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Weird Integer boxing in Java
...ion code is handled by the compiler.
So during compilation phase compiler converts Integer a = 1000, b = 1000; to Integer a = Integer.valueOf(1000), b = Integer.valueOf(1000);.
So it is Integer.valueOf() method which actually gives us the integer objects, and if we look at the source code of Integ...
Improving bulk insert performance in Entity framework [duplicate]
... {
var e = entity;
table.Rows.Add(properties.Select(property => GetPropertyValue(property.GetValue(e, null))).ToArray());
}
// send it to the server for bulk execution
bulkCopy.BulkCopyTimeout = 5 * 60;
bulkCopy.WriteToServer(table);
...
Can a CSV file have a comment?
...g else"
1,2
Pay close attention at the 'quotes' in the first line.
When converting your text to columns using the Excel wizard, remember checking the 'Treat consecutive delimiters as one', setting it to use 'quotes' as delimiter.
Thus, Excel will split the text at the commas, keeping the 'commen...
How to print a dictionary line by line in Python?
...
You could use the json module for this. The dumps function in this module converts a JSON object into a properly formatted string which you can then print.
import json
cars = {'A':{'speed':70, 'color':2},
'B':{'speed':60, 'color':3}}
print(json.dumps(cars, indent = 4))
The output looks...
How do I create a copy of an object in PHP?
...what you intend to do, it does it in an awfully slow way. Not only are you converting all your object into a string and back, using time and memory, you also break PHPs possible CopyOnWrite mechanism. A much better way is to implement your __clone method properly as suggested by stackoverflow.com/a/...
How to get a key in a JavaScript object by its value?
...
I think Converting it to a string would be better to fix type errors just add .toString() like obj[ key ].toString() and to the value if desired...
– CrandellWS
Jan 6 '15 at 20:19
...
Detecting Browser Autofill
...e change event.
Firefox 4 does dispatch the change change event when users select a value from a list of suggestions and tab out of the field.
Chrome 9 does not dispatch the change event.
Safari 5 does dispatch the change event.
You best options are to either disable autocomplete for a form usin...
Comparing two dataframes and getting the differences
... lists, to do it efficiently we should first order them then compare them (converting the list to sets/hashing would also be fast; both are an incredible improvement to the simple O(N^2) double comparison loop
Note: the following code produces the tables:
df1=pd.DataFrame({
'Date':['2013-11-24...
Jackson Vs. Gson [closed]
...ns of Gson also include streaming reader
Tree model (DOM-like access); can convert between various models (tree <-> java object <-> stream)
Can use any constructors (or static factory methods), not just default constructor
Field and getter/setter access (earlier gson versions only used f...
Why should I use Deque over Stack?
...reason to use Dequeue over Stack is Dequeue has the ability to use streams convert to list with keeping LIFO concept applied while Stack does not.
Stack<Integer> stack = new Stack<>();
Deque<Integer> deque = new ArrayDeque<>();
stack.push(1);//1 is the top
deque.push(1)//1 ...