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What does the question mark in Java generics' type parameter mean?
This is a small snippet of code taken from some of the examples that accompany the Stanford Parser. I've been developing in Java for about 4 years, but have never had a very strong understanding of what this style of code is supposed to indicate.
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Why does int num = Integer.getInteger(“123”) throw NullPointerException?
...t do what you think it does
It returns null in this case
the assignment from Integer to int causes auto-unboxing
Since the Integer is null, NullPointerException is thrown
To parse (String) "123" to (int) 123, you can use e.g. int Integer.parseInt(String).
References
Java Language Guide/Au...
Add default value of datetime field in SQL Server to a timestamp
I've got a table that collects forms submitted from our website, but for some reason, when they created the table, they didn't put a timestamp in the table. I want it to enter the exact date and time that the record was entered.
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How to programmatically click a button in WPF?
... />, the event will be caught by the on click handler as per normal. +1 from me!
– metao
Jun 3 '10 at 3:59
4
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Multiple Inheritance in C#
...tract base class that implements both IFirst and ISecond, and then inherit from just that base.
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Convert string to Python class object?
...cation of using eval. You better make sure the string you passed in is not from user.
– Overclocked
Jul 18 '13 at 13:32
18
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APT command line interface-like yes/no input?
...t() (or simply input() for Python 3). There is no built-in way to do this. From Recipe 577058:
import sys
def query_yes_no(question, default="yes"):
"""Ask a yes/no question via raw_input() and return their answer.
"question" is a string that is presented to the user.
"default" is the...
What is the concept of erasure in generics in Java?
...ns that the type information which is present in the source code is erased from the compiled bytecode. Let us understand this with some code.
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class GenericsErasure {
public static void main(String args[]) {
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How do I create a copy of an object in PHP?
...e same object without being references to the same value. This can be seen from this example: $a = new stdClass; $b =& $a; $a = 42; var_export($b); here $b is a reference to the variable $a; if you replace =& with a normal =, it is not a reference, and still points to the original object.
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Difference between using bean id and name in Spring configuration file
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From the Spring reference, 3.2.3.1 Naming Beans:
Every bean has one or more ids (also
called identifiers, or names; these
terms refer to the same thing). These
ids must be unique within the
container the bean is h...