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@@ -0,0 +1,13 @@
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+import java.util.*;
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+
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+public class TestImmutable {
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+ public static void main(String[] args) {
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+ HashMap<Integer, Integer> map = new HashMap<>();
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+ Map<Integer, Integer> immutableMap = Collections.unmodifiableMap(map);
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+ try {
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+ immutableMap.put(0, 0);
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+ } catch (Exception e) {
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+ e.printStackTrace();
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+ }
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+ }
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+}
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