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<TITLE>Creating a Copy of a Collection
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<h3>
e347.
Creating a Copy of a Collection</h3>
These examples create a shallow copy of a collection. That is, the
new collection contains references to same objects as the source
collection; the objects are not cloned.
<pre>
List stuff = Arrays.asList(new String[]{<font color="#0066ff"><i>"a"</i></font>, <font color="#0066ff"><i>"b"</i></font>});
// Make a copy of a list
List list = new ArrayList(stuff);
List list2 = new LinkedList(list);
// Make a copy of a set
Set set = new HashSet(stuff);
Set set2 = new TreeSet(set);
// Make a copy of a map
Map map = new HashMap();
// Add key/value pairs ...
Map map2 = new TreeMap(map);
</pre>
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Related Examples
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e342. <a class="eglink" href="coll_Queue.html?l=rel">
Implementing a Queue
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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>
e345. <a class="eglink" href="coll_Iterate.html?l=rel">
Listing the Elements of a Collection
</a>
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e346. <a class="eglink" href="coll_StorePrimitive.html?l=rel">
Storing Primitive Types in a Collection
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e348. <a class="eglink" href="coll_MakeRo.html?l=rel">
Making a Collection Read-Only
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See also:
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Arrays">
Arrays
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<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Bits">
Bits
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<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Dates">
Dates
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<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
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<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Property%20Files">
Property Files
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<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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