Java 8 example to sort stream of objects by multiple fields using comparators and Comparator.thenComparing() method. This method returns a lexicographic-order comparator with another comparator. It gives the same effect as SQL group by clause.
Java Comparator interface used to sort a array or list of objects based on custom order. Custom ordering of elements is imposed by implementing Comparator.compare() method in the objects.
Java Comparable interface is part of Collection Framework. Learn the purpose of Comparable interface and use it in different scenarios. 1. Comparable Interface 1.1. Why Implement Comparable? In Java, if we want to sort a List of elements then we can Collections.sort() method. It sorts the list items according to …
Java String compareToIgnoreCase() example compares two strings lexicographically ignoring case. Learn how it differs from equalsIgnoreCase().
Java String compareTo() method example. Learn to compare two strings lexicographically. We can consider this string comparison dictionary based comparison.
Java String.equalsIgnoreCase() compares the current string with the specified string in a case-insensitive manner. Learn with examples.
Learn to compare the content of two String objects in a case-sensitive manner using the String.equals() API. For case-insensitive comparison, we can use the equalsIgnoreCase() method. Never use ‘==’ operator for checking the strings equality. It verifies the object references, not the content, which is undesirable in most cases. 1. String.equals() API …
Learn to compare double or compare float to avoid unexpected results caused by minor rounding errors during conversions at lower level program execution.
Learn to create a Comparator instance with lambda expressions, method references and chaining multiple comparators for complex comparisons.
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