StringUtil.java Source code

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Here is the source code for StringUtil.java

Source

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 {

    /**
     * Truncate the supplied string to be no more than the specified length. This method returns an empty string if the supplied
     * object is null.
     * 
     * @param obj the object from which the string is to be obtained using {@link Object#toString()}.
     * @param maxLength the maximum length of the string being returned
     * @return the supplied string if no longer than the maximum length, or the supplied string truncated to be no longer than the
     *         maximum length (including the suffix)
     * @throws IllegalArgumentException if the maximum length is negative
     */
    public static String truncate(Object obj, int maxLength) {
        return truncate(obj, maxLength, null);
    }

    /**
     * Truncate the supplied string to be no more than the specified length. This method returns an empty string if the supplied
     * object is null.
     * 
     * @param obj the object from which the string is to be obtained using {@link Object#toString()}.
     * @param maxLength the maximum length of the string being returned
     * @param suffix the suffix that should be added to the content if the string must be truncated, or null if the default suffix
     *        of "..." should be used
     * @return the supplied string if no longer than the maximum length, or the supplied string truncated to be no longer than the
     *         maximum length (including the suffix)
     * @throws IllegalArgumentException if the maximum length is negative
     */
    public static String truncate(Object obj, int maxLength, String suffix) {
        if (obj == null || maxLength == 0) {
            return "";
        }
        String str = obj.toString();
        if (str.length() <= maxLength)
            return str;
        if (suffix == null)
            suffix = "...";
        int maxNumChars = maxLength - suffix.length();
        if (maxNumChars < 0) {
            // Then the max length is actually shorter than the suffix ...
            str = suffix.substring(0, maxLength);
        } else if (str.length() > maxNumChars) {
            str = str.substring(0, maxNumChars) + suffix;
        }
        return str;
    }
}