33 lines
911 B
Java
33 lines
911 B
Java
// generics/GenericArray.java
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// (c)2017 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://OnJava8.com for more book information.
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public class GenericArray<T> {
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private T[] array;
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@SuppressWarnings("unchecked")
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public GenericArray(int sz) {
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array = (T[])new Object[sz];
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}
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public void put(int index, T item) {
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array[index] = item;
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}
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public T get(int index) { return array[index]; }
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// Method that exposes the underlying representation:
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public T[] rep() { return array; }
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public static void main(String[] args) {
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GenericArray<Integer> gai = new GenericArray<>(10);
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try {
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Integer[] ia = gai.rep();
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} catch(ClassCastException e) {
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System.out.println(e.getMessage());
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}
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// This is OK:
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Object[] oa = gai.rep();
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}
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}
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/* Output:
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[Ljava.lang.Object; cannot be cast to
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[Ljava.lang.Integer;
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*/
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