001 /****************************************************************
002 * Licensed to the Apache Software Foundation (ASF) under one *
003 * or more contributor license agreements. See the NOTICE file *
004 * distributed with this work for additional information *
005 * regarding copyright ownership. The ASF licenses this file *
006 * to you under the Apache License, Version 2.0 (the *
007 * "License"); you may not use this file except in compliance *
008 * with the License. You may obtain a copy of the License at *
009 * *
010 * http://www.apache.org/licenses/LICENSE-2.0 *
011 * *
012 * Unless required by applicable law or agreed to in writing, *
013 * software distributed under the License is distributed on an *
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
015 * KIND, either express or implied. See the License for the *
016 * specific language governing permissions and limitations *
017 * under the License. *
018 ****************************************************************/
019
020 package org.apache.james.mime4j.stream;
021
022 import java.util.BitSet;
023
024 import org.apache.james.mime4j.MimeException;
025 import org.apache.james.mime4j.io.MaxHeaderLengthLimitException;
026 import org.apache.james.mime4j.util.ByteArrayBuffer;
027
028 /**
029 * Default implementation of {@link FieldBuilder}.
030 *
031 */
032 public class DefaultFieldBuilder implements FieldBuilder {
033
034 private static final BitSet FIELD_CHARS = new BitSet();
035
036 static {
037 for (int i = 0x21; i <= 0x39; i++) {
038 FIELD_CHARS.set(i);
039 }
040 for (int i = 0x3b; i <= 0x7e; i++) {
041 FIELD_CHARS.set(i);
042 }
043 }
044
045 private final ByteArrayBuffer buf;
046 private final int maxlen;
047
048 public DefaultFieldBuilder(int maxlen) {
049 this.buf = new ByteArrayBuffer(1024);
050 this.maxlen = maxlen;
051 }
052
053 public void reset() {
054 this.buf.clear();
055 }
056
057 public void append(final ByteArrayBuffer line) throws MaxHeaderLengthLimitException {
058 if (line == null) {
059 return;
060 }
061 int len = line.length();
062 if (this.maxlen > 0 && this.buf.length() + len >= this.maxlen) {
063 throw new MaxHeaderLengthLimitException("Maximum header length limit exceeded");
064 }
065 this.buf.append(line.buffer(), 0, line.length());
066 }
067
068 public RawField build() throws MimeException {
069 int len = this.buf.length();
070 if (len > 0) {
071 if (this.buf.byteAt(len - 1) == '\n') {
072 len --;
073 }
074 if (this.buf.byteAt(len - 1) == '\r') {
075 len --;
076 }
077 }
078 ByteArrayBuffer copy = new ByteArrayBuffer(this.buf.buffer(), len, false);
079 RawField field = RawFieldParser.DEFAULT.parseField(copy);
080 String name = field.getName();
081 for (int i = 0; i < name.length(); i++) {
082 char ch = name.charAt(i);
083 if (!FIELD_CHARS.get(ch)) {
084 throw new MimeException("MIME field name contains illegal characters: "
085 + field.getName());
086 }
087 }
088 return field;
089 }
090
091 public ByteArrayBuffer getRaw() {
092 return this.buf;
093 }
094
095 }