大约有 45,043 项符合查询结果（耗时：0.0245秒） [XML]
Design by contract using assertions or exceptions? [closed]
When programming by contract a function or method first checks whether its preconditions are fulfilled, before starting to work on its responsibilities, right? The two most prominent ways to do these checks are by assert and by exception .
...
performSelector may cause a leak because its selector is unknown
...
Solution
The compiler is warning about this for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:...
What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
It seems that many projects slowly come upon a need to do matrix math, and fall into the trap of first building some vector classes and slowly adding in functionality until they get caught building a half-assed custom linear algebra library, and depending on it.
...
Should a retrieval method return 'null' or throw an exception when it can't produce the return value
...sing java language,I have a method that is supposed to return an object if it is found.
36 Answers
...
Explicitly calling return in a function or not
... Urbanek from the R core team (I believe) for recommending a user to explicitly calling return at the end of a function (his comment was deleted though):
...
What is the difference between lower bound and tight bound?
With the reference of this answer , what is Theta (tight bound)?
8 Answers
8
...
Is a Java string really immutable?
...
String is immutable* but this only means you cannot change it using its public API.
What you are doing here is circumventing the normal API, using reflection. The same way, you can change the values of enums, change the lookup table used in Integer autoboxing etc.
Now, the reason ...
How to use Elasticsearch with MongoDB?
I have gone through many blogs and sites about configuring Elasticsearch for MongoDB to index Collections in MongoDB but none of them were straightforward.
...
Manually adding a Userscript to Google Chrome
...tead of "installing" User-Scripts I found many tutorials on the web to add it manually. All of them told me to do the same steps:
...
Comparison of Android networking libraries: OkHTTP, Retrofit, and Volley [closed]
...can provide some concrete examples of best use cases for each.
Use Retrofit if you are communicating with a Web service. Use the peer library Picasso if you are downloading images. Use OkHTTP if you need to do HTTP operations that lie outside of Retrofit/Picasso.
Volley roughly competes with Retr...