Java List Concatenate concat(Collection> lists)

Description

Concatenate the collection of lists passed as argument into a new array list.

License

Apache License

Parameter

Parameter	Description
lists	a parameter
T	a parameter

Declaration

public static <T> List<T> concat(Collection<? extends Collection<T>> lists) 

Method Source Code

//package com.java2s;
/**//from   w w  w  . ja va  2 s .  co  m
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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.ArrayList;
import java.util.Collection;

import java.util.List;

public class Main {
    /**
     * Concatenate the collection of lists passed as argument into a new array list.
     * @param lists
     * @param <T>
     * @return
     */
    public static <T> List<T> concat(Collection<? extends Collection<T>> lists) {
        int size = 0;
        for (Collection<T> list : lists) {
            size += list.size();
        }
        List<T> result = new ArrayList<T>(size);
        for (Collection<T> list : lists) {
            result.addAll(list);
        }
        return result;
    }
}

Related

1. ByteConcatenator(List instructionbytes, int num)
2. concat(Collection list1, Collection list2)
3. concat(final byte[] result, final List buffers)
4. concat(final Collection... lists)
5. concat(final List list1, final List list2)