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POHow can I instantiate a generic type in Java?
 

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    <p>I've added a human-readable configuration file to my app using <a href="http://download.oracle.com/javase/6/docs/api/java/util/Properties.html"><code>java.util.Properties</code></a> and am trying to add a wrapper around it to make type conversions easier. Specifically, I want the returned value to "inherit" it's type from the provided default value. Here's what I've got so far:</p> <pre class="lang-java prettyprint-override"><code>protected &lt;T&gt; T getProperty(String key, T fallback) { String value = properties.getProperty(key); if (value == null) { return fallback; } else { return new T(value); } } </code></pre> <p><a href="http://pastebin.com/CWpzFziJ">(Full example source.)</a></p> <p>The return value from <code>getProperty("foo", true)</code> would then be a boolean regardless of whether it was read from the properties file and similarly for strings, integers, doubles, &amp;c. Of course, the above snippet doesn't actually compile:</p> <pre class="lang-none prettyprint-override"><code>PropertiesExample.java:35: unexpected type found : type parameter T required: class return new T(value); ^ 1 error </code></pre> <p>Am I doing this wrong, or am I simply trying to do something which can't be done?</p> <p><strong>Edit:</strong> Usage example:</p> <pre class="lang-java prettyprint-override"><code>// I'm trying to simplify this... protected void func1() { foobar = new Integer(properties.getProperty("foobar", "210")); foobaz = new Boolean(properties.getProperty("foobaz", "true")); } // ...into this... protected void func2() { foobar = getProperty("foobar", 210); foobaz = getProperty("foobaz", true); } </code></pre>
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