Java Array Join join(int[] array, String separator)

Description

Joins the given ints using the given separator into a single string.

License

Apache License

Return

the joined string or an empty string if the int array is null

Declaration

public static String join(int[] array, String separator) 

Method Source Code

//package com.java2s;
/*//from   w ww  .jav  a2  s  .  c  o  m
 * Copyright (C) 2014 Markus Junginger, greenrobot (http://greenrobot.de)
 *
 * 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.Iterator;

public class Main {
    /**
     * Joins the given iterable objects using the given separator into a single string.
     *
     * @return the joined string or an empty string if iterable is null
     */
    public static String join(Iterable<?> iterable, String separator) {
        if (iterable != null) {
            StringBuilder buf = new StringBuilder();
            Iterator<?> it = iterable.iterator();
            char singleChar = separator.length() == 1 ? separator.charAt(0) : 0;
            while (it.hasNext()) {
                buf.append(it.next());
                if (it.hasNext()) {
                    if (singleChar != 0) {
                        // More efficient
                        buf.append(singleChar);
                    } else {
                        buf.append(separator);
                    }
                }
            }
            return buf.toString();
        } else {
            return "";
        }
    }

    /**
     * Joins the given ints using the given separator into a single string.
     *
     * @return the joined string or an empty string if the int array is null
     */
    public static String join(int[] array, String separator) {
        if (array != null) {
            StringBuilder buf = new StringBuilder(Math.max(16, (separator.length() + 1) * array.length));
            char singleChar = separator.length() == 1 ? separator.charAt(0) : 0;
            for (int i = 0; i < array.length; i++) {
                if (i != 0) {
                    if (singleChar != 0) {
                        // More efficient
                        buf.append(singleChar);
                    } else {
                        buf.append(separator);
                    }
                }
                buf.append(array[i]);
            }
            return buf.toString();
        } else {
            return "";
        }
    }

    /**
     * Joins the given Strings using the given separator into a single string.
     *
     * @return the joined string or an empty string if the String array is null
     */
    public static String join(String[] array, String separator) {
        if (array != null) {
            StringBuilder buf = new StringBuilder(Math.max(16, (separator.length() + 1) * array.length));
            char singleChar = separator.length() == 1 ? separator.charAt(0) : 0;
            for (int i = 0; i < array.length; i++) {
                if (i != 0) {
                    if (singleChar != 0) {
                        // More efficient
                        buf.append(singleChar);
                    } else {
                        buf.append(separator);
                    }
                }
                buf.append(array[i]);
            }
            return buf.toString();
        } else {
            return "";
        }
    }
}

Related

1. join(final String[] strings)
2. join(final String[] strings, final String joinString)
3. join(final String[] values, final String delimiter)
4. join(final T[] array, final char c)
5. join(final T[] collection)
6. join(int[] follows)
7. join(long[] a, long[] b)
8. join(long[] array, String delim)
9. join(Object[] arguments)