1 /* 2 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 package org.openjdk.skara.email; 24 25 import java.io.UnsupportedEncodingException; 26 import java.nio.charset.StandardCharsets; 27 import java.util.Base64; 28 import java.util.regex.Pattern; 29 30 public class MimeText { 31 private final static Pattern encodePattern = Pattern.compile("([^\\x00-\\x7f]+)"); 32 private final static Pattern decodePattern = Pattern.compile("=\\?([A-Za-z0-9_.-]+)\\?([bBqQ])\\?(.*?)\\?="); 33 private final static Pattern decodeQuotedPrintablePattern = Pattern.compile("=([0-9A-F]{2})"); 34 35 public static String encode(String raw) { 36 var quoteMatcher = encodePattern.matcher(raw); 37 return quoteMatcher.replaceAll(mo -> "=?utf-8?b?" + Base64.getEncoder().encodeToString(String.valueOf(mo.group(1)).getBytes(StandardCharsets.UTF_8)) + "?="); 38 } 39 40 public static String decode(String encoded) { 41 var quotedMatcher = decodePattern.matcher(encoded); 42 return quotedMatcher.replaceAll(mo -> { 43 try { 44 if (mo.group(2).toUpperCase().equals("B")) { 45 return new String(Base64.getDecoder().decode(mo.group(3)), mo.group(1)); 46 } else { 47 var quotedPrintableMatcher = decodeQuotedPrintablePattern.matcher(mo.group(3)); 48 return quotedPrintableMatcher.replaceAll(qmo -> { 49 var byteValue = new byte[1]; 50 byteValue[0] = (byte)Integer.parseInt(qmo.group(1), 16); 51 try { 52 return new String(byteValue, mo.group(1)); 53 } catch (UnsupportedEncodingException e) { 54 throw new RuntimeException(e); 55 } 56 }); 57 } 58 } catch (UnsupportedEncodingException e) { 59 throw new RuntimeException(e); 60 } 61 }); 62 } 63 }