How does a library enhance Java programming?

A library enhances Java programming primarily by providing reusable code components. This means that developers can leverage pre-existing code to perform common tasks instead of writing code from scratch. Libraries contain collections of classes and methods that offer specific functionalities, such as handling input and output, managing data, or performing complex algorithms. This allows programmers to focus on the unique aspects of their applications, saves time, improves efficiency, and reduces the likelihood of bugs since the code in libraries is often well-tested and widely used.

For instance, when a developer needs to work with dates and times, they can utilize the Java Date library rather than implementing all the necessary functionality themselves. By doing so, they avoid the complexity involved in building and maintaining such functionality while ensuring that they benefit from best practices embedded in the library's design.

The other options focus on aspects that do not fundamentally capture the primary benefit of libraries in programming. Libraries do not restrict program size, simplify all hardware interactions directly, or limit access to system resources; their main strength lies in promoting code reuse and efficiency.