/*
 *  The Apache Software License, Version 1.1
 *
 *  Copyright (c) 2001 The Apache Software Foundation.  All rights
 *  reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *  notice, this list of conditions and the following disclaimer.
 *
 *  2. Redistributions in binary form must reproduce the above copyright
 *  notice, this list of conditions and the following disclaimer in
 *  the documentation and/or other materials provided with the
 *  distribution.
 *
 *  3. The end-user documentation included with the redistribution, if
 *  any, must include the following acknowlegement:
 *  "This product includes software developed by the
 *  Apache Software Foundation (http://www.apache.org/)."
 *  Alternately, this acknowlegement may appear in the software itself,
 *  if and wherever such third-party acknowlegements normally appear.
 *
 *  4. The names "The Jakarta Project", "Ant", and "Apache Software
 *  Foundation" must not be used to endorse or promote products derived
 *  from this software without prior written permission. For written
 *  permission, please contact apache@apache.org.
 *
 *  5. Products derived from this software may not be called "Apache"
 *  nor may "Apache" appear in their names without prior written
 *  permission of the Apache Group.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 *  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 *  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 *  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 *  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *  ====================================================================
 *
 *  This software consists of voluntary contributions made by many
 *  individuals on behalf of the Apache Software Foundation.  For more
 *  information on the Apache Software Foundation, please see
 *  <http://www.apache.org/>.
 */
package org.apache.ant.common.util;
import java.io.PrintWriter;

import java.io.StringWriter;
import java.util.List;
import java.util.ArrayList;

/**
 *  A set of helper methods related to string manipulation.
 *
 * @author  <a href="mailto:sbailliez@apache.org">Stephane Bailliez</a>
 */
public final class StringUtils {

    /**  the line separator for this OS */
    public static final String LINE_SEP = System.getProperty("line.separator");

    /**
     *  Convenient method to retrieve the full stacktrace from a given
     *  exception.
     *
     * @param  t the exception to get the stacktrace from.
     * @return  the stacktrace from the given exception.
     */
    public static String getStackTrace(Throwable t) {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw, true);
        t.printStackTrace(pw);
        pw.flush();
        pw.close();
        return sw.toString();
    }

    /**
     *  Splits up a string into a list of lines. It is equivalent to <tt>
     *  split(data, '\n')</tt> .
     *
     * @param  data the string to split up into lines.
     * @return  the list of lines available in the string.
     */
    public static List lineSplit(String data) {
        return split(data, '\n');
    }

    /**
     *  Splits up a string where elements are separated by a specific
     *  character and return all elements.
     *
     * @param  data the string to split up.
     * @param  ch the separator character.
     * @return  the list of elements.
     */
    public static List split(String data, int ch) {
        List elems = new ArrayList();
        int pos = -1;
        int i = 0;
        while ((pos = data.indexOf(ch, i)) != -1) {
            String elem = data.substring(i, pos);
            elems.add(elem);
            i = pos + 1;
        }
        elems.add(data.substring(i));
        return elems;
    }

    /**
     *  Replace occurrences into a string.
     *
     * @param  data the string to replace occurrences into
     * @param  from the occurrence to replace.
     * @param  to the occurrence to be used as a replacement.
     * @return  the new string with replaced occurrences.
     */
    public static String replace(String data, String from, String to) {
        StringBuffer buf = new StringBuffer(data.length());
        int pos = -1;
        int i = 0;
        while ((pos = data.indexOf(from, i)) != -1) {
            buf.append(data.substring(i, pos)).append(to);
            i = pos + from.length();
        }
        buf.append(data.substring(i));
        return buf.toString();
    }

}

