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Lock, mutex, semaphore… what's the difference?
I've heard these words related to concurrent programming, but what's the difference between them?
9 Answers
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How can I export the schema of a database in PostgreSQL?
..._dump -s databasename
Will dump only the schema to stdout as .sql.
For windows, you'll probably want to call pg_dump.exe. I don't have access to a Windows machine but I'm pretty sure from memory that's the command. See if the help works for you too.
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Integrating the ZXing library directly into my Android application
I'm writing this in mere desperation :) I've been assigned to make a standalone barcode scanner (as a proof of concept) to an Android 1.6 phone.
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Base64 encoding in SQL Server 2005 T-SQL
I'd like to write a T-SQL query where I encode a string as a Base64 string. Surprisingly, I can't find any native T-SQL functions for doing Base64 encoding. Does a native function exist? If not, what's the best way to do Base64 encoding in T-SQL?
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Java: recommended solution for deep cloning/copying an instance
I'm wondering if there is a recommended way of doing deep clone/copy of instance in java.
9 Answers
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Why Doesn't C# Allow Static Methods to Implement an Interface?
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Assuming you are asking why you can't do this:
public interface IFoo {
void Bar();
}
public class Foo: IFoo {
public static void Bar() {}
}
This doesn't make sense to me, semantically. Methods specified on an interfac...
Renew Provisioning Profile
Just got a notice that the provisioning profile for one of my apps is about to expire. Is there some way I can renew the existing one or must I recreate a new one?
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Why is 128==128 false but 127==127 is true when comparing Integer wrappers in Java?
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When you compile a number literal in Java and assign it to a Integer (capital I) the compiler emits:
Integer b2 =Integer.valueOf(127)
This line of code is also generated when you use autoboxing.
valueOf is implemented such that certain numbers are "pooled...
How to refresh app upon shaking the device?
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Here is an example code.
Put this into your activity class:
/* put this into your activity class */
private SensorManager mSensorManager;
private float mAccel; // acceleration apart from gravity
private float mAccelCurrent; // current acceleration in...
How to invoke the super constructor in Python?
In all other languages I've worked with the super constructor is invoked implicitly. How does one invoke it in Python? I would expect super(self) but this doesn't work.
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