equivalent to push or pop for arrays

Question

I am trying to add  remove and reference items from an array I create in my main java file  but I am having trouble figuring out the correct syntax   In actionscript they have push   and pop   for adding and removing items in an array  is there an equivalent in android

User · Answer

Use Array list http   developer android com reference java util ArrayList html

User · Answer

You can use LinkedList  It has methods peek  poll and offer

User · Answer

You can use Arrays copyOf   with a little reflection to make a nice helper function   public class ArrayHelper       public static  lt T gt  T   push T   arr  T item            T   tmp   Arrays copyOf arr  arr length   1           tmp tmp length - 1    item          return tmp             public static  lt T gt  T   pop T   arr            T   tmp   Arrays copyOf arr  arr length - 1           return tmp            Usage   String   items   new String    a    b    c     items   ArrayHelper push items   d    items   ArrayHelper push items   e     items   ArrayHelper pop items     Results     Original  a b c      Array after push calls  a b c d e      Array after pop call  a b c d

User · Answer

For those who don t have time to refactor the code to replace arrays with Collections  for example ArrayList   there is an alternative  Unlike Collections  the length of an array cannot be changed  but the array can be replaced  like this   array   push array  item     The drawbacks are that   the whole array has to be copied each time you push  and the original array Object is not changed  so you have to update the variable s  as appropriate    Here is the push method for String   You can create multiple push methods  one for String  one for int  etc   private static String   push String   array  String push        String   longer   new String array length   1       for  int i   0  i  lt  array length  i            longer i    array i       longer array length    push      return longer      This alternative is more efficient  shorter  amp  harder to read   private static String   push String   array  String push        String   longer   new String array length   1       System arraycopy array  0  longer  0  array length       longer array length    push      return longer

User · Answer

In Java an array has a fixed size  after initialisation   meaning that you can t add or remove items from an array    int   i   new int 10     The above snippet mean that the array of integers has a length of 10  It s not possible add an eleventh integer  without re-assign the reference to a new array  like the following    int   i   new int 11     In Java the package java util contains all kinds of data structures that can handle adding and removing items from array-like collections  The classic data structure Stack has methods for push and pop

[java] equivalent to push() or pop() for arrays?

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