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<TITLE>Listing the Elements of a Collection
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<h3>
e345.
Listing the Elements of a Collection</h3>
This example demonstrates how to iterate over the elements of various
types of collections.
<pre>
// For a set or list
for (Iterator it=<font color="#0066ff"><i>collection</i></font>.iterator(); it.hasNext(); ) {
Object element = it.next();
}
// For keys of a map
for (Iterator it=<font color="#0066ff"><i>map</i></font>.keySet().iterator(); it.hasNext(); ) {
Object key = it.next();
}
// For values of a map
for (Iterator it=<font color="#0066ff"><i>map</i></font>.values().iterator(); it.hasNext(); ) {
Object value = it.next();
}
// For both the keys and values of a map
for (Iterator it=<font color="#0066ff"><i>map</i></font>.entrySet().iterator(); it.hasNext(); ) {
Map.Entry entry = (Map.Entry)it.next();
Object key = entry.getKey();
Object value = entry.getValue();
}
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Related Examples
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e342. <a class="eglink" href="coll_Queue.html?l=rel">
Implementing a Queue
</a>
<br>
e343. <a class="eglink" href="coll_Stack.html?l=rel">
Implementing a Stack
</a>
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e344. <a class="eglink" href="coll_Cache.html?l=rel">
Implementing a Least-Recently-Used (LRU) Cache
</a>
<br>
e346. <a class="eglink" href="coll_StorePrimitive.html?l=rel">
Storing Primitive Types in a Collection
</a>
<br>
e347. <a class="eglink" href="coll_CreateCopy.html?l=rel">
Creating a Copy of a Collection
</a>
<br>
e348. <a class="eglink" href="coll_MakeRo.html?l=rel">
Making a Collection Read-Only
</a>
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See also:
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Arrays">
Arrays
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Bits">
Bits
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Dates">
Dates
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Hash%20Tables">
Hash Tables
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Lists">
Lists
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Property%20Files">
Property Files
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Sets">
Sets
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Sorted%20Collections">
Sorted Collections
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Time">
Time
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Timers">
Timers
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