There are many ways to create a fixed list in Java, one of them is by using the FixedSizeList class, found in the Apache org.apache.commons.collections package (http://commons.apache.org/collections/). FixedSizeList does not support the add, remove, clear and retain methods and the set method is allowed as far as it doesn’t change the list size:
And the output is:
package fixedsizelist.exemple;
import java.util.Arrays;
import java.util.List;
import org.apache.commons.collections.list.FixedSizeList;
public class FixedSizeListExemple {
public static void main(String[] args) {
List fixedList = FixedSizeList.decorate(Arrays.asList(new String[5]));
fixedList.set(0, "some_name@yahoo.com");
fixedList.set(1, "some_other_name@gmail.com");
fixedList.set(2, "777_name@rocketmail.com");
fixedList.set(3, "bond_007@yahoo.com");
fixedList.set(4, "james99@yahoo.com");
System.out.println("\tDisplay list values...\n");
for (String obj : fixedList) {
System.out.println(obj.toString());
}
try {
System.out.println("\n\tTrying to modify our fixed list...\n");
fixedList.add("paul01_mac@yahoo.com");
fixedList.remove(3);
fixedList.clear();
} catch (Exception e) {
System.out.println
(" The add, remove, clear and retain operations are unsupported."
+ "\nThe set method is allowed (as it doesn't change the list size).\n");
}
}
}
And the output is:
No comments:
Post a Comment