19 lines
533 B
Java
19 lines
533 B
Java
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// patterns/Single.java
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// (c)2021 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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@SuppressWarnings("unchecked")
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public final class Single<T> {
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private static Object single; // [1]
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public Single(T val) {
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if(single != null)
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throw new RuntimeException(
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"Attempt to reassign Single<" +
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val.getClass().getSimpleName() + ">"
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);
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single = val;
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}
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public T get() { return (T)single; }
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}
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