jadams-tresys commented on a change in pull request #16: Implemented packed binary formats URL: https://github.com/apache/incubator-daffodil/pull/16#discussion_r162077081
########## 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)) + + } + + def packedToBigDecimal(num: Array[Byte], scale: Int, signCodes: String, policy: BinaryNumberCheckPolicy): JBigDecimal = { + return new JBigDecimal(packedToBigInteger(num, signCodes, policy), scale) + } + + def packedFromBigInteger(num: String, nBits: Int, signCodes:String, policy: BinaryNumberCheckPolicy): Array[Byte] = { + val negative: Boolean = (num.charAt(0) == '-') + // Discard any sign symbols or decimal points from the string (decimal point will be maintained in binaryVirtualDecimalPoint) Review comment: I may not have worded things correctly. I think we are both trying to make the same point, that when both parsing and unparsing we are essentially only dealing with integer values in these byte arrays. In the case of parsing, we shift the decimal point around based on whats in BVDP. When unparsing BVDP isn't used, but I just wanted to convey the fact that even though I am stripping the decimal point from the input string for the FromBigInteger functions, the decimal point information isn't being lost as it is still in BVDP in the schema. ---------------------------------------------------------------- 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
