Java Iterable Size countElements(Iterable pairs)

Description

count Elements

License

Apache License

Declaration

private static int countElements(Iterable<?> pairs) 

Method Source Code

//package com.java2s;
/*//from  w  w  w  . j a  v  a 2s.com
 * Copyright 2009 the original author or authors.
 * 
 * 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.
 */

import java.util.List;

public class Main {
    private static int countElements(Iterable<?> pairs) {
        // Currently we can only handle split results
        // that are lists because we need its size.
        if (pairs instanceof List) {
            return ((List<?>) pairs).size();
        } else {
            throw new IllegalArgumentException("Cannot determine split size from split result.");
        }
    }
}

Related

1. getIterableSize(Iterable iterable)
2. getSingle(Iterable it)
3. getSingleElementOrNull(Iterable coll)
4. getSingleIfExist(Iterable iterable)