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This OSGi bundle wraps ${pkgArtifactId} ${pkgVersion} jar file.
/*
* Copyright 2013 ZXing authors
*
* 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 com.google.zxing.aztec.encoder;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;
import com.google.zxing.common.BitArray;
/**
* State represents all information about a sequence necessary to generate the current output.
* Note that a state is immutable.
*/
final class State {
static final State INITIAL_STATE = new State(Token.EMPTY, HighLevelEncoder.MODE_UPPER, 0, 0);
// The current mode of the encoding (or the mode to which we'll return if
// we're in Binary Shift mode.
private final int mode;
// The list of tokens that we output. If we are in Binary Shift mode, this
// token list does *not* yet included the token for those bytes
private final Token token;
// If non-zero, the number of most recent bytes that should be output
// in Binary Shift mode.
private final int binaryShiftByteCount;
// The total number of bits generated (including Binary Shift).
private final int bitCount;
private final int binaryShiftCost;
private State(Token token, int mode, int binaryBytes, int bitCount) {
this.token = token;
this.mode = mode;
this.binaryShiftByteCount = binaryBytes;
this.bitCount = bitCount;
this.binaryShiftCost = calculateBinaryShiftCost(binaryBytes);
}
int getMode() {
return mode;
}
Token getToken() {
return token;
}
int getBinaryShiftByteCount() {
return binaryShiftByteCount;
}
int getBitCount() {
return bitCount;
}
State appendFLGn(int eci) {
State result = shiftAndAppend(HighLevelEncoder.MODE_PUNCT, 0); // 0: FLG(n)
Token token = result.token;
int bitsAdded = 3;
if (eci < 0) {
token = token.add(0, 3); // 0: FNC1
} else if (eci > 999999) {
throw new IllegalArgumentException("ECI code must be between 0 and 999999");
} else {
byte[] eciDigits = Integer.toString(eci).getBytes(StandardCharsets.ISO_8859_1);
token = token.add(eciDigits.length, 3); // 1-6: number of ECI digits
for (byte eciDigit : eciDigits) {
token = token.add(eciDigit - '0' + 2, 4);
}
bitsAdded += eciDigits.length * 4;
}
return new State(token, mode, 0, bitCount + bitsAdded);
}
// Create a new state representing this state with a latch to a (not
// necessary different) mode, and then a code.
State latchAndAppend(int mode, int value) {
int bitCount = this.bitCount;
Token token = this.token;
if (mode != this.mode) {
int latch = HighLevelEncoder.LATCH_TABLE[this.mode][mode];
token = token.add(latch & 0xFFFF, latch >> 16);
bitCount += latch >> 16;
}
int latchModeBitCount = mode == HighLevelEncoder.MODE_DIGIT ? 4 : 5;
token = token.add(value, latchModeBitCount);
return new State(token, mode, 0, bitCount + latchModeBitCount);
}
// Create a new state representing this state, with a temporary shift
// to a different mode to output a single value.
State shiftAndAppend(int mode, int value) {
Token token = this.token;
int thisModeBitCount = this.mode == HighLevelEncoder.MODE_DIGIT ? 4 : 5;
// Shifts exist only to UPPER and PUNCT, both with tokens size 5.
token = token.add(HighLevelEncoder.SHIFT_TABLE[this.mode][mode], thisModeBitCount);
token = token.add(value, 5);
return new State(token, this.mode, 0, this.bitCount + thisModeBitCount + 5);
}
// Create a new state representing this state, but an additional character
// output in Binary Shift mode.
State addBinaryShiftChar(int index) {
Token token = this.token;
int mode = this.mode;
int bitCount = this.bitCount;
if (this.mode == HighLevelEncoder.MODE_PUNCT || this.mode == HighLevelEncoder.MODE_DIGIT) {
int latch = HighLevelEncoder.LATCH_TABLE[mode][HighLevelEncoder.MODE_UPPER];
token = token.add(latch & 0xFFFF, latch >> 16);
bitCount += latch >> 16;
mode = HighLevelEncoder.MODE_UPPER;
}
int deltaBitCount =
(binaryShiftByteCount == 0 || binaryShiftByteCount == 31) ? 18 :
(binaryShiftByteCount == 62) ? 9 : 8;
State result = new State(token, mode, binaryShiftByteCount + 1, bitCount + deltaBitCount);
if (result.binaryShiftByteCount == 2047 + 31) {
// The string is as long as it's allowed to be. We should end it.
result = result.endBinaryShift(index + 1);
}
return result;
}
// Create the state identical to this one, but we are no longer in
// Binary Shift mode.
State endBinaryShift(int index) {
if (binaryShiftByteCount == 0) {
return this;
}
Token token = this.token;
token = token.addBinaryShift(index - binaryShiftByteCount, binaryShiftByteCount);
return new State(token, mode, 0, this.bitCount);
}
// Returns true if "this" state is better (or equal) to be in than "that"
// state under all possible circumstances.
boolean isBetterThanOrEqualTo(State other) {
int newModeBitCount = this.bitCount + (HighLevelEncoder.LATCH_TABLE[this.mode][other.mode] >> 16);
if (this.binaryShiftByteCount < other.binaryShiftByteCount) {
// add additional B/S encoding cost of other, if any
newModeBitCount += other.binaryShiftCost - this.binaryShiftCost;
} else if (this.binaryShiftByteCount > other.binaryShiftByteCount && other.binaryShiftByteCount > 0) {
// maximum possible additional cost (we end up exceeding the 31 byte boundary and other state can stay beneath it)
newModeBitCount += 10;
}
return newModeBitCount <= other.bitCount;
}
BitArray toBitArray(byte[] text) {
List symbols = new ArrayList<>();
for (Token token = endBinaryShift(text.length).token; token != null; token = token.getPrevious()) {
symbols.add(token);
}
BitArray bitArray = new BitArray();
// Add each token to the result in forward order
for (int i = symbols.size() - 1; i >= 0; i--) {
symbols.get(i).appendTo(bitArray, text);
}
return bitArray;
}
@Override
public String toString() {
return String.format("%s bits=%d bytes=%d", HighLevelEncoder.MODE_NAMES[mode], bitCount, binaryShiftByteCount);
}
private static int calculateBinaryShiftCost(int binaryShiftByteCount) {
if (binaryShiftByteCount > 62) {
return 21; // B/S with extended length
}
if (binaryShiftByteCount > 31) {
return 20; // two B/S
}
if (binaryShiftByteCount > 0) {
return 10; // one B/S
}
return 0;
}
}