks

Streams and Optionals (Prep)

• Use basic stream operations like filter, map, collect to perform operations on collections
• Use Java Optional to handle potentially missing objects, for example by providing a default value, or by continuing only if a value is present
• And compare the tradeoffs between using Optionals and handling nulls explicitly → especially noting that Optionals can themselves be null..!
• Use Lambdas and method references in stream operations
• Use comparators to sort objects
• Explain an example of java stream processing in terms of initialisation, intermediate and terminal operations.
• Explain what lazy evaluation is and how streams use lazy evaluation for efficiency.
• And contrast this with JS maps / filters etc - what are the key differences in how they are evaluated?
• Explain what is meant by a programming paradigm, what paradigm is associated with most of the Java you have seen so far, and which is associated with streams and optionals