Java Collection Join join(Collection collection, String separator)

Description

Joins a collection of Objects separated by a specified separator

License

Open Source License

Parameter

Parameter	Description
collection	a parameter
separator	a parameter

Return

the joined String

Declaration

public static String join(Collection<? extends Object> collection, String separator) 

Method Source Code

//package com.java2s;
/**/*from   ww w  .  j  ava 2 s  .  c om*/
 * Copyright (c) 2013 M. Alexander Nugent Consulting <i@alexnugent.name>
 *
 * M. Alexander Nugent Consulting Research License Agreement
 * Non-Commercial Academic Use Only
 *
 * This Software is proprietary. By installing, copying, or otherwise using this
 * Software, you agree to be bound by the terms of this license. If you do not agree,
 * do not install, copy, or use the Software. The Software is protected by copyright
 * and other intellectual property laws.
 *
 * You may use the Software for non-commercial academic purpose, subject to the following
 * restrictions. You may copy and use the Software for peer-review and methods verification
 * only. You may not create derivative works of the Software. You may not use or distribute
 * the Software or any derivative works in any form for commercial or non-commercial purposes.
 *
 * Violators will be prosecuted to the full extent of the law.
 *
 * All rights reserved. No warranty, explicit or implicit, provided.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARR?ANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

import java.util.Collection;

import java.util.Iterator;

public class Main {
    /**
     * Joins a collection of Objects separated by a specified separator
     * 
     * @param collection
     * @param separator
     * @return the joined String
     */
    public static String join(Collection<? extends Object> collection, String separator) {

        if (collection == null) {
            return null;
        }
        Iterator iterator = collection.iterator();
        // handle null, zero and one elements before building a buffer
        if (iterator == null) {
            return null;
        }
        if (!iterator.hasNext()) {
            return "";
        }
        Object first = iterator.next();
        if (!iterator.hasNext()) {
            return first == null ? "" : first.toString();
        }

        // two or more elements
        StringBuffer buf = new StringBuffer(256); // Java default is 16, probably too small
        if (first != null) {
            buf.append(first);
        }

        while (iterator.hasNext()) {
            if (separator != null) {
                buf.append(separator);
            }
            Object obj = iterator.next();
            if (obj != null) {
                buf.append(obj);
            }
        }
        return buf.toString();

    }
}

Related

1. join(Collection strings, String separator)
2. join(Collection tokens, String separator)
3. join(Collection var0, Object var1)
4. join(Collection c, String joinWith)
5. join(Collection collection, String joinString)
6. join(Collection elements, String separator)
7. join(Collection list, String separator)
8. join(Collection objects, String delim)
9. join(Collection strings, String separator)