Here’s our List with string values −List myList = Arrays.asList("One", "Two", "Three", "Four", "Five");Now, let us convert this List to Stream −Stream s = myList.stream();Following is the program to convert List to Stream in Java −Exampleimport java.util.*; import java.util.stream.*; import java.util.function.Function; public class Demo {    public static void main(String args[]) {       List myList = Arrays.asList("One", "Two", "Three", "Four", "Five");       System.out.println("List: " + myList);       Stream s = myList.stream();       System.out.println("Stream (List to Stream) = " + Arrays.toString(s.toArray()));    } }OutputList: [One, Two, Three, Four, Five] Stream (List to Stream) ... Read More

Here’s our List of String −List listString = Arrays.asList("25", "50", "75", "100", "125", "150");Now, convert the list of string to list of integer −List listInteger = listString.stream().map(Integer::parseInt).collect(Collectors.toList());Following is the program to convert List of String to List of Integer in Java −Exampleimport java.util.*; import java.util.stream.*; import java.util.function.*; public class Demo {    public static void main(String[] args) {       List listString = Arrays.asList("25", "50", "75", "100", "125", "150");       System.out.println("List of String = " + listString);       List listInteger = listString.stream().map(Integer::parseInt)          .collect(Collectors.toList());       System.out.println("List of Integer (converted from ... Read More

Here’s our List of Integer −List listInteger = Arrays.asList(25, 50, 75, 100, 125, 150);Now, convert List of Integer to List of String −List listString = listInteger.stream()    .map(s -> String.valueOf(s))    .collect(Collectors.toList());Following is the program to convert List of Integer to List of String in Java −Exampleimport java.util.*; import java.util.stream.*; import java.util.function.*; public class Demo {    public static void main(String[] args) {       List listInteger = Arrays.asList(25, 50, 75, 100, 125, 150);       System.out.println("List of Integer = " + listInteger);       List listString = listInteger.stream()          .map(s -> String.valueOf(s))   ... Read More

The contains() function of the Ints class is used to check whether an element is present in the array or not.Following is the syntax −public static boolean contains(int[] arr, int target)Here, arr is the array wherein the element is to be checked. The target is the element to be checked.Following is an example to implement the contains() method of the Ints class −Exampleimport com.google.common.primitives.Ints; import java.util.*; class Demo {    public static void main(String[] args) {       int[] myArr1 = { 100, 150, 230, 300, 400 };       int[] myArr2 = { 450, 550, 700, 800, ... Read More

The concat() function in Ints class is used to concatenate the arrays passed as parameter. The syntax is as follows −public static int[] concat(int[]... arr)Here, parameter arr is zero or more integer arrays.Let us see an example −Exampleimport com.google.common.primitives.Ints; import java.util.*; class Demo {    public static void main(String[] args) {       int[] myArr1 = { 100, 150, 230, 300, 400 };       int[] myArr2 = { 450, 550, 700, 800, 1000 };       System.out.println("Array 1 = ");       for(int i=0; i < myArr1.length; i++) {          System.out.println(myArr1[i]);   ... Read More

The asList() method of the Ints class in Java Guava’s returns a fixed-size list backed by the specified array. The syntax is as follows −public static List    asList(int[] arr)Here, arr is the array to back the list.Let us see an example to implement the asList() method of the Ints class −Exampleimport com.google.common.primitives.Ints; import java.util.List; class Demo {    public static void main(String[] args) {       int arr[] = { 20, 30, 40, 60, 80, 90, 120, 150 };       System.out.println("Array elements = ");       for(int i = 0; i < arr.length; i++) { ... Read More

The java.lang.Integer.toHexString() method returns a string representation of the integer argument as an unsigned integer in base 16.Let us now see an example −Exampleimport java.lang.*; public class Main {    public static void main(String[] args) {       int i = 160;       System.out.println("Number = " + i);       System.out.println("Hex = " + Integer.toHexString(i));    } }OutputNumber = 160 Hex = a0ExampleLet us now see another example for negative number −import java.lang.*; public class Main {    public static void main(String[] args) {       int i = -160;       System.out.println("Number = " + i);       System.out.println("Hex = " + Integer.toHexString(i));    } }OutputNumber = -160 Hex = ffffff60

The java.lang.Math.signum(float f) returns the signum function of the argument; zero if the argument is zero, 1.0f if the argument is greater than zero, -1.0f if the argument is less than zero.Let us now see an example −Exampleimport java.security.*; import java.util.*; public class Main {    public static void main(String[] argv) {       // get two float numbers       float x = 50.14f;       float y = -4f;       // call signum for both floats and print the result       System.out.println("Math.signum(" + x + ")=" + Math.signum(x));       ... Read More

The string representation for the signature object can be obtained using the method getString() in the class java.security.Signature. This includes information such as the object state, algorithm name etcLet us now see an example −Exampleimport java.security.*; import java.util.*; public class Main {    public static void main(String[] argv) {       try {          Signature signature = Signature.getInstance("SHA256withRSA");          String str = signature.toString();          System.out.println(str);       } catch (NoSuchAlgorithmException e) {          System.out.println("Error!!! NoSuchAlgorithmException");       }    } }OutputSignature object: SHA256withRSALet us now ... Read More

The initSign() method initialize this object for signing. If this method is called again with a different argument, it negates the effect of this call.Let us now see an example −Exampleimport java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.PrivateKey; import java.security.Signature; import java.util.Scanner; public class Main {    public static void main(String args[]) throws Exception {       //Creating KeyPair generator object       KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("DSA");       //Initializing the key pair generator       keyPairGen.initialize(2048);       //Generate the pair of keys       KeyPair pair = keyPairGen.generateKeyPair();       //Getting the privatekey ... Read More