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 * 2 along with this work; if not, write to the Free Software Foundation,
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/**
 * @test
 * @bug 8072726
 * @summary Tests for Enumeration-to-Iterator conversion.
 * @run testng EnumerationAsIterator
 */

import java.util.*;

import org.testng.annotations.Test;
import static org.testng.Assert.*;

@Test
public class EnumerationAsIterator {
    public void emptyHasNext() {
        Iterator<Object> it = Collections.emptyEnumeration().asIterator();
        assertFalse(it.hasNext());
    }

    @Test(expectedExceptions = {NoSuchElementException.class})
    public void emptyNextThrows() {
        Iterator<Object> it = Collections.emptyEnumeration().asIterator();
        Object o = it.next();
        fail("NoSuchElementException should have been thrown");
    }

    private List<String> copy(List<String> input) {
        List<String> output = new ArrayList<>();
        Collections.enumeration(input)
                   .asIterator()
                   .forEachRemaining(output::add);
        return output;
    }

    public void copyZero() {
        assertEquals(copy(Collections.emptyList()), Collections.emptyList());
    }

    public void copyOne() {
        assertEquals(copy(Collections.singletonList("a")),
                          Collections.singletonList("a"));
    }

    public void copyMany() {
        List<String> input = Arrays.asList("a", "b", "c");
        assertEquals(copy(input), input);
    }

    public void repeatedCalls() {
        Iterator<String> iter = new Vector<>(Arrays.asList("a", "b", "c"))
            .elements().asIterator();
        assertTrue(iter.hasNext());
        assertTrue(iter.hasNext());
        assertEquals(iter.next(), "a");
        assertEquals(iter.next(), "b");
        assertEquals(iter.next(), "c");
        assertFalse(iter.hasNext());
        assertFalse(iter.hasNext());
    }
}