More About Arrays

• If you know the values of an array ahead of time, you can assign them to the array when you declare the array.
• Just put the values in curly braces after the =.  Separate the values with commas.  Example:

String[] sanderLabs = {"L203", "L206", "L209", "L221", "L222"};
• You can even assign this new array to an old array, and the size of the array will dynamically change to reflect the size of the new array.
• Example:

names = sanderLabs;
• At this point, names no longer has the size 34, but 5 instead.
• Just make sure the types are the same.
• A more sophisticated copy:
• You can copy elements from a specified position in one array to a specified position in another.
• Since arrays are not objects, per se, you have to use a System method.
• System.arrayCopy(from, fromIndex, to, toIndex, count);
• Where:
• from is the from array.
• fromIndex is the first element to copy.
• to is the to array.
• toIndex is the position to which to copy the elements.
• count is the number of elements to copy.
• Example: To copy the middle three rooms from sanderLabs to names, starting with the fifth element in names:

System.arraycopy(sanderLabs, 1, names, 4, 3);


 Even More About Arrays
 

Created by:  Brandan Jones January 4, 2002