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What are the differences between a HashMap and a Hashtable in Java?
...ntly synchronised HashMap can be obtained by:
Collections.synchronizedMap(myMap);
But to correctly implement this logic you need additional synchronisation of the form:
synchronized(myMap) {
if (!myMap.containsKey("tomato"))
myMap.put("tomato", "red");
}
Even iterating over a Hasht...
Where are static variables stored in C and C++?
... edited Feb 26 at 22:11
Tommy
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answered Sep 18 '08 at 15:07
...
What's the strangest corner case you've seen in C# or .NET? [closed]
...where T : class, new():
private static void Main() {
CanThisHappen<MyFunnyType>();
}
public static void CanThisHappen<T>() where T : class, new() {
var instance = new T(); // new() on a ref-type; should be non-null, then
Debug.Assert(instance != null, "How did we break the ...
Make a link use POST instead of GET
...don't want to install anything more than you already have.
<form name="myform" action="handle-data.php" method="post">
<label for="query">Search:</label>
<input type="text" name="query" id="query"/>
<button>Search</button>
</form>
<script>
var ...
How do I send a POST request with PHP?
...is version uses curl library and I think is most "universal" so I give you my vote
– Dayron Gallardo
Aug 26 '14 at 11:42
...
Matplotlib - global legend and title aside subplots
...nd it finds the labels in each of the lines. I have had better luck making my own legend as below. Seems to work in all cases where have never seemed to get the other way going properly. If you don't understand let me know:
legendLabels = []
for i in range(modSize):
legendLabels.append(ax.plot(...
How do I create a Java string from the contents of a file?
...test.txt", Charset.defaultCharset());
Note: This answer largely replaces my Java 6 version. The utility of Java 7 safely simplifies the code, and the old answer, which used a mapped byte buffer, prevented the file that was read from being deleted until the mapped buffer was garbage collected. You ...
Why would anybody use C over C++? [closed]
...e code that executes faster than that of an inexperienced C developer.
In my industry, video games, we write high performance code in C++ by avoiding things such as RTTI, exceptions, or virtual-functions in inner loops. These can be extremely useful but have performance or bloat problems that it's ...
In jQuery, how do I get the value of a radio button when they all have the same name?
Here is my code:
7 Answers
7
...
Is there any difference between GROUP BY and DISTINCT
...as been mentioned by many other answers), the most important difference in my opinion is the fact that the two operations "happen" at two very different steps in the logical order of operations that are executed in a SELECT statement.
Here are the most important operations:
FROM (including JOIN,...