System.arraycopy()

Although copying an array isn't particularly difficult, it is an operation which benefits from a native implementation. Therefore java.lang.System includes a static System.arraycopy() method you can use to copy one array to another.

public static void arraycopy(Object source, int sourcePosition, 
 Object destination, int destinationPosition, int numberOfElements)

System.arraycopy() copies numberOfElements elements from the array source, beginning with the element at sourcePosition, to the array destination starting at destinationPosition. The destination array must already exist when System.arraycopy() is called. The method does not create it. The source and destination arrays must be of the same type.

For example,

 int[] unicode = new int[65536];
  for (int i = 0; i < unicode.length; i++) {
    unicode[i] = i;
  }
  int[] latin1 = new int[256];
  System.arraycopy(unicode, 0, latin1, 0, 256);

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Copyright 1997-1999, 2005 Elliotte Rusty Harold
elharo@metalab.unc.edu
Last Modified February 3, 2005