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Even experienced Java developers tend to think that Java has only three protection modifiers. The language actually has four! The package private (a.k.a. default) level of visibility is often forgotten. You should pay attention to what methods you make public. The public methods in an application a...

These Java issues can be very embarrassing, and sometimes remain undiscovered until run in production. Fallthrough behavior in switch statements is often useful; however, missing a “break” keyword when such behavior is not desired can lead to disastrous results. If you have forgotten to put a “break...

Every time a program opens a resource, such as a file or network connection, it is important to free the resource once you are done using it. Similar caution should be taken if any exception were to be thrown during operations on such resources. One could argue that the FileInputStream has a finaliz...

This example is about deliberately ignoring or "squashing" exceptions. Or to be more precise, it is about how to catch and handle an exception in a way that ignores it. However, before we describe how to do this, we should first point out that squashing exceptions is generally not the co...

pip is your friend when you need to install any package from the plethora of choices available at the python package index (PyPI). pip is already installed if you're using Python 2 >= 2.7.9 or Python 3 >= 3.4 downloaded from python.org. For computers running Linux or another *nix with a native...

ASP.NET Core introduces the concept of dependency injection into Views via the @inject directive via the following syntax : @inject <type> <name> Example Usage Adding this directive into your View will basically generate a property of the given type using the given name within your ...

Amp harnesses Promises [another name for Awaitables] and Generators for coroutine creation. require __DIR__ . '/vendor/autoload.php'; use Amp\Dns; // Try our system defined resolver or googles, whichever is fastest function queryStackOverflow($recordtype) { $requests = [ Dns\qu...

In vc.h @interface vc : UIViewController<UIWebViewDelegate> in vc.m - (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{ if (navigationType == UIWebViewNavigationTypeLinkClicked){...

For Each row As DataRow In FooDataTable.Rows Me.RowsToProcess.Add(row) Next Dim myOptions As ParallelOptions = New ParallelOptions() myOptions.MaxDegreeOfParallelism = environment.processorcount Parallel.ForEach(RowsToProcess, myOptions, Sub(currentRow, state) ...

In C++, a byte is the space occupied by a char object. The number of bits in a byte is given by CHAR_BIT, which is defined in climits and required to be at least 8. While most modern systems have 8-bit bytes, and POSIX requires CHAR_BIT to be exactly 8, there are some systems where CHAR_BIT is great...

It is not possible to directly use static_cast, const_cast, dynamic_cast and reinterpret_cast on std::shared_ptr to retrieve a pointer sharing ownership with the pointer being passed as argument. Instead, the functions std::static_pointer_cast, std::const_pointer_cast, std::dynamic_pointer_cast and ...

The tree command lists the contents of a specified directory in a tree-like format. If no directory is specified then, by default, the contents of the current directory are listed. Example Output: $ tree /tmp /tmp ├── 5037 ├── adb.log └── evince-20965    └── image.FPWTJY.png Use the tree ...

curl -XGET http://www.example.com:9200/myIndexName/_search?pretty=true&q=*:* This uses the Search API and will return all the entries under index myIndexName. Reference Link: Here

Suppose we have a json ： { "total_count": 132, "page_size": 2, "page_index": 1, "twitter_posts": [ { "created_on": 1465935152, "tweet_id": 210462857140252672, "tweet": "Along with our ne...

Imagine you have all dates in all responses in some custom format, for instance /Date(1465935152)/ and you want apply general rule to deserialize all Json dates to java Date instances. In this case you need to implement custom Json Deserializer. Example of json: { "id": 1, "cr...

Of the LINQ methods which use deferred execution, some require a single value to be evaluated at a time. The following code: var lst = new List<int>() {3, 5, 1, 2}; var streamingQuery = lst.Select(x => { Console.WriteLine(x); return x; }); foreach (var i in streamingQuery) { ...

Let's take a sample class. class Book: def __init__(self, title, author): self.title = title self.author = author book1 = Book(title="Right Ho, Jeeves", author="P.G. Wodehouse") In Python you can access the attribute title of the class using the dot ...

It is possible to use IO.inspect/1 as a tool to debug an elixir program. defmodule MyModule do def myfunction(argument_1, argument_2) do IO.inspect(argument_1) IO.inspect(argument_2) end end It will print out argument_1 and argument_2 to the console. Since IO.inspect/1 returns i...

PDO is a universal database connection command in PHP, it support 12 different database type e.g MySQL, MongoDB, NoSQL. A big bonus about PDO is that it calculate your code to support the database type, so you don't need to make any chance when moving over to another database system. Summary PDO...

When a function doesn't preserve units automatically due to lower-level operations, the LanguagePrimitives module can be used to set units on the primitives that support them: /// This cast preserves units, while changing the underlying type let inline castDoubleToSingle (x : float<'u>) : fl...