001/* 002 * Copyright 2009-2020 Ping Identity Corporation 003 * All Rights Reserved. 004 */ 005/* 006 * Copyright 2009-2020 Ping Identity Corporation 007 * 008 * Licensed under the Apache License, Version 2.0 (the "License"); 009 * you may not use this file except in compliance with the License. 010 * You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, software 015 * distributed under the License is distributed on an "AS IS" BASIS, 016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 017 * See the License for the specific language governing permissions and 018 * limitations under the License. 019 */ 020/* 021 * Copyright (C) 2009-2020 Ping Identity Corporation 022 * 023 * This program is free software; you can redistribute it and/or modify 024 * it under the terms of the GNU General Public License (GPLv2 only) 025 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only) 026 * as published by the Free Software Foundation. 027 * 028 * This program is distributed in the hope that it will be useful, 029 * but WITHOUT ANY WARRANTY; without even the implied warranty of 030 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 031 * GNU General Public License for more details. 032 * 033 * You should have received a copy of the GNU General Public License 034 * along with this program; if not, see <http://www.gnu.org/licenses>. 035 */ 036package com.unboundid.asn1; 037 038 039 040import com.unboundid.util.Mutable; 041import com.unboundid.util.ThreadSafety; 042import com.unboundid.util.ThreadSafetyLevel; 043 044import static com.unboundid.asn1.ASN1Messages.*; 045 046 047 048/** 049 * This class provides a data structure which is used in the course of reading 050 * an ASN.1 sequence from an ASN.1 stream reader. It provides access to the 051 * BER type and the total number of bytes in the encoded representations of all 052 * of the embedded values, and provides a method to determine when the end of 053 * the sequence has been reached. 054 */ 055@Mutable() 056@ThreadSafety(level=ThreadSafetyLevel.NOT_THREADSAFE) 057public final class ASN1StreamReaderSequence 058{ 059 // The ASN.1 stream reader associated with this object. 060 private final ASN1StreamReader reader; 061 062 // The BER type for this ASN.1 sequence. 063 private final byte type; 064 065 // The number of bytes contained in the encoded representations of all of the 066 // embedded values. 067 private final int length; 068 069 // The value for the total number of bytes read from the associated reader at 070 // which the end of the sequence should be encountered. 071 private final long endBytesRead; 072 073 074 075 /** 076 * Creates a new instance of this class with the provided information. 077 * 078 * @param reader The ASN.1 stream reader with which this object will be 079 * associated. 080 * @param type The BER type for this ASN.1 sequence. 081 * @param length The number of bytes contained in the encoded 082 * representations of all the embedded values. 083 */ 084 ASN1StreamReaderSequence(final ASN1StreamReader reader, final byte type, 085 final int length) 086 { 087 this.reader = reader; 088 this.type = type; 089 this.length = length; 090 091 endBytesRead = reader.getTotalBytesRead() + length; 092 } 093 094 095 096 /** 097 * Retrieves the BER type for this ASN.1 sequence. 098 * 099 * @return The BER type for this ASN.1 sequence. 100 */ 101 public byte getType() 102 { 103 return type; 104 } 105 106 107 108 /** 109 * Retrieves the number of bytes contained in the encoded representations of 110 * all the embedded values. 111 * 112 * @return The number of bytes contained in the encoded representations of 113 * all the embedded values. 114 */ 115 public int getLength() 116 { 117 return length; 118 } 119 120 121 122 /** 123 * Indicates whether there are more elements in this sequence to be read from 124 * the associated ASN.1 stream reader. 125 * 126 * @return {@code true} if there are more elements in this sequence to be 127 * read from the associated ASN.1 stream reader or false if the end 128 * of the sequence has been reached. 129 * 130 * @throws ASN1Exception If the associated ASN.1 stream reader has already 131 * read beyond the end of the sequence. 132 */ 133 public boolean hasMoreElements() 134 throws ASN1Exception 135 { 136 final long currentBytesRead = reader.getTotalBytesRead(); 137 if (currentBytesRead == endBytesRead) 138 { 139 return false; 140 } 141 else if (currentBytesRead < endBytesRead) 142 { 143 return true; 144 } 145 146 throw new ASN1Exception(ERR_STREAM_READER_SEQUENCE_READ_PAST_END.get( 147 length, endBytesRead, currentBytesRead)); 148 } 149}