StringUtil.java

/*
 * This file is part of the OdinMS Maple Story Server Copyright (C) 2008 ~ 2010
 * Patrick Huy <patrick.huy@frz.cc> Matthias Butz <matze@odinms.de> Jan
 * Christian Meyer <vimes@odinms.de>
 * 
 * This program is free software: you can redistribute it and/or modify it under
 * the terms of the GNU Affero General Public License version 3 as published by
 * the Free Software Foundation. You may not use, modify or distribute this
 * program under any other version of the GNU Affero General Public License.
 * 
 * This program 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 Affero General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package javastory.tools;

/**
 * Provides a suite of utilities for manipulating strings.
 * 
 * @author Frz
 * @since Revision 336
 * @version 1.0
 * 
 */
public class StringUtil {

	/**
	 * Gets a string padded from the left to <code>length</code> by
	 * <code>padchar</code>.
	 * 
	 * @param in
	 *            The input string to be padded.
	 * @param padchar
	 *            The character to pad with.
	 * @param length
	 *            The length to pad to.
	 * @return The padded string.
	 */
	public static final String getLeftPaddedStr(final String in, final char padchar, final int length) {
		final StringBuilder builder = new StringBuilder(length);
		for (int x = in.length(); x < length; x++) {
			builder.append(padchar);
		}
		builder.append(in);
		return builder.toString();
	}

	/**
	 * Gets a string padded from the right to <code>length</code> by
	 * <code>padchar</code>.
	 * 
	 * @param in
	 *            The input string to be padded.
	 * @param padchar
	 *            The character to pad with.
	 * @param length
	 *            The length to pad to.
	 * @return The padded string.
	 */
	public static final String getRightPaddedStr(final String in, final char padchar, final int length) {
		final StringBuilder builder = new StringBuilder(in);
		for (int x = in.length(); x < length; x++) {
			builder.append(padchar);
		}
		return builder.toString();
	}

	/**
	 * Joins an array of strings starting from string <code>start</code> with a
	 * space.
	 * 
	 * @param arr
	 *            The array of strings to join.
	 * @param start
	 *            Starting from which string.
	 * @return The joined strings.
	 */
	public static final String joinStringFrom(final String arr[], final int start) {
		return joinStringFrom(arr, start, " ");
	}

	/**
	 * Joins an array of strings starting from string <code>start</code> with
	 * <code>sep</code> as a seperator.
	 * 
	 * @param arr
	 *            The array of strings to join.
	 * @param start
	 *            Starting from which string.
	 * @return The joined strings.
	 */
	public static final String joinStringFrom(final String arr[], final int start, final String sep) {
		final StringBuilder builder = new StringBuilder();
		for (int i = start; i < arr.length; i++) {
			builder.append(arr[i]);
			if (i != arr.length - 1) {
				builder.append(sep);
			}
		}
		return builder.toString();
	}

	/**
	 * Makes an enum name human readable (fixes spaces, capitalization, etc)
	 * 
	 * @param enumName
	 *            The name of the enum to neaten up.
	 * @return The human-readable enum name.
	 */
	public static final String makeEnumHumanReadable(final String enumName) {
		final StringBuilder builder = new StringBuilder(enumName.length() + 1);
		for (final String word : enumName.split("_")) {
			if (word.length() <= 2) {
				builder.append(word); // assume that it's an abbrevation
			} else {
				builder.append(word.charAt(0));
				builder.append(word.substring(1).toLowerCase());
			}
			builder.append(' ');
		}
		return builder.substring(0, enumName.length());
	}

	/**
	 * Counts the number of <code>chr</code>'s in <code>str</code>.
	 * 
	 * @param str
	 *            The string to check for instances of <code>chr</code>.
	 * @param chr
	 *            The character to check for.
	 * @return The number of times <code>chr</code> occurs in <code>str</code>.
	 */
	public static final int countCharacters(final String str, final char chr) {
		int ret = 0;
		for (int i = 0; i < str.length(); i++) {
			if (str.charAt(i) == chr) {
				ret++;
			}
		}
		return ret;
	}
}