Create a typesafe copy of a raw list. : Generic Collection « Generics « Java

Create a typesafe copy of a raw list.

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import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.RandomAccess;

 * @since 4.37
 * @author Jaroslav Tulach

public class Utils {

   * Create a typesafe copy of a raw list.
   * @param rawList an unchecked list
   * @param type the desired supertype of the entries
   * @param strict true to throw a <code>ClassCastException</code> if the raw list has an invalid entry,
   *               false to skip over such entries (warnings may be logged)
   * @return a typed list guaranteed to contain only entries assignable
   *         to the named type (or they may be null)
   * @throws ClassCastException if some entry in the raw list was not well-typed, and only if <code>strict</code> was true
  public static <E> List<E> checkedListByCopy(List rawList, Class<E> type, boolean strict) throws ClassCastException {
      List<E> l = (rawList instanceof RandomAccess) ? new ArrayList<E>(rawList.size()) : new LinkedList<E>();
      Iterator it = rawList.iterator();
      while (it.hasNext()) {
          Object e =;
          try {
          } catch (ClassCastException x) {
              if (strict) {
                  throw x;
              } else {
                  System.out.println("not assignable ");
      return l;


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