capacity

Possible Duplicate: How to get the capacity of the ArrayList in Java? How to find the capacity of an ArrayList ? I'm curious, what do you need it for? You should know that the capacity is not (as it may sound) an upper limit of how much you can put into the ArrayList . It's a value representing how much data you can put into the list, without forcing it to reallocate it internal array. Basically, the notion of capacity is only there in order for you to tweak the performance slightly. Anyway, perhaps you already know that, so here comes the actual answer. The interface provided by API for

I am putting together a REST API and as I'm unsure how it will scale or what the demand for it will be, I'd like to be able to rate limit uses of it as well as to be able to temporarily refuse requests when the box is over capacity or if there is some kind of slashdotted scenario. I'd also like to be able to gracefully bring the service down temporarily (while giving clients results that indicate the main service is offline for a bit) when/if I need to scale the service by adding more capacity. Are there any best practices for this kind of thing? Implementation is Rails with mysql. temoto This

When I have an empty StringBuilder with a capacity of 5 and I write "hello, world!" to it, does the C# standard specify the new capacity of the StringBuilder ? I have a vague memory that it's twice the new string's length (to avoid changing the capacity with every new appended string). Hans Passant Depends what version of .NET you're talking about. Prior to .NET 4, StringBuilder used the standard .NET strategy , doubling the capacity of the internal buffer every time it needs to be enlarged. StringBuilder was completely rewritten for .NET 4, now using ropes . Extending the allocation is now

Does vector::operator= change vector capacity? If so, how? Does vector's copy constructor copy capacity? I looked through documentation but could not find a specific answer. Is it implementation dependent? All you're guaranteed is that: The vector has enough capacity to store its elements. (Obviously.) The vector won't get a new capacity until it's current capacity is full.* So how much extra or little an implementation wants to put is up to the implementation. I think most will make capacity match size, when copying, but it cannot lower capacity. (Because of number 2 above; reallocating while

I instantiate an std::vector foo(1000) . foo.size() is now 1000 and foo.capacity() is also 1000. If I clear the vector with foo.clear() , the size() is now 0, but what is the capacity() ? Does the standard say anything about that? Armen Tsirunyan No, it doesn't. The capacity of a vector never decreases. That isn't mandated by the standard but it's so both in standard library implementations of VC++ and g++. In order to set the capacity just enough to fit the size, use the famous swap trick vector<T>().swap(foo); In C++11 standard, you can do it more explicitly: foo.shrink_to_fit(); To clear a

I noticed that the capacity method returns StringBuilder capacity without a logic way ... sometime its value is equals to the string length other time it's greater... is there an equation for know which is its logic? When you append to the StringBuilder , the following logic happens: if (newCount > value.length) { expandCapacity(newCount); } where newCount is the number of characters needed, and value.length is the current size of the buffer. expandCapacity simply increases the size of the backing char[] The ensureCapacity() method is the public way to call expandCapacity() , and its docs say:

Does anyone have advice on how to best initialize an NSMutableArray when it comes to dictating the capacity? The documentation mentions that "...even though you specify a size when you create an array, the specified size is regarded as a “hint”; the actual size of the array is still 0." So... 1) If I init with a greater capacity than I typically use, do I not have to worry about wasted memory? 2) If I init with a capacity typically lower than what I use, do I have to worry about heavier processing time allocating more memory to hold the extra elements? Just how impacting is this initialized

I am creating an app using the Bespin editor and HTML5's localStorage. It stores all files locally and helps with grammar, uses JSLint and some other parsers for CSS and HTML to aid the user. I want to calculate how much of the localStorage limit has been used and how much there actually is. Is this possible today? I was thinking for not to simply calculate the bits that are stored. But then again I'm not sure what more is there that I can't measure myself. You may be able to get an approximate idea by using the JSON methods to turn the whole localStorage object to a JSON string: JSON