A container class with dynamic indexes. Use this class instead of combining eg. an ArrayList (for iteration in defined order) with a HashMap (for quick lookup via some key).

Create an instance of MultiIndexContainer and create the indexes you require. Then, put and retrieve data via any of those indexes.

MultiIndexContainer<Employee> container = MultiIndexContainer.create();
SequentialIndex<Employee> bySequence = container.createSequentialIndex();
UniqueIndex<Integer, Employee> byId = container.createHashedUniqueIndex(e -> e.getId());

bySequence.add(new Employee("Jones", 1, "London"));
bySequence.add(new Employee("Miller", 2, "New York"));
bySequence.add(new Employee("Smith", 3, "Berlin"));
bySequence.add(new Employee("Miller", 4, "Bournemouth"));
[...]
boolean wasAdded = bySequence.add(new Employee("Jones", 2, "Austin"));
Assert.isFalse(wasAdded, "Adding this employee violates the uniqueness constraint of byId index");

Optional<Employee> e = byId.getOptional(3);
if (e.isPresent())
    ...

This software requires Java 8 and Guava.

To add a dependency using Maven, use the following:

<dependency>
    <groupId>com.github.mawillers</groupId>
    <artifactId>multiindex</artifactId>
    <version>1.0.0</version>
</dependency>

Run mvn test for compiling the code and running all unit tests.

• Maven - Dependency Management
• Hamcrest - Expressive matchers for JUnit
• Guava - Generic tools

We use SemVer for versioning.

• Martin Willers - Design and implementation

This project is licensed under the MIT License - see the LICENSE.md file for details

• The Boost Multi-index Containers Library for C++ gave the idea for creating this package.