Tutorial by Examples: i

Examples ES6/ES2015 to ES5 (via Babel): This ES2015 syntax // ES2015 arrow function syntax [1,2,3].map(n => n + 1); is interpreted and translated to this ES5 syntax: // Conventional ES5 anonymous function syntax [1,2,3].map(function(n) { return n + 1; }); CoffeeScript to ...

// This iterates through a range between two DateTimes // with the given iterator (any of the Add methods) DateTime start = new DateTime(2016, 01, 01); DateTime until = new DateTime(2016, 02, 01); // NOTICE: As the add methods return a new DateTime you have // to overwrite dt in the itera...

Suppose the make fails: $ make Launch it instead with make VERBOSE=1 to see the commands executed. Then directly run the linker or compiler command that you'll see. Try to make it work by adding necessary flags or libraries. Then figure out what to change, so CMake itself can pass correct argum...

Example: Invoke different constructors by passing relevant parameters import java.lang.reflect.*; class NewInstanceWithReflection{ public NewInstanceWithReflection(){ System.out.println("Default constructor"); } public NewInstanceWithReflection( String a){ ...

Reflection is useful when it is properly used for right purpose. By using reflection, you can access private variables and re-initialize final variables. Below is the code snippet, which is not recommended. import java.lang.reflect.*; public class ReflectionDemo{ public static void main(St...

Minikube creates a local cluster of virtual machines to run Kubernetes on.It is the simplest method to get your hands dirty with Kubernetes on your local machine. Documentation for Minikube can be found at http://kubernetes.io/docs/getting-started-guides/minikube/ Requirements On macOS, xhyve ...

var baseType = typeof(List<>); var genericType = baseType.MakeGenericType(typeof(String)); var instance = Activator.CreateInstance(genericType); var method = genericType.GetMethod("GetHashCode"); var result = method.Invoke(instance, new object[] { });

This iterates from 4 to 13 (inclusive). for i in 4..13 puts "this is #{i}.th number" end We can also iterate over arrays using for names = ['Siva', 'Charan', 'Naresh', 'Manish'] for name in names puts name end

If your enum class is required to have static fields, keep in mind they are created after the enum values themselves. That means, the following code will result in a NullPointerException: enum Example { ONE(1), TWO(2); static Map<String, Integer> integers = new HashMap<>(); ...

Compare two Strings ignoring case: "School".equalsIgnoreCase("school"); // true Don't use text1.toLowerCase().equals(text2.toLowerCase()); Languages have different rules for converting upper and lower case. A 'I' would be converted to 'i' in English. But in Turkish a 'I' ...

Once you installed Ubuntu, you might want to get the latest patches and updates. Using Ubuntu's easy to use package manager Aptitude, the OS along with all future packages that is installed using this manner can be kept up to date. Download the latest package lists by refreshing information from ...

The Java language provides three operator for performing bitwise shifting on 32 and 64 bit integer values. These are all binary operators with the first operand being the value to be shifted, and the second operand saying how far to shift. The << or left shift operator shifts the value g...

public class InsertIntoConcurrentHashMap { public static void main(String[] args) { ConcurrentHashMap<Integer, SomeObject> concurrentHashMap = new ConcurrentHashMap<>(); SomeObject value = new SomeObject(); Integer key = 1; SomeObject ...

import java.io.FileReader; import java.io.IOException; import javax.script.ScriptEngine; import javax.script.ScriptEngineManager; import javax.script.ScriptException; public class InterfaceImplementationExample { public static interface Pet { public void eat(); } p...

An important principle for unit testing is to separate data access from business logic. One efficient technique for this is to define interfaces for data access. Your main class always use a reference to that interface instead of direct reading or writing data. in production code the main class wil...

GWT ships with a command line utility called webAppCreator that automatically generates all the files you’ll need in order to start a GWT project. It also generates Eclipse project files and launch config files for easy debugging in GWT’s development mode. You can create a new demo application in a...

You should already have your backend REST resource available. On the client side (GWT) your need to Add RestyGwt dependency to your project with maven <dependency> <groupId>org.fusesource.restygwt</groupId> <artifactId>restygwt</artifactId> <vers...

// Obtain an instance of JavaScript engine ScriptEngineManager manager = new ScriptEngineManager(); ScriptEngine engine = manager.getEngineByName("nashorn"); try { // Set value in the global name space of the engine engine.put("name","Nashorn"); // E...

import java.util.ArrayList; import java.util.List; import static java.lang.System.out; public class PolymorphismDemo { public static void main(String[] args) { List<FlyingMachine> machines = new ArrayList<FlyingMachine>(); machines.add(new FlyingMachine())...

The way to do a JAX-WS call with basic authentication is a little unobvious. Here is an example where Service is the service class representation and Port is the service port you want to access. Service s = new Service(); Port port = s.getPort(); BindingProvider prov = (BindingProvider)port; ...