Returning and instance of a Class given its .class (MyClass.class)
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by jax
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Published on 2010-05-26T07:40:41Z
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java
I have an enum that will hold my algorithms. I cannot instantiate these classes because I need the application context which is only available once the application has started. I want to load the class at runtime when I choose by calling getAlgorithm(Context cnx).
How do I easily instantiate a class at runtime given its .class (and my constructor takes arguments)? All my classes are subclasses of Algorithm.
public enum AlgorithmTypes {
ALL_FROM_9_AND_LAST_FROM_10_ID(AlgorithmFactory.AlgorithmAllFrom9AndLastFrom10Impl.class),
ALL_FROM_9_AND_LAST_FROM_10_CURRENCY_ID(AlgorithmFactory.AlgorithmAllFrom9AndLastFrom10Impl.class),
DIVIDE_BY_9_LESS_THAN_100(AlgorithmFactory.AlgorithmAllFrom9AndLastFrom10Impl.class),
TABLES_BEYOND_5_BY_5(AlgorithmFactory.AlgorithmAllFrom9AndLastFrom10Impl.class);
private Class<? extends Algorithm> algorithm;
AlgorithmTypes(Class<? extends Algorithm> c) {
algorithm = c;
}
public Algorithm getAlgorithm(Context cnx) {
return //needs to return the current algoriths constructor which takes the Context Algorithm(Context cnx);
}
}
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