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How to check for valid email address? [duplicate]
Is there a good way to check a form input using regex to make sure it is a proper style email address? Been searching since last night and everybody that has answered peoples questions regarding this topic also seems to have problems with it if it is a subdomained email address.
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When and how should I use a ThreadLocal variable?
... object (I'm looking at you, SimpleDateFormat). Instead, give each thread its own instance of the object.
For example:
public class Foo
{
// SimpleDateFormat is not thread-safe, so give one to each thread
private static final ThreadLocal<SimpleDateFormat> formatter = new ThreadLocal...
SQL JOIN - WHERE clause vs. ON clause
After reading it, this is not a duplicate of Explicit vs Implicit SQL Joins .
The answer may be related (or even the same) but the question is different.
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Can two applications listen to the same port?
...lications on the same machine bind to the same port and IP address? Taking it a step further, can one app listen to requests coming from a certain IP and the other to another remote IP?
I know I can have one application that starts off two threads (or forks) to have similar behavior, but can two ap...
window.onload vs
...d the onload event of the body tag? when do I use which and how should it be done correctly?
13 Answers
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Textarea that can do syntax highlighting on the fly?
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It's not possible to achieve the required level of control over presentation in a regular textarea.
If you're OK with that, try CodeMirror or Ace (formerly skywriter and bespin), or Monaco (used in MS VSCode).
From the dupl...
Avoid synchronized(this) in Java?
... an
"accidentally" variant)
I'm more worried about accidentally. What it amounts to is that this use of this is part of your class' exposed interface, and should be documented. Sometimes the ability of other code to use your lock is desired. This is true of things like Collections.synchronize...
How to run a shell script in OS X by double-clicking?
...ipt that has user execution permission on OS X, but when I double click on it, it opens in a text editor. How can I get it to run by double-clicking it?
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What is the difference between Polymer elements and AngularJS directives?
...n an import.
Nothing "links" <x-foo> to x-foo.html. In your example, it's assumed the Custom Element definition of <x-foo> (e.g. <element name="x-foo">) is defined in x-foo.html. When the browser sees that definition, it's registered as a new element.
On to questions!
What is th...
Deleting an object in java?
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You should remove the references to it by assigning null or leaving the block where it was declared. After that, it will be automatically deleted by the garbage collector (not immediately, but eventually).
Example 1:
Object a = new Object();
a = null; // afte...