An IntStream interface extends the BaseStream interface in Java 8. It is a sequence of primitive int-value elements and a specialized stream for manipulating int values. We can also use the IntStream interface to iterate the elements of a collection in lambda expressions and method references.Syntaxpublic interface IntStream extends BaseStreamExampleimport java.util.stream.IntStream; public class StringToIntegerStreamTest {    public static void main(String[] args) {       String str = "Tutorials Point";       IntStream stream = str.chars();       stream.forEach(element -> System.out.println(((char)element))); // using lambda expression    } }OutputT u t o r i a l s P o i n tExampleimport java.util.*; ... Read More

BooleanSupplier is a functional interface defined in the "java.util.function" package. This interface can be used as an assignment target for a lambda expression or method reference. BooleanSupplier interface has only one method getAsBoolean() and returns a boolean result, true or false.Syntax@FunctionalInterface public interface BooleanSupplier {    boolean getBoolean(); }Exampleimport java.util.function.BooleanSupplier; public class BooleanSupplierLambdaTest {    public static void main(String[] args) {       BooleanSupplier Obj1 = () -> true;       BooleanSupplier Obj2 = () -> 5 < 50; // lambda expression       BooleanSupplier Obj3 = () -> "tutorialspoint.com".equals("tutorix.com");       System.out.println("Result of Obj1: " + Obj1.getAsBoolean());       ... Read More

A FileFilter is a functional interface from the "java.io" package. It can be used as the assignment target for a lambda expression or method reference. An instance of the FileFilter interface passed to the listFiles() method of the File class. FileFilter interface having one abstract method accept() and it tests whether or not the specified abstract pathname has included in a pathname list.Syntax@FunctionalInterface public interface FileFilterExampleimport java.io.File; import java.io.FileFilter; public class FileFilterTest {    public static void main(String[] args) {       File dir = new File("C:/Program Files/Java/jdk1.8.0_211");       File[] subDir = dir.listFiles((file) -> {    // lambda expression         ... Read More

A PropertyChangeListener is a functional interface from java.beans package. It has one abstract method propertyChange() and gets called when a bound property is changed. This method takes a PropertyChangeEvent argument that has details about an event source and the property that has changed. A PropertyChangeSupport can be used by beans that support bound properties. It can manage a list of listeners and dispatches property change events. The PropertyChangeListener's implementer does the role of an Observer and bean wrapping the PropertyChangeSupport is Observable.Syntaxvoid propertyChange(PropertyChangeEvent evt)Exampleimport java.beans.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.border.*; public class PropertyChangeListenerLambdaTest {    public static void main(String [] args) {   ... Read More

Lambda expression is the anonymous representation of a function descriptor of a functional interface. As we know that all collection interfaces like List, Set and Queue use an Iterable as their super interface. Since Java 8, an Iterable interface introduces a new method called forEach(). This method performs an action on the contents of Iterable in the order elements that occur when iterating until all elements have processed.Syntaxvoid forEach(Consumer

UnaryOperator is a functional interface that extends the Function interface. It represents an operation that accepts a parameter and returns a result of the same type as its input parameter. The apply() method from Function interface and default methods: andThen() and compose() are inherited from the UnaryOperator interface. A lambda expression and method reference can use UnaryOperator objects as their target.Syntax@FunctionalInterface public interface UnaryOperator extends FunctionExample-1import java.util.function.UnaryOperator; public class UnaryOperatorTest1 {    public static void main(String[] args) {       UnaryOperator operator = t -> t * 2;   // lambda expression       System.out.println(operator.apply(5));       System.out.println(operator.apply(7));       System.out.println(operator.apply(12));    } }Output10 ... Read More

BinaryOperator is one of a functional interface from java.util.function package and having exactly one abstract method. A lambda expression or method reference uses BinaryOperator objects as their target. BinaryOperator interface represents a function that takes one argument of type T and returns a value of the same type.BinaryOperator Interface contains two static methods, minBy() and maxBy(). The minBy() method returns a BinaryOperator that returns the greater of two elements according to a specified Comparator while the maxBy() method returns a BinaryOperator that returns the lesser of two elements according to a specified Comparator.Syntax@FunctionalInterface public interface BinaryOperator extends BiFunctionExampleimport java.util.function.BinaryOperator; public class BinaryOperatorTest {    public static void main(String[] args) {       BinaryOperator ... Read More

The CharMatcher class determines a true or false value for any Java char value, just as Predicate does for any Object.Sr.NoMethods & Description1CharMatcher and(CharMatcher other)Returns a matcher that matches any character matched by both this matcher and other.2static CharMatcher anyOf(CharSequence sequence)Returns a char matcher that matches any character present in the given character sequence.3boolean apply(Character character)Deprecated. Provided only to satisfy the Predicate interface; use matches(char) instead.4String collapseFrom(CharSequence sequence, char replacement)Returns a string copy of the input character sequence, with each group of consecutive characters that match this matcher replaced by a single replacement character.5int countIn(CharSequence sequence)Returns the number of matching ... Read More

In this article, we will learn how to generate a string representation of the contents of arrays in Java. Using Arrays.deepToString() transforms arrays into readable strings, making it easy to visualize their structure. This method is particularly useful for one-dimensional and multidimensional arrays. Problem StatementGiven arrays with varying structures, write a Java program that prints the elements of these arrays and their string representations using Arrays.deepToString().Input A one-dimensional array:Object[] ob = {"One", "Two", "Three", "Four"} A two-dimensional array:int[][] arr = {{10, 20, 30}, {40, 50, 75}, {100, 150, 200}}Output For the one-dimensional array:Array elements...Value = OneValue = TwoValue ... Read More

The CaseFormat class is a utility class for converting between various ASCII case formats −Modifier and TypeMethod and DescriptionObjectclone()Overrides Cloneable.booleanequals(Object obj)Overrides equals.String.format(double number)Specialization of format.abstract StringBufferformat(double number, StringBuffer toAppendTo, FieldPosition pos)Specialization of format.Stringformat(long number)Specialization of format.abstract StringBufferformat(long number, StringBuffer toAppendTo, FieldPosition pos)Specialization of format.ExampleLet us now see an example to implement the CaseFormat class with java file GuavaTester.java −import com.google.common.base.CaseFormat; public class GuavaTester {    public static void main(String args[]) {       GuavaTester tester = new GuavaTester();       tester.testCaseFormat();    }    private void testCaseFormat() {       String data = "test_data";       ... Read More