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How to preserve insertion order in HashMap? [duplicate]
...p . When I iterate over the map, the data is returned in (often the same) random order. But the data was inserted in a specific order, and I need to preserve the insertion order. How can I do this?
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MySQL error: key specification without a key length
...r BLOB types such as TINYBLOB, MEDIUMBLOB, LONGBLOB, TINYTEXT, MEDIUMTEXT, and LONGTEXT that you try to make a primary key or index. With full BLOB or TEXT without the length value, MySQL is unable to guarantee the uniqueness of the column as it’s of variable and dynamic size. So, when using BLOB ...
The necessity of hiding the salt for a hash
...ifferent for each user but is readily available to us. The other product randomly generates a salt for each user and changes each time the user changes the password. The salt is then encrypted in the database.
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Custom ListView click issue on items in Android
... list of databases internally. Do I just need to get the LinearLayout view and add an onClickListener like Tom did? I'm not sure.
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Python integer division yields float
... answered Aug 15 '09 at 21:51
Brandon E TaylorBrandon E Taylor
23.1k66 gold badges4343 silver badges6868 bronze badges
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How do you match only valid roman numerals with a regular expression?
...L|L?X{0,3})(IX|IV|V?I{0,3})$
Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple:
0: <empty> matched by M{0}
1000: M matched by M{1}
2000: MM matched by M{2}
3000: MMM matched by M{3}
4000:...
How to initialize log4j properly?
...ile it used to initialize itself, which loggers / appenders got configured and how etc.
The configuration file can be a java properties file or an xml file. Here is a sample of the properties file format taken from the log4j intro documentation page:
log4j.rootLogger=debug, stdout, R
log4j.appen...
How do I use WebRequest to access an SSL encrypted site using https?
...t.com/en-us/library/ds8bxk2a.aspx
For http connections, the WebRequest and WebResponse classes use SSL to communicate with web hosts that support SSL. The decision to use SSL is made by the WebRequest class, based on the URI it is given. If the URI begins with "https:", SSL is used; if the URI b...
Are there any downsides to passing structs by value in C, rather than passing a pointer?
...ot of C programming is for embedded systems, where memory is at a premium, and stack sizes may be measured in KB or even Bytes... If you're passing or returning structs by value, copies of those structs will get placed on the stack, potentially causing the situation that this site is named after...
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Checking if a double (or float) is NaN in C++
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According to the IEEE standard, NaN values have the odd property that comparisons involving them are always false. That is, for a float f, f != f will be true only if f is NaN.
Note that, as some comments below have pointed out, not all compilers ...