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<TITLE>Associating a Value with an Object
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<h3>
e337.
Associating a Value with an Object</h3>
This example demonstrates how to associate a value with an arbitrary
object. The technique involves saving the object and the associated
value as a key/value pair in an <code>IdentityHashMap</code>. A <code>HashMap</code>
cannot be used for this purpose since if two objects happen to equal
via the <code>Object.equals()</code> method, one of the objects will not be
stored.
<pre>
// Create the map
Map objMap = new IdentityHashMap();
// Add the object and value pair to the map
Object o1 = <font color="#0066ff"><i>new Integer(123)</i></font>;
Object o2 = <font color="#0066ff"><i>new Integer(123)</i></font>;
objMap.put(o1, <font color="#0066ff"><i>"first"</i></font>);
objMap.put(o2, <font color="#0066ff"><i>"second"</i></font>);
// Retrieve the value associated with the objects
Object v1 = objMap.get(o1); // first
Object v2 = objMap.get(o2); // second
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Related Examples
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e331. <a class="eglink" href="GenRandom.html?l=rel">
Generating a Random Number
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e332. <a class="eglink" href="ParseString.html?l=rel">
Breaking a String into Words
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e333. <a class="eglink" href="CustEvent.html?l=rel">
Creating a Custom Event
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e334. <a class="eglink" href="Obs.html?l=rel">
Implementing a Simple Event Notifier
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e335. <a class="eglink" href="GetAllLocales.html?l=rel">
Listing All Available Locales
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e336. <a class="eglink" href="SetDefLocale.html?l=rel">
Setting the Default Locale
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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
</a>
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Collections">
Collections
</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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