/*
    * Copyright (C) 2010 The Guava Authors
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.google.common.collect;
  
  import com.google.common.annotations.GwtCompatible;
  
  import junit.framework.TestCase;
  
  import java.util.Iterator;
  import java.util.ListIterator;
  import java.util.NoSuchElementException;
  
  /**
   * Tests for UnmodifiableListIterator.
   * 
   * @author Louis Wasserman
   */
  @GwtCompatible
  public class UnmodifiableListIteratorTest extends TestCase {
    public void testRemove() {
      Iterator<String> iterator = create();
  
      assertTrue(iterator.hasNext());
      assertEquals("a", iterator.next());
      try {
        iterator.remove();
        fail();
      } catch (UnsupportedOperationException expected) {}
    }
    
    public void testAdd() {
      ListIterator<String> iterator = create();
  
      assertTrue(iterator.hasNext());
      assertEquals("a", iterator.next());
      assertEquals("b", iterator.next());
      assertEquals("b", iterator.previous());
      try {
        iterator.add("c");
        fail();
      } catch (UnsupportedOperationException expected) {}
    }
    
    public void testSet() {
      ListIterator<String> iterator = create();
  
      assertTrue(iterator.hasNext());
      assertEquals("a", iterator.next());
      assertEquals("b", iterator.next());
      assertEquals("b", iterator.previous());
      try {
        iterator.set("c");
        fail();
      } catch (UnsupportedOperationException expected) {}
    }
  
    UnmodifiableListIterator<String> create() {
      final String[] array = {"a", "b", "c"};
  
      return new UnmodifiableListIterator<String>() {
        int i;
        @Override
        public boolean hasNext() {
          return i < array.length;
        }
        @Override
        public String next() {
          if (!hasNext()) {
            throw new NoSuchElementException();
          }
          return array[i++];
        }
        @Override public boolean hasPrevious() {
          return i > 0;
        }
        @Override public int nextIndex() {
          return i;
        }
        @Override public String previous() {
          if (!hasPrevious()) {
            throw new NoSuchElementException();
          }
          return array[--i];
        }
        @Override public int previousIndex() {
         return i-1;
       }
     };
   }
 }