RejectingArrayBitSetPool implements ArrayBitSetPool { @NotNull @Override public ArrayBitSet borrowSet(final int size) { throw new UnsupportedOperationException(); } private  RejectingArrayBitSetPool(); @NotNull @Override ArrayBitSet borrowSet(final int size); @Override void returnSet(
            @NotNull
            final ArrayBitSet set); static final ArrayBitSetPool INSTANCE; }
@Test(expected = UnsupportedOperationException.class) public void rejectBorrow() { RejectingArrayBitSetPool.INSTANCE.borrowSet(1); }