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&& (AND) and || (OR) in IF statements
...uated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if (str == null || str.isEmpty()) {
complainAboutUnusableString();
} ...
What is the difference between & and && in Java?
... a short circuit operator whereas & is a AND operator.
Try this.
String s = null;
boolean b = false & s.isEmpty(); // NullPointerException
boolean sb = false && s.isEmpty(); // sb is false
shar...
PHP mail function doesn't complete sending of e-mail
...ed out.
Make sure the mail() function is called correctly
bool mail ( string $to , string $subject , string $message [, string $additional_headers [, string $additional_parameters ]] )
The mail function takes three required parameters and optionally a fourth and fifth one. If your call to mai...
LINQ: Distinct values
...e("{0,-15} {1,-15}",
row.Field<int>(0),
row.Field<string>(1));
}
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JPA eager fetch does not join
... @JoinColumn(name="messageId")
private Message message;
private String governmentId;
public MessageRecipientId() {
}
public Message getMessage() {
return message;
}
public void setMessage(Message message) {
this.message = message;
}
public S...
How do I check in SQLite whether a table exists?
... Cursor, rawQuery with parameters.
boolean tableExists(SQLiteDatabase db, String tableName)
{
if (tableName == null || db == null || !db.isOpen())
{
return false;
}
Cursor cursor = db.rawQuery("SELECT COUNT(*) FROM sqlite_master WHERE type = ? AND name = ?", new String[] {"t...
how to detect search engine bots with php?
...
Check the $_SERVER['HTTP_USER_AGENT'] for some of the strings listed here:
http://www.useragentstring.com/pages/useragentstring.php
Or more specifically for crawlers:
http://www.useragentstring.com/pages/useragentstring.php?typ=Crawler
If you want to -say- log the number of ...
Is there a limit to the length of HTML attributes?
...
I've just written a test which puts a string of length 10 million into an attribute and then retrieves it again, and it works fine (Firefox 3.5.2 & Internet Explorer 7)
50 million makes the browser hang with the "This script is taking a long time to complete...
Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
...erands are converted to numbers if
possible; else if either operand is a string, the string operand is
converted to a number if possible. If both operands are objects, then
JavaScript compares internal references which are equal when operands
refer to the same object in memory.
So what hap...
Stop caching for PHP 5.5.3 in MAMP
...n-zts-20121212/opcache.so"
opcache.memory_consumption=128
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=4000
opcache.revalidate_freq=60
opcache.fast_shutdown=1
opcache.enable_cli=1
enable=0
Must be added under [OPcache] in php.ini.
Disables OPcache.
Requires MAMP server restart.
...