From d842b7ca57efbc179de6110483206788304f4a8d Mon Sep 17 00:00:00 2001 From: Project Nayuki Date: Thu, 23 Nov 2017 04:02:58 +0000 Subject: [PATCH] Implement QR segment class, exposed bit buffer fields to the package. --- src/io/nayuki/fastqrcodegen/BitBuffer.java | 4 +- src/io/nayuki/fastqrcodegen/QrSegment.java | 227 +++++++++++++++++++++ 2 files changed, 229 insertions(+), 2 deletions(-) create mode 100644 src/io/nayuki/fastqrcodegen/QrSegment.java diff --git a/src/io/nayuki/fastqrcodegen/BitBuffer.java b/src/io/nayuki/fastqrcodegen/BitBuffer.java index ec47819..a73158b 100644 --- a/src/io/nayuki/fastqrcodegen/BitBuffer.java +++ b/src/io/nayuki/fastqrcodegen/BitBuffer.java @@ -30,9 +30,9 @@ final class BitBuffer { /*---- Fields ----*/ - private int[] data; + int[] data; - private int bitLength; + int bitLength; diff --git a/src/io/nayuki/fastqrcodegen/QrSegment.java b/src/io/nayuki/fastqrcodegen/QrSegment.java new file mode 100644 index 0000000..44a9689 --- /dev/null +++ b/src/io/nayuki/fastqrcodegen/QrSegment.java @@ -0,0 +1,227 @@ +/* + * Fast QR Code generator library + * + * Copyright (c) Project Nayuki. (MIT License) + * https://www.nayuki.io/ + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * - The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * - The Software is provided "as is", without warranty of any kind, express or + * implied, including but not limited to the warranties of merchantability, + * fitness for a particular purpose and noninfringement. In no event shall the + * authors or copyright holders be liable for any claim, damages or other + * liability, whether in an action of contract, tort or otherwise, arising from, + * out of or in connection with the Software or the use or other dealings in the + * Software. + */ + +package io.nayuki.fastqrcodegen; + +import java.nio.charset.StandardCharsets; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.List; +import java.util.Objects; + + +public final class QrSegment { + + /*---- Static factory functions ----*/ + + public static QrSegment makeBytes(byte[] data) { + Objects.requireNonNull(data); + int[] bits = new int[(data.length + 3) / 4]; + for (int i = 0; i < data.length; i++) + bits[i >>> 2] |= (data[i] & 0xFF) << (~i << 3); + return new QrSegment(Mode.BYTE, data.length, bits, data.length * 8); + } + + + public static QrSegment makeNumeric(String digits) { + Objects.requireNonNull(digits); + BitBuffer bb = new BitBuffer(); + int accumData = 0; + int accumCount = 0; + for (int i = 0; i < digits.length(); i++) { + char c = digits.charAt(i); + if (c < '0' || c > '9') + throw new IllegalArgumentException("String contains non-numeric characters"); + accumData = accumData * 10 + (c - '0'); + accumCount++; + if (accumCount == 3) { + bb.appendBits(accumData, 10); + accumData = 0; + accumCount = 0; + } + } + if (accumCount > 0) // 1 or 2 digits remaining + bb.appendBits(accumData, accumCount * 3 + 1); + return new QrSegment(Mode.NUMERIC, digits.length(), bb.data, bb.bitLength); + } + + + public static QrSegment makeAlphanumeric(String text) { + Objects.requireNonNull(text); + BitBuffer bb = new BitBuffer(); + int accumData = 0; + int accumCount = 0; + for (int i = 0; i < text.length(); i++) { + char c = text.charAt(i); + if (c >= ALPHANUMERIC_MAP.length || ALPHANUMERIC_MAP[c] == -1) + throw new IllegalArgumentException("String contains unencodable characters in alphanumeric mode"); + accumData = accumData * 10 + ALPHANUMERIC_MAP[c]; + accumCount++; + if (accumCount == 2) { + bb.appendBits(accumData, 11); + accumData = 0; + accumCount = 0; + } + } + if (accumCount > 0) // 1 character remaining + bb.appendBits(accumData, 6); + return new QrSegment(Mode.ALPHANUMERIC, text.length(), bb.data, bb.bitLength); + } + + + public static List makeSegments(String text) { + Objects.requireNonNull(text); + + // Select the most efficient segment encoding automatically + List result = new ArrayList<>(); + if (text.equals("")); // Leave result empty + else if (isNumeric(text)) + result.add(makeNumeric(text)); + else if (isAlphanumeric(text)) + result.add(makeAlphanumeric(text)); + else + result.add(makeBytes(text.getBytes(StandardCharsets.UTF_8))); + return result; + } + + + public static QrSegment makeEci(int assignVal) { + BitBuffer bb = new BitBuffer(); + if (0 <= assignVal && assignVal < (1 << 7)) + bb.appendBits(assignVal, 8); + else if ((1 << 7) <= assignVal && assignVal < (1 << 14)) { + bb.appendBits(2, 2); + bb.appendBits(assignVal, 14); + } else if ((1 << 14) <= assignVal && assignVal < 1000000) { + bb.appendBits(6, 3); + bb.appendBits(assignVal, 21); + } else + throw new IllegalArgumentException("ECI assignment value out of range"); + return new QrSegment(Mode.ECI, 0, bb.data, bb.bitLength); + } + + + public static boolean isNumeric(String text) { + for (int i = 0; i < text.length(); i++) { + char c = text.charAt(i); + if (c < '0' || c > '9') + return false; + } + return true; + } + + + public static boolean isAlphanumeric(String text) { + for (int i = 0; i < text.length(); i++) { + char c = text.charAt(i); + if (c >= ALPHANUMERIC_MAP.length || ALPHANUMERIC_MAP[c] == -1) + return false; + } + return true; + } + + + + /*---- Instance fields ----*/ + + public final Mode mode; + + public final int numChars; + + final int[] data; + + final int bitLength; + + + /*---- Constructor ----*/ + + public QrSegment(Mode md, int numCh, int[] data, int bitLen) { + Objects.requireNonNull(md); + Objects.requireNonNull(data); + if (numCh < 0 || bitLen < 0 || bitLen > data.length * 32) + throw new IllegalArgumentException("Invalid value"); + mode = md; + numChars = numCh; + this.data = data; + bitLength = bitLen; + } + + + + /*---- Constants ----*/ + + private static final int[] ALPHANUMERIC_MAP; + + static { + final String ALPHANUMERIC_CHARSET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:"; + int maxCh = -1; + for (int i = 0; i < ALPHANUMERIC_CHARSET.length(); i++) + maxCh = Math.max(ALPHANUMERIC_CHARSET.charAt(i), maxCh); + ALPHANUMERIC_MAP = new int[maxCh + 1]; + Arrays.fill(ALPHANUMERIC_MAP, -1); + for (int i = 0; i < ALPHANUMERIC_CHARSET.length(); i++) + ALPHANUMERIC_MAP[ALPHANUMERIC_CHARSET.charAt(i)] = i; + } + + + + /*---- Public helper enumeration ----*/ + + public enum Mode { + + /*-- Constants --*/ + + NUMERIC (0x1, 10, 12, 14), + ALPHANUMERIC(0x2, 9, 11, 13), + BYTE (0x4, 8, 16, 16), + KANJI (0x8, 8, 10, 12), + ECI (0x7, 0, 0, 0); + + + /*-- Fields --*/ + + final int modeBits; + + private final int[] numBitsCharCount; + + + /*-- Constructor --*/ + + private Mode(int mode, int... ccbits) { + this.modeBits = mode; + numBitsCharCount = ccbits; + } + + + /*-- Method --*/ + + int numCharCountBits(int ver) { + if ( 1 <= ver && ver <= 9) return numBitsCharCount[0]; + else if (10 <= ver && ver <= 26) return numBitsCharCount[1]; + else if (27 <= ver && ver <= 40) return numBitsCharCount[2]; + else throw new IllegalArgumentException("Version number out of range"); + } + + } + +}