StringUtil.java Source code

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Here is the source code for StringUtil.java

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import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/*
 * JBoss DNA (http://www.jboss.org/dna)
 * See the COPYRIGHT.txt file distributed with this work for information
 * regarding copyright ownership.  Some portions may be licensed
 * to Red Hat, Inc. under one or more contributor license agreements.
 * See the AUTHORS.txt file in the distribution for a full listing of 
 * individual contributors.
 *
 * JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
 * is licensed to you under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * JBoss DNA 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

/**
 * Utilities for string processing and manipulation.
 */
public class StringUtil {

    /**
     * Set the length of the string, padding with the supplied character if the
     * supplied string is shorter than desired, or truncating the string if it is
     * longer than desired. Unlike {@link #justifyLeft(String, int, char)}, this
     * method does not remove leading and trailing whitespace.
     * 
     * @param original
     *          the string for which the length is to be set; may not be null
     * @param length
     *          the desired length; must be positive
     * @param padChar
     *          the character to use for padding, if the supplied string is not
     *          long enough
     * @return the string of the desired length
     * @see #justifyLeft(String, int, char)
     */
    public static String setLength(String original, int length, char padChar) {
        return justifyLeft(original, length, padChar, false);
    }

    protected static String justifyLeft(String str, final int width, char padWithChar, boolean trimWhitespace) {
        // Trim the leading and trailing whitespace ...
        str = str != null ? (trimWhitespace ? str.trim() : str) : "";

        int addChars = width - str.length();
        if (addChars < 0) {
            // truncate
            return str.subSequence(0, width).toString();
        }
        // Write the content ...
        final StringBuilder sb = new StringBuilder();
        sb.append(str);

        // Append the whitespace ...
        while (addChars > 0) {
            sb.append(padWithChar);
            --addChars;
        }

        return sb.toString();
    }

}