| /* |
| * QR Code generator library (Java) |
| * |
| * Copyright (c) Project Nayuki. (MIT License) |
| * https://www.nayuki.io/page/qr-code-generator-library |
| * |
| * 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.qrcodegen; |
| |
| import java.nio.charset.StandardCharsets; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Objects; |
| import java.util.regex.Pattern; |
| |
| |
| /** |
| * Represents a character string to be encoded in a QR Code symbol. Each segment has |
| * a mode, and a sequence of characters that is already encoded as a sequence of bits. |
| * Instances of this class are immutable. |
| * <p>This segment class imposes no length restrictions, but QR Codes have restrictions. |
| * Even in the most favorable conditions, a QR Code can only hold 7089 characters of data. |
| * Any segment longer than this is meaningless for the purpose of generating QR Codes.</p> |
| */ |
| public final class QrSegment { |
| |
| /*---- Static factory functions ----*/ |
| |
| /** |
| * Returns a segment representing the specified binary data encoded in byte mode. |
| * @param data the binary data |
| * @return a segment containing the data |
| * @throws NullPointerException if the array is {@code null} |
| */ |
| public static QrSegment makeBytes(byte[] data) { |
| Objects.requireNonNull(data); |
| BitBuffer bb = new BitBuffer(); |
| for (byte b : data) |
| bb.appendBits(b & 0xFF, 8); |
| return new QrSegment(Mode.BYTE, data.length, bb); |
| } |
| |
| |
| /** |
| * Returns a segment representing the specified string of decimal digits encoded in numeric mode. |
| * @param digits a string consisting of digits from 0 to 9 |
| * @return a segment containing the data |
| * @throws NullPointerException if the string is {@code null} |
| * @throws IllegalArgumentException if the string contains non-digit characters |
| */ |
| public static QrSegment makeNumeric(String digits) { |
| Objects.requireNonNull(digits); |
| if (!NUMERIC_REGEX.matcher(digits).matches()) |
| throw new IllegalArgumentException("String contains non-numeric characters"); |
| |
| BitBuffer bb = new BitBuffer(); |
| int i; |
| for (i = 0; i + 3 <= digits.length(); i += 3) // Process groups of 3 |
| bb.appendBits(Integer.parseInt(digits.substring(i, i + 3)), 10); |
| int rem = digits.length() - i; |
| if (rem > 0) // 1 or 2 digits remaining |
| bb.appendBits(Integer.parseInt(digits.substring(i)), rem * 3 + 1); |
| return new QrSegment(Mode.NUMERIC, digits.length(), bb); |
| } |
| |
| |
| /** |
| * Returns a segment representing the specified text string encoded in alphanumeric mode. |
| * The characters allowed are: 0 to 9, A to Z (uppercase only), space, |
| * dollar, percent, asterisk, plus, hyphen, period, slash, colon. |
| * @param text a string of text, with only certain characters allowed |
| * @return a segment containing the data |
| * @throws NullPointerException if the string is {@code null} |
| * @throws IllegalArgumentException if the string contains non-encodable characters |
| */ |
| public static QrSegment makeAlphanumeric(String text) { |
| Objects.requireNonNull(text); |
| if (!ALPHANUMERIC_REGEX.matcher(text).matches()) |
| throw new IllegalArgumentException("String contains unencodable characters in alphanumeric mode"); |
| |
| BitBuffer bb = new BitBuffer(); |
| int i; |
| for (i = 0; i + 2 <= text.length(); i += 2) { // Process groups of 2 |
| int temp = ALPHANUMERIC_CHARSET.indexOf(text.charAt(i)) * 45; |
| temp += ALPHANUMERIC_CHARSET.indexOf(text.charAt(i + 1)); |
| bb.appendBits(temp, 11); |
| } |
| if (i < text.length()) // 1 character remaining |
| bb.appendBits(ALPHANUMERIC_CHARSET.indexOf(text.charAt(i)), 6); |
| return new QrSegment(Mode.ALPHANUMERIC, text.length(), bb); |
| } |
| |
| |
| /** |
| * Returns a new mutable list of zero or more segments to represent the specified Unicode text string. |
| * The result may use various segment modes and switch modes to optimize the length of the bit stream. |
| * @param text the text to be encoded, which can be any Unicode string |
| * @return a list of segments containing the text |
| * @throws NullPointerException if the text is {@code null} |
| */ |
| public static List<QrSegment> makeSegments(String text) { |
| Objects.requireNonNull(text); |
| |
| // Select the most efficient segment encoding automatically |
| List<QrSegment> result = new ArrayList<>(); |
| if (text.equals("")); // Leave result empty |
| else if (NUMERIC_REGEX.matcher(text).matches()) |
| result.add(makeNumeric(text)); |
| else if (ALPHANUMERIC_REGEX.matcher(text).matches()) |
| result.add(makeAlphanumeric(text)); |
| else |
| result.add(makeBytes(text.getBytes(StandardCharsets.UTF_8))); |
| return result; |
| } |
| |
| |
| /** |
| * Returns a segment representing an Extended Channel Interpretation |
| * (ECI) designator with the specified assignment value. |
| * @param assignVal the ECI assignment number (see the AIM ECI specification) |
| * @return a segment containing the data |
| * @throws IllegalArgumentException if the value is outside the range [0, 10<sup>6</sup>) |
| */ |
| 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); |
| } |
| |
| |
| |
| /*---- Instance fields ----*/ |
| |
| /** The mode indicator for this segment. Never {@code null}. */ |
| public final Mode mode; |
| |
| /** The length of this segment's unencoded data, measured in characters. Always zero or positive. */ |
| public final int numChars; |
| |
| /** The data bits of this segment. Accessed through {@link getBits()}. Not {@code null}. */ |
| final BitBuffer data; |
| |
| |
| /*---- Constructor ----*/ |
| |
| /** |
| * Creates a new QR Code data segment with the specified parameters and data. |
| * @param md the mode, which is not {@code null} |
| * @param numCh the data length in characters, which is non-negative |
| * @param data the data bits of this segment, which is not {@code null} |
| * @throws NullPointerException if the mode or bit buffer is {@code null} |
| * @throws IllegalArgumentException if the character count is negative |
| */ |
| public QrSegment(Mode md, int numCh, BitBuffer data) { |
| Objects.requireNonNull(md); |
| Objects.requireNonNull(data); |
| if (numCh < 0) |
| throw new IllegalArgumentException("Invalid value"); |
| mode = md; |
| numChars = numCh; |
| this.data = data.clone(); // Make defensive copy |
| } |
| |
| |
| /*---- Methods ----*/ |
| |
| /** |
| * Returns the data bits of this segment. |
| * @return the data bits of this segment (not {@code null}) |
| */ |
| public BitBuffer getBits() { |
| return data.clone(); // Make defensive copy |
| } |
| |
| |
| // Package-private helper function. |
| static int getTotalBits(List<QrSegment> segs, int version) { |
| Objects.requireNonNull(segs); |
| if (version < 1 || version > 40) |
| throw new IllegalArgumentException("Version number out of range"); |
| |
| long result = 0; |
| for (QrSegment seg : segs) { |
| Objects.requireNonNull(seg); |
| int ccbits = seg.mode.numCharCountBits(version); |
| // Fail if segment length value doesn't fit in the length field's bit-width |
| if (seg.numChars >= (1 << ccbits)) |
| return -1; |
| result += 4L + ccbits + seg.data.bitLength(); |
| if (result > Integer.MAX_VALUE) |
| return -1; |
| } |
| return (int)result; |
| } |
| |
| |
| /*---- Constants ----*/ |
| |
| /** Can test whether a string is encodable in numeric mode (such as by using {@link #makeNumeric(String)}). */ |
| public static final Pattern NUMERIC_REGEX = Pattern.compile("[0-9]*"); |
| |
| /** Can test whether a string is encodable in alphanumeric mode (such as by using {@link #makeAlphanumeric(String)}). */ |
| public static final Pattern ALPHANUMERIC_REGEX = Pattern.compile("[A-Z0-9 $%*+./:-]*"); |
| |
| /** The set of all legal characters in alphanumeric mode, where each character value maps to the index in the string. */ |
| private static final String ALPHANUMERIC_CHARSET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:"; |
| |
| |
| |
| /*---- Public helper enumeration ----*/ |
| |
| /** |
| * The mode field of a segment. Immutable. Provides methods to retrieve closely related values. |
| */ |
| 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 --*/ |
| |
| /** An unsigned 4-bit integer value (range 0 to 15) representing the mode indicator bits for this mode object. */ |
| final int modeBits; |
| |
| private final int[] numBitsCharCount; |
| |
| |
| /*-- Constructor --*/ |
| |
| private Mode(int mode, int... ccbits) { |
| this.modeBits = mode; |
| numBitsCharCount = ccbits; |
| } |
| |
| |
| /*-- Method --*/ |
| |
| /** |
| * Returns the bit width of the segment character count field for this mode object at the specified version number. |
| * @param ver the version number, which is between 1 to 40, inclusive |
| * @return the number of bits for the character count, which is between 8 to 16, inclusive |
| * @throws IllegalArgumentException if the version number is out of range |
| */ |
| 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"); |
| } |
| |
| } |
| |
| } |