sascha@301: /*
sascha@301:  * Copyright (c) 2010 by Intevation GmbH
sascha@301:  *
sascha@301:  * This program is free software under the LGPL (>=v2.1)
sascha@301:  * Read the file LGPL.txt coming with the software for details
sascha@301:  * or visit http://www.gnu.org/licenses/ if it does not exist.
sascha@301:  */
sascha@301: 
teichmann@475: package org.dive4elements.artifacts.common.utils;
sascha@301: 
sascha@301: import java.io.UnsupportedEncodingException;
sascha@301: 
sascha@301: import java.util.UUID;
sascha@301: 
sascha@301: import org.apache.commons.codec.DecoderException;
sascha@301: 
sascha@301: import org.apache.commons.codec.binary.Hex;
sascha@301: 
sascha@301: import org.apache.log4j.Logger;
sascha@301: 
sascha@301: /**
sascha@301:  * Commonly used string functions.
sascha@301:  *
sascha@301:  * @author <a href="mailto:sascha.teichmann@intevation.de">Sascha L. Teichmann</a>
sascha@301:  */
sascha@301: public final class StringUtils
sascha@301: {
sascha@301:     private static Logger logger = Logger.getLogger(StringUtils.class);
sascha@301: 
sascha@301:     /**
sascha@301:      * Generated a random UUIDv4 in form of a string.
sascha@301:      * @return the UUID
sascha@301:      */
sascha@301:     public static final String newUUID() {
sascha@301:         return UUID.randomUUID().toString();
sascha@301:     }
sascha@301: 
sascha@301:     /**
sascha@301:      * Checks if a given string is a valid UUID.
sascha@301:      * @param uuid The string to test.
sascha@301:      * @return true if the string is a valid UUID else false.
sascha@301:      */
sascha@301:     public static final boolean checkUUID(String uuid) {
sascha@301:         try {
sascha@301:             UUID.fromString(uuid);
sascha@301:         }
sascha@301:         catch (IllegalArgumentException iae) {
sascha@301:             logger.warn(iae.getLocalizedMessage());
sascha@301:             return false;
sascha@301:         }
sascha@301:         return true;
sascha@301:     }
sascha@301: 
sascha@301:     /**
sascha@301:      * Returns the UTF-8 byte array representation of a given string.
sascha@301:      * @param s The string to be transformed.
sascha@301:      * @return The byte array representation.
sascha@301:      */
sascha@301:     public static final byte [] getUTF8Bytes(String s) {
sascha@301:         try {
sascha@301:             return s.getBytes("UTF-8");
sascha@301:         }
sascha@301:         catch (UnsupportedEncodingException usee) {
sascha@301:             logger.error(usee.getLocalizedMessage(), usee);
sascha@301:             return s.getBytes();
sascha@301:         }
sascha@301:     }
sascha@301: 
sascha@301:     /**
sascha@301:      * Tries to convert a Base64 encoded string into the
sascha@301:      * corresponing byte array.
sascha@301:      * @param s The Base64 encoded string
sascha@301:      * @return The byte array representation or null if
sascha@301:      * an decoding error occurs.
sascha@301:      */
sascha@301:     public static final byte [] decodeHex(String s) {
sascha@301:         try {
sascha@301:             return Hex.decodeHex(s.toCharArray());
sascha@301:         }
sascha@301:         catch (DecoderException de) {
sascha@301:             return null;
sascha@301:         }
sascha@301:     }
sascha@301: 
sascha@301:     public static final String repeat(String s, int count, String sep) {
sascha@301:         if (count <= 0) {
sascha@301:             return "";
sascha@301:         }
sascha@301:         StringBuilder sb = new StringBuilder(s);
sascha@301:         for (--count; count > 0; --count) {
sascha@301:             sb.append(sep).append(s);
sascha@301:         }
sascha@301:         return sb.toString();
sascha@301:     }
sascha@301: 
sascha@301:     public static final String repeat(char c, int count, char sep) {
sascha@301:         if (count <= 0) {
sascha@301:             return "";
sascha@301:         }
sascha@301:         StringBuilder sb = new StringBuilder(2*count-1).append(c);
sascha@301:         for (--count; count > 0; --count) {
sascha@301:             sb.append(sep).append(c);
sascha@301:         }
sascha@301:         return sb.toString();
sascha@301:     }
sascha@342: 
sascha@342:     public static final String [] toUpperCase(String [] s) {
sascha@342:         if (s == null) {
sascha@342:             return null;
sascha@342:         }
sascha@342:         String [] d = new String[s.length];
sascha@342:         for (int i = 0; i < s.length; ++i) {
sascha@342:             if (s[i] != null) {
sascha@342:                 d[i] = s[i].toUpperCase();
sascha@342:             }
sascha@342:         }
sascha@342:         return d;
sascha@394:     }
sascha@376: 
sascha@376:     public static String join(String sep, String [] strings) {
sascha@376:         StringBuilder sb = new StringBuilder();
sascha@376:         for (int i = 0; i < strings.length; ++i) {
sascha@376:             if (i > 0) sb.append(sep);
sascha@376:             sb.append(strings[i]);
sascha@376:         }
sascha@376:         return sb.toString();
sascha@376:     }
sascha@397: 
sascha@401:     public static final String [] join(String [] a, String [] b) {
sascha@401:         if (a == null && b == null) return null;
sascha@401:         if (a == null) return b;
sascha@401:         if (b == null) return a;
sascha@401:         String [] dst = new String[a.length + b.length];
sascha@401:         System.arraycopy(a, 0, dst, 0, a.length);
sascha@401:         System.arraycopy(b, 0, dst, a.length, b.length);
sascha@401:         return dst;
sascha@401:     }
sascha@401: 
teichmann@498:     public static final int indexOf(String needle, String [] haystack) {
teichmann@498:         for (int i = 0; i < haystack.length; ++i) {
teichmann@498:             if (needle.equals(haystack[i])) {
teichmann@498:                 return i;
sascha@397:             }
sascha@397:         }
teichmann@498:         return -1;
teichmann@498:     }
teichmann@498: 
teichmann@498:     public static final boolean contains(String needle, String [] haystack) {
teichmann@498:         return indexOf(needle, haystack) != -1;
sascha@397:     }
sascha@301: }
sascha@301: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :