/*
* Copyright 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.i18n.server.keygen;
import com.google.gwt.i18n.server.KeyGenerator;
import com.google.gwt.i18n.server.Message;
import com.google.gwt.util.tools.shared.StringUtils;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* Key generator using the MD5 hash of the text and meaning.
*/
public class MD5KeyGenerator implements KeyGenerator {
public String generateKey(Message msg) {
String text = msg.getDefaultMessage();
String meaning = msg.getMeaning();
/*
* This does not use Util.computeStrongName because we would have
* to concatenate the text and meaning into a temporary buffer.
*/
if (text == null) {
// Cannot compute a key if no default text is supplied.
return null;
}
MessageDigest md5;
try {
md5 = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException("Error initializing MD5", e);
}
try {
md5.update(text.getBytes("UTF-8"));
if (meaning != null) {
md5.update(meaning.getBytes("UTF-8"));
}
} catch (UnsupportedEncodingException e) {
throw new RuntimeException("UTF-8 unsupported", e);
}
return StringUtils.toHexString(md5.digest());
}
}