Book Image

Java Coding Problems - Second Edition

By : Anghel Leonard
Book Image

Java Coding Problems - Second Edition

By: Anghel Leonard

Overview of this book

The super-fast evolution of the JDK between versions 12 and 21 has made the learning curve of modern Java steeper, and increased the time needed to learn it. This book will make your learning journey quicker and increase your willingness to try Java’s new features by explaining the correct practices and decisions related to complexity, performance, readability, and more. Java Coding Problems takes you through Java’s latest features but doesn’t always advocate the use of new solutions — instead, it focuses on revealing the trade-offs involved in deciding what the best solution is for a certain problem. There are more than two hundred brand new and carefully selected problems in this second edition, chosen to highlight and cover the core everyday challenges of a Java programmer. Apart from providing a comprehensive compendium of problem solutions based on real-world examples, this book will also give you the confidence to answer questions relating to matching particular streams and methods to various problems. By the end of this book you will have gained a strong understanding of Java’s new features and have the confidence to develop and choose the right solutions to your problems.
Table of Contents (16 chapters)
1
Text Blocks, Locales, Numbers, and Math
Free Chapter
2
Objects, Immutability, Switch Expressions, and Pattern Matching
14
Other Books You May Enjoy
15
Index

169. Calling the bsearch() foreign function

The bsearch() foreign function is part of the C standard library and has the following signature (https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/bsearch):

void *bsearch(
  const void *key,
  const void *base,
  size_t num,
  size_t width,
  int ( __cdecl *compare ) (
    const void *key, const void *datum)
);

In a nutshell, this method gets pointers to a key, a sorted array (base), and a comparator. Its goal is to use the given comparator to perform a binary search of the given key in the given array. More precisely, bsearch() gets a pointer to the key, a pointer to the array, the number of elements in the array (num), the size of an element in bytes (width), and the comparator as a callback function.

The callback function gets a pointer to key and a pointer to the current element of the array to be compared with key. It returns the result of comparing these two elements.

The bsearch() function returns...