ScalaUtils.java

/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.facebook.presto.spark.classloader_interface;

import java.util.ArrayList;
import java.util.List;
import java.util.NoSuchElementException;

import static java.util.Collections.unmodifiableList;

public class ScalaUtils
{
    private ScalaUtils() {}

    public static <T> List<T> collectScalaIterator(scala.collection.Iterator<T> iterator)
    {
        List<T> result = new ArrayList<>();
        while (iterator.hasNext()) {
            result.add(iterator.next());
        }
        return unmodifiableList(result);
    }

    public static <T> scala.collection.Iterator<T> emptyScalaIterator()
    {
        return new scala.collection.AbstractIterator<T>()
        {
            @Override
            public boolean hasNext()
            {
                return false;
            }

            @Override
            public T next()
            {
                throw new NoSuchElementException();
            }
        };
    }
}