Java Collection Join join(String sep, Collection col)

Description

Returns string that contains of all elements of passed collection joined together

License

Open Source License

Parameter

Parameter	Description
sep	separator (inserted between values)
col	collection of values to concatenate

Return

concatenated string

Declaration

public static String join(String sep, Collection<?> col) 

Method Source Code

//package com.java2s;
/**//from w  w  w  . jav a  2  s. co m
 * Copyright 2012-2015 Rafal Lewczuk <rafal.lewczuk@jitlogic.com>
 *
 * ZORKA is free software. You can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 *
 * ZORKA is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * ZORKA. If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.*;

public class Main {
    /**
     * Returns string that contains of all elements of passed collection joined together
     *
     * @param sep separator (inserted between values)
     * @param col collection of values to concatenate
     * @return concatenated string
     */
    public static String join(String sep, Collection<?> col) {
        StringBuilder sb = new StringBuilder();

        for (Object val : col) {
            if (sb.length() > 0)
                sb.append(sep);
            sb.append(castString(val));
        }

        return sb.toString();
    }

    /**
     * Returns string that contains of all elements of passed (vararg) array joined together
     *
     * @param sep  separator (inserted between values)
     * @param vals array of values
     * @return concatenated string
     */
    public static String join(String sep, Object... vals) {
        StringBuilder sb = new StringBuilder();

        for (Object val : vals) {
            if (sb.length() > 0)
                sb.append(sep);
            sb.append(castString(val));
        }

        return sb.toString();
    }

    public static String castString(Object val) {
        try {
            return val != null ? val.toString() : "null";
        } catch (Exception e) {
            return "<ERR: " + e.getMessage() + ">";
        }
    }
}

Related

1. join(String glue, Collection strings)
2. join(String glue, Collection items)
3. join(String join_string, Collection c)
4. join(String joiner, Collection strings)
5. join(String sep, Collection objects)
6. join(String sep, Collection col)
7. join(String sep, Collection parts)
8. join(String sep, Collection values)
9. join(String sep, Collection values)