StringUtil.java |
package org.appfuse.util; import java.io.IOException; import java.security.MessageDigest; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * String Utility Class This is used to encode passwords programmatically * * <p> * <a href="StringUtil.java.html"><i>View Source</i></a> * </p> * * @author <a href="mailto:matt@raibledesigns.com">Matt Raible</a> * @version $Revision: 1.1 $ $Date: 2004/03/31 13:04:17 $ */ public class StringUtil extends BaseUtil { //~ Static fields/initializers ============================================= /** The <code>Log</code> instance for this class. */ private static Log log = LogFactory.getLog(StringUtil.class); //~ Methods ================================================================ /** * Encode a string using algorithm specified in web.xml and return the * resulting encrypted password. If exception, the plain credentials * string is returned * * @param password Password or other credentials to use in authenticating * this username * @param algorithm Algorithm used to do the digest * * @return encypted password based on the algorithm. */ public static String encodePassword(String password, String algorithm) { byte[] unencodedPassword = password.getBytes(); MessageDigest md = null; try { // first create an instance, given the provider md = MessageDigest.getInstance(algorithm); } catch (Exception e) { log.error("Exception: " + e); return password; } md.reset(); // call the update method one or more times // (useful when you don't know the size of your data, eg. stream) md.update(unencodedPassword); // now calculate the hash byte[] encodedPassword = md.digest(); StringBuffer buf = new StringBuffer(); for (int i = 0; i < encodedPassword.length; i++) { if (((int) encodedPassword[i] & 0xff) < 0x10) { buf.append("0"); } buf.append(Long.toString((int) encodedPassword[i] & 0xff, 16)); } return buf.toString(); } /** * Encode a string using Base64 encoding. Used when storing passwords * as cookies. * * This is weak encoding in that anyone can use the decodeString * routine to reverse the encoding. * * @param str * @return String * @throws IOException */ public static String encodeString(String str) throws IOException { sun.misc.BASE64Encoder encoder = new sun.misc.BASE64Encoder(); String encodedStr = new String(encoder.encodeBuffer(str.getBytes())); return (encodedStr.trim()); } /** * Decode a string using Base64 encoding. * * @param str * @return String * @throws IOException */ public static String decodeString(String str) throws IOException { sun.misc.BASE64Decoder dec = new sun.misc.BASE64Decoder(); String value = new String(dec.decodeBuffer(str)); return (value); } }
StringUtil.java |