Tutorial by Examples: t

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; ...

This function copies data between two streams - void copy(InputStream in, OutputStream out) throws IOException { byte[] buffer = new byte[8192]; while ((bytesRead = in.read(buffer)) > 0) { out.write(buffer, 0, bytesRead); } } Example - // reading from System.in and ...

Let's say you have this line of code: printf("Hello, world!\n"); Now say you want to change the text to "Program exiting." CommandBufferMnemonicci"printf("¦");change in the ".Program exiting.\n<esc>printf("Program exiting.\n");

git log master..foo will show the commits that are on foo and not on master. Helpful for seeing what commits you've added since branching!

In Python 2, any integer larger than a C ssize_t would be converted into the long data type, indicated by an L suffix on the literal. For example, on a 32 bit build of Python: Python 2.x2.7 >>> 2**31 2147483648L >>> type(2**31) <type 'long'> >>> 2**30 10737418...

Sometimes you will make a mistake with a lengthy macro, but would rather edit it than re-record it entirely. You can do this using the following process: Put the macro on an empty line with "<register>p. If your macro is saved in register a, the command is "ap. Edit the ma...

Using else we can perform some task when the condition is not satisfied. But what if we want to check a second condition in case that the first one was false. We can do it this way: a = 9; if mod(a,2)==0 % MOD - modulo operation, return the remainder after division of 'a' by 2 disp('a is ev...

When we use a condition within another condition we say the conditions are "nested". One special case of nested conditions is given by the elseif option, but there are numerous other ways to use nested conditons. Let's examine the following code: a = 2; if mod(a,2)==0 % MOD - modulo o...