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POIterator generics, cannot declare an iterator of mismatching types (maybe casting issue)
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  1. POIterator generics, cannot declare an iterator of mismatching types (maybe casting issue)
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    copied!<p>I have this simple code</p> <pre><code>public String toString() { **Iterator it = list.iterator();** String s; while(it.hasNext()){ s = s + " " + Integer.toString(it.next()); } System.out.println(s); // IMPLEMENT THIS METHOD VIA AN ITERATOR // MAKE SURE THE OUTPUT PRODUCED BY THE METHOD // DISPLAYS THE LEAST SIGNIFICANT BIT TO THE RIGHT. } </code></pre> <p>At the line with asterisks, I get the following compilation error.</p> <pre><code>Error: incompatible types required: Iterator found: java.util.Iterator&lt;java.lang.Integer&gt; </code></pre> <p>I already tried this,</p> <pre><code>**Iterator&lt;Integer&gt; it = list.iterator();** </code></pre> <p>I get, <code>Error: type Iterator does not take parameters</code></p> <p>EDIT <em>*</em></p> <p>I forgot to mention, I have my own implementation of the interface methods.</p> <pre><code>/* * Inner class to implement the iterator for the &lt;code&gt;BitList&lt;/code&gt;. */ private class BitListIterator implements Iterator { /* * A reference to the current &lt;code&gt;Node&lt;/code&gt; in the iterator. */ private Node current = null; /* * The expected modification count variable. * Needed for the "fast-fail" implementation of the iterator. */ private int expectedModCount = modCount; /* * Advances the iterator to the next element in the list. */ public int next() { checkValid(); if (current == null) { current = first ; } else { current = current.next ; // move the cursor forward } if (current == null) throw new NoSuchElementException() ; return current.value ; } /** * Inserts a new &lt;code&gt;int&lt;/code&gt; value immediately before the next element that would be returned by &lt;code&gt;next()&lt;/code&gt;. */ public void add(int newElement) { Node newNode; if (current == null) { first = new Node(newElement, first); current = first; } else { current.next = new Node(newElement, current.next); current = current.next; } modCount++ ; expectedModCount++ ; } /** * Indicates whether there is a next element in the list being traversed or not. */ public boolean hasNext() { return ((current == null) &amp;&amp; (first != null)) || ((current != null) &amp;&amp; (current.next !=null)); } /** * Checks whether this iterator remains valid, i.e. no concurrent modifications have been made on the list. */ private void checkValid() { if (expectedModCount != modCount) throw new ConcurrentModificationException(); } } // end of BitListIterator class </code></pre> <p>So if import the package I get the following errors</p> <pre><code>Error: BitList.BitListIterator is not abstract and does not override abstract method remove() in java.util.Iterator Error: next() in BitList.BitListIterator cannot implement next() in java.util.Iterator return type int is not compatible with java.lang.Object </code></pre> <p>I have jdk 1.7 and its in use.</p> <p>Any ideas would certainly help.</p> <p>Thank you,</p> <p>Mjall2</p>
 

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