大约有 7,540 项符合查询结果（耗时：0.0239秒） [XML]
The difference between fork(), vfork(), exec() and clone()
...ng processes with a huge memory footprint to run some small program (think Java's Runtime.exec()). POSIX has standardized the posix_spawn() to replace these latter two more modern uses of vfork().
posix_spawn() does the equivalent of a fork()/execve(), and also allows some fd juggling in between. It...
Database development mistakes made by application developers [closed]
... language struggles to deal with problems that are trivial in langues like Java, C#, Delphi etc.
This lack of understanding manifests itself in a few ways.
Inappropriately imposing too much procedural or imperative logic on the databse.
Inappropriate or excessive use of cursors. Especially when a...
In C#, why is String a reference type that behaves like a value type?
...(struct handling was inefficient in .NET 1.0, and it was natural to follow Java, in which strings were already defined as a reference, rather than primitive, type. Plus, if string were a value type then converting it to object would require it to be boxed, a needless inefficiency).
...
URL matrix parameters vs. query parameters
... were appended to when injecting with @MatrixParam. According to "Restful Java with JAX-RS 2.0", a request like "GET /mercedes/e55;color=black/2006/interior;color=tan" would have an ambiguous definition of the color matrix param. Although it looks like if you process each PathSegment individually ...
“Least Astonishment” and the Mutable Default Argument
... languages have this problem to some extent. Here's a question: suppose in Java I have the following code:
StringBuffer s = new StringBuffer("Hello World!");
Map<StringBuffer,Integer> counts = new HashMap<StringBuffer,Integer>();
counts.put(s, 5);
s.append("!!!!");
System.out.println( c...
Maven: how to override the dependency added by a library
....version</version>
<exclusions>
<!-- STAX comes with Java 1.6 -->
<exclusion>
<artifactId>stax-api</artifactId>
<groupId>javax.xml.stream</groupId>
</exclusion>
<exclusion>
<artifactId>stax-api<...
Android custom dropdown/popup menu
... with Kotlin refer my answer here.
To create a popup menu in android with Java:
Create a layout file activity_main.xml under res/layout directory which contains only one button.
Filename: activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:...
How to get the ThreadPoolExecutor to increase threads to max before queueing?
... ExecutorService thread-pools that so many of us use. To quote from the Javadocs:
9 Answers
...
Further understanding setRetainInstance(true)
...ethod.
And the docs link to a very good example - FragmentRetainInstance.java which I have reproduced below for your convenience. It does exactly what I speculated was the answer in my question (if (...findFragmentByTag() == null) { ...).
Finally, I created my own test activity to see exactly wha...
What is a callback function?
...this, the service providers often design APIs using the callback pattern.
JavaScript supports callbacks very nicely e.g. with lambdas and closures. And there is a lot of activity in the JavaScript world, both on the browser as well as on the server. There are even JavaScript platforms being develop...