Tutorial by Examples: java

Basic reading image from java import org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.imgcodecs.Imgcodecs; //Load native library System.loadLibrary(Core.NATIVE_LIBRARY_NAME); //Mat object used to host the image Mat imageArray; //Read image file from vile system ima...

Below there is the implementation in Java using a generics approach. It is the same algorithm, which is presented above. public interface InPlaceSort<T extends Comparable<T>> { void sort(final T[] elements); } public class MergeSort < T extends Comparable < T >> implem...

Clearing the content of a web element: (note - when simulating user actions in tests, it's better to send backspace, see next action) interactionWebElement.clear(); Entering data - simulating sending keystrokes: interactionWebElement.sendKeys("Text"); interactionWebElement.sendKeys(K...

There is no imshow in the java, you need to write a method for this. This method is a Mat2bufferedImage. Takes mat object as parameter and returns image. public static void main(String[] args) { Mat frame = new Mat(); //0; default video device id VideoCapture camera = new VideoCaptur...

For simple alert: Alert simpleAlert = driver.switchTo().alert(); String alertText = simpleAlert.getText(); System.out.println("Alert text is " + alertText); simpleAlert.accept(); For Prompt alert: Alert promptAlert = driver.switchTo().alert(); String alertText = promptAlert.getT...

Explicit wait : Wait for a certain condition to occur before proceeding further in the code. WebDriver driver = new FirefoxDriver(); driver.get("http://google.com"); WebElement myElement = (new WebDriverWait(driver, 10)) .until(ExpectedConditions.presenceOfElementLocated(By.id("...

public class MergeSortBU { private static Integer[] array = { 4, 3, 1, 8, 9, 15, 20, 2, 5, 6, 30, 70, 60,80,0,9,67,54,51,52,24,54,7 }; public MergeSortBU() { } private static void merge(Comparable[] arrayToSort, Comparable[] aux, int lo,int mid, int hi) { for (int ...

Donald Knuth is often quoted as saying this: "Programmers waste enormous amounts of time thinking about, or worrying about, the speed of noncritical parts of their programs, and these attempts at efficiency actually have a strong negative impact when debugging and maintenance are considered....

public class BasicJavaBean implements java.io.Serializable{ private int value1; private String value2; private boolean value3; public BasicJavaBean(){} public void setValue1(int value1){ this.value1 = value1; } public int getValue1(){ ...

Normally the jvm's garbage collection (gc) is transparent to the user (developer/engineer). GC tuning is normally not required unless the user faces a memory leak or has an application that requires large amount of memory - both of which eventually lead to an out-of-memory exception which compels t...

Binary Literals: The integral types (byte, short, int, and long) can also be expressed using the binary number system. To specify a binary literal, add the prefix 0b or 0B to the number. Strings in switch Statements: You can use a String object in the expression of a switch statement The try-wit...

Lambda Expressions, a new language feature, has been introduced in this release. They enable you to treat functionality as a method argument, or code as data. Lambda expressions let you express instances of single-method interfaces (referred to as functional interfaces) more compactly. Method r...

public String getCitiesByCountry(String countryName) throws MalformedURLException, IOException { //Code to make a webservice HTTP request String responseString = ""; String outputString = ""; String wsURL = "http://www.webservicex.com/globalweather.asm...

import com.couchbase.client.core.endpoint.SSLEngineFactory import com.couchbase.client.java.env.DefaultCouchbaseEnvironment import com.couchbase.client.java.CouchbaseCluster object CouchbaseConnection extends App { //Create default environment object. //Set the keystone file path(downlo...

The Java Native Interface (JNI) allows you to call Java functions from native code. Here is a simple example of how to do it: Java code: package com.example.jniexample; public class JNITest { public static int getAnswer(bool) { return 42; } } Native code: int getTheAnswer(...

String json = ...; Moshi moshi = new Moshi.Builder().build(); JsonAdapter<BlackjackHand> jsonAdapter = moshi.adapter(BlackjackHand.class); BlackjackHand blackjackHand = jsonAdapter.fromJson(json); System.out.println(blackjackHand);

BlackjackHand blackjackHand = new BlackjackHand( new Card('6', SPADES), Arrays.asList(new Card('4', CLUBS), new Card('A', HEARTS))); Moshi moshi = new Moshi.Builder().build(); JsonAdapter<BlackjackHand> jsonAdapter = moshi.adapter(BlackjackHand.class); String json = jsonAdapte...

In order to create an use a custome tag,we need to follow couple of steps: Create a tag file,defining the attributes used by it and any variables which will be used by the tag a. The attributes need to have a name,their type and and required field with a boolean value b. The variables will be...

Below example shows ways to read and write csv file without any third party libraries. Write CSV public void writeToCsvFile(List<String[]> thingsToWrite, String separator, String fileName){ try (FileWriter writer = new FileWriter(fileName)){ for (String[] strings : thingsToWrit...

function getCombinations(params, combinationsResults){ if(params.length == 0) return combinationsResults; var head = params[0]; var tail = params.slice(1); var combinationsResultsCurrent = []; if(Array.isArray(head)){ _.uniq(head).forEach(function(item){ ...