The page I am working on has a javascript function executed to print parts of the page. For some reason, printing in Safari, causes the window to somehow update. I say somehow, because it does not really refresh as in reload the page, but rather it starts the "rendering" of the page from start, i.e. scroll to top, flash animations start from 0, and so forth. The effect is reproduced by this fiddle: http://jsfiddle.net/fYmnB/ Clicking the print button and finishing or cancelling a print in Safari causes the screen to "go white" for a sec, which in my real website manifests itself as something "like" a reload. While running print button with, let's say, Firefox, just opens and closes the print dialogue without affecting the fiddle page in any way. Is there something with my way of calling the browsers print method that causes this, or how can it be explained - and preferably, avoided? P.S.: On my real site the same occurs with Chrome. In the ex
You should use ArrayList instead of Vector. Vector used internal synchronisation, but that is rarely good enough for actual consistency, and only slows down execution when it is not really needed.
ReplyDeleteAlso see this stackoverflow question.
You can use an ArrayList instead.
ReplyDeleteIf you need a synchronized version, you can do something like:
ArrayList arrayList = new ArrayList();
List synchList = Collections.synchronizedList(arrayList);
ArrayList is now the better class to use. Vector is now considered Legacy, and has the added performance overhead of being Thread-Safe.
ReplyDeleteVector is a legacy collection class from Java 1.0. In Java 1.2 (long ago!), the Collections Framework was added which included new collection classes such as ArrayList and HashMap, which were intended to replace the legacy classes Vector and Hashtable.
ReplyDeleteAs said before, the legacy collection classes had built-in synchronization, which is unnecessary for many applications. Synchronization has a performance overhead, so if it's not necessary, you shouldn't use it.
In some cases (when your program is multi-threaded, and multiple threads access the same data) you need to synchronize your collections. Some people would then use the old Vector or Hashtable classes, but a better way is to use a synchronization wrapper with for example an ArrayList:
// Your standard, unsynchronized list
List<String> data = new ArrayList<String>();
// Use this to put it into a synchronization wrapper
List<String> syncedData = Collections.synchronizedList(data);
See the API documentation of Collections.synchronizedList() (and other methods) for more information.
Use ArrayList when you need a List implementation but don't need thread safety, and use CopyOnWriteArrayList when you need a List implementation that is thread safe.
ReplyDelete