stevedlawrence commented on a change in pull request #16: Implemented packed binary formats URL: https://github.com/apache/incubator-daffodil/pull/16#discussion_r161796290
########## File path: daffodil-lib/src/main/scala/edu/illinois/ncsa/daffodil/util/DecimalUtils.scala ########## @@ -0,0 +1,342 @@ +/* + * 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 edu.illinois.ncsa.daffodil.util + +import edu.illinois.ncsa.daffodil.schema.annotation.props.gen.BinaryNumberCheckPolicy + +import java.math.{ BigInteger => JBigInteger, BigDecimal => JBigDecimal } + +object DecimalUtils { + + def signCodesToHex(signCodes: String, policy: BinaryNumberCheckPolicy): Map[String, List[Int]] = { + // remove all spaces from the string + val str: String = signCodes.replaceAll("\\s", "") + val chars: Array[Char] = str.toCharArray() + + val valid_positives: List[Int] = List( + Integer.parseInt(String.valueOf('A'), 16), + Integer.parseInt(String.valueOf('C'), 16), + Integer.parseInt(String.valueOf('E'), 16), + Integer.parseInt(String.valueOf('F'), 16)) + val valid_negatives: List[Int] = List( + Integer.parseInt(String.valueOf('B'), 16), + Integer.parseInt(String.valueOf('D'), 16)) + val valid_unsigneds: List[Int] = List( + Integer.parseInt(String.valueOf('F'), 16)) + val valid_zero_signs: List[Int] = List( + Integer.parseInt(String.valueOf('A'), 16), + Integer.parseInt(String.valueOf('C'), 16), + Integer.parseInt(String.valueOf('E'), 16), + Integer.parseInt(String.valueOf('F'), 16), + Integer.parseInt(String.valueOf('0'), 16)) + + val positives: List[Int] = List(Integer.parseInt(String.valueOf(chars(0)), 16)) + val negatives: List[Int] = List(Integer.parseInt(String.valueOf(chars(1)), 16)) + val unsigneds: List[Int] = List(Integer.parseInt(String.valueOf(chars(2)), 16)) + val zero_signs: List[Int] = List(Integer.parseInt(String.valueOf(chars(3)), 16)) + + val hexCodes = policy match { + case BinaryNumberCheckPolicy.Strict => Map("positive" -> positives, "negative" -> negatives, "unsigned" -> unsigneds, "zero_sign" -> zero_signs) + case BinaryNumberCheckPolicy.Lax => Map("positive" -> valid_positives, "negative" -> valid_negatives, "unsigned" -> valid_unsigneds, "zero_sign" -> valid_zero_signs) + } + + hexCodes + } + + def packedToBigInteger(num: Array[Byte], signCodes: String, policy: BinaryNumberCheckPolicy): JBigInteger = { + val hexCodes: Map[String, List[Int]] = signCodesToHex(signCodes, policy) + val numDigits: Int = num.size * 2 // 2 digits stored per byte + val outputData: Array[Char] = new Array[Char](numDigits-1) + var outputPos: Int = 0 + var offset: Int = 0 + var nibble: Int = 0 + var negative: Boolean = false + + // Parse and validate the last (sign) bit + nibble = (num(offset + num.size - 1) & 0x0F) + if (hexCodes("negative").contains(nibble)) { + negative = true + } else if (!hexCodes("positive").contains(nibble)) { + throw new NumberFormatException("Invalid low nibble") + } + + while (outputPos < outputData.size - 1) { + // Parse high nibble + nibble = (num(offset) & 0xFF) >>> 4 + if (nibble > 0x09) { + throw new NumberFormatException("Invalid high nibble") + } + + outputData(outputPos) = (nibble | 0x0030).toChar + outputPos = outputPos + 1 + + // Parse low nibble + nibble = (num(offset) & 0x0F) + offset = offset + 1 + if (nibble > 0x09) { + throw new NumberFormatException("Invalid low nibble") + } + + outputData(outputPos) = (nibble | 0x0030).toChar + outputPos = outputPos + 1 + } + + // Parse last digit + nibble = (num(offset) & 0xFF) >>> 4 + if (nibble > 0x09) { + throw new NumberFormatException("Invalid high nibble") + } + + outputData(outputPos) = (nibble | 0x0030).toChar + + if (negative) + new JBigInteger(new String(outputData)).negate() + else + new JBigInteger(new String(outputData)) + Review comment: Minor, but I'd prefer to see this as ``` val jbi = JBigInteger(new String(outputData)) if (negative) jbi.negate() else jbi ``` Removes code duplication. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
