38 lines
978 B
Java
38 lines
978 B
Java
// generics/InstantiateGenericType.java
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// (c)2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
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class ClassAsFactory<T> {
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T x;
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public ClassAsFactory(Class<T> kind) {
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try {
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x = kind.newInstance();
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} catch(InstantiationException |
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IllegalAccessException e) {
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throw new RuntimeException(e);
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}
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}
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}
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class Employee {}
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public class InstantiateGenericType {
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public static void main(String[] args) {
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ClassAsFactory<Employee> fe =
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new ClassAsFactory<>(Employee.class);
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System.out.println(
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"ClassAsFactory<Employee> succeeded");
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try {
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ClassAsFactory<Integer> fi =
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new ClassAsFactory<>(Integer.class);
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} catch(Exception e) {
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System.out.println("ClassAsFactory<Integer> failed");
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}
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}
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}
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/* Output:
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ClassAsFactory<Employee> succeeded
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ClassAsFactory<Integer> failed
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*/
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