Minor code tweaks

This commit is contained in:
Sean Owen 2021-10-21 23:38:11 -05:00
parent 2e22d09479
commit 6c034f9775
2 changed files with 25 additions and 32 deletions

1
.gitignore vendored
View file

@ -1,3 +1,4 @@
dependency-reduced-pom.xml
target target
.idea .idea
*.iml *.iml

View file

@ -126,8 +126,8 @@ final class MinimalEncoder {
* *
* @param stringToEncode The string to encode * @param stringToEncode The string to encode
* @param priorityCharset The preferred {@link Charset}. When the value of the argument is null, the algorithm * @param priorityCharset The preferred {@link Charset}. When the value of the argument is null, the algorithm
* chooses charsets that leads to a minimal representation. Otherwise the algorithm will use the priority * chooses charsets that leads to a minimal representation. Otherwise the algorithm will use the priority
* charset to encode any character in the input that can be encoded by it if the charset is among the * charset to encode any character in the input that can be encoded by it if the charset is among the
* supported charsets. * supported charsets.
* @param isGS1 {@code true} if a FNC1 is to be prepended; {@code false} otherwise * @param isGS1 {@code true} if a FNC1 is to be prepended; {@code false} otherwise
* @param ecLevel The error correction level. * @param ecLevel The error correction level.
@ -169,8 +169,7 @@ final class MinimalEncoder {
} }
if (neededEncoders.size() == 1 && !needUnicodeEncoder) { if (neededEncoders.size() == 1 && !needUnicodeEncoder) {
encoders = new CharsetEncoder[1]; encoders = new CharsetEncoder[] { neededEncoders.get(0) };
encoders[0] = neededEncoders.get(0);
} else { } else {
encoders = new CharsetEncoder[neededEncoders.size() + 2]; encoders = new CharsetEncoder[neededEncoders.size() + 2];
int index = 0; int index = 0;
@ -185,7 +184,7 @@ final class MinimalEncoder {
int priorityEncoderIndexValue = -1; int priorityEncoderIndexValue = -1;
if (priorityCharset != null) { if (priorityCharset != null) {
for (int i = 0; i < encoders.length; i++) { for (int i = 0; i < encoders.length; i++) {
if (priorityCharset.name().equals(encoders[i].charset().name())) { if (encoders[i] != null && priorityCharset.name().equals(encoders[i].charset().name())) {
priorityEncoderIndexValue = i; priorityEncoderIndexValue = i;
break; break;
} }
@ -198,11 +197,11 @@ final class MinimalEncoder {
* Encodes the string minimally * Encodes the string minimally
* *
* @param stringToEncode The string to encode * @param stringToEncode The string to encode
* @param version The preferred {@link Version}. A minimal version is computed (see * @param version The preferred {@link Version}. A minimal version is computed (see
* {@link ResultList#getVersion method} when the value of the argument is null * {@link ResultList#getVersion method} when the value of the argument is null
* @param priorityCharset The preferred {@link Charset}. When the value of the argument is null, the algorithm * @param priorityCharset The preferred {@link Charset}. When the value of the argument is null, the algorithm
* chooses charsets that leads to a minimal representation. Otherwise the algorithm will use the priority * chooses charsets that leads to a minimal representation. Otherwise the algorithm will use the priority
* charset to encode any character in the input that can be encoded by it if the charset is among the * charset to encode any character in the input that can be encoded by it if the charset is among the
* supported charsets. * supported charsets.
* @param isGS1 {@code true} if a FNC1 is to be prepended; {@code false} otherwise * @param isGS1 {@code true} if a FNC1 is to be prepended; {@code false} otherwise
* @param ecLevel The error correction level. * @param ecLevel The error correction level.
@ -275,15 +274,6 @@ final class MinimalEncoder {
return Encoder.getAlphanumericCode(c) != -1; return Encoder.getAlphanumericCode(c) != -1;
} }
/**
* Returns the maximum number of encodeable characters in the given mode for the given version. Example: in
* Version 1, 2^10 digits or 2^8 bytes can be encoded. In Version 3 it is 2^14 digits and 2^16 bytes
*/
static int getMaximumNumberOfEncodeableCharacters(Version version, Mode mode) {
int count = mode.getCharacterCountBits(version);
return count == 0 ? 0 : 1 << count;
}
boolean canEncode(Mode mode, char c) { boolean canEncode(Mode mode, char c) {
switch (mode) { switch (mode) {
case KANJI: return isDoubleByteKanji(c); case KANJI: return isDoubleByteKanji(c);
@ -383,7 +373,7 @@ final class MinimalEncoder {
* *
* Example 1 encoding the string "ABCDE": * Example 1 encoding the string "ABCDE":
* Note: This example assumes that alphanumeric encoding is only possible in multiples of two characters so that * Note: This example assumes that alphanumeric encoding is only possible in multiples of two characters so that
* the example is both short and showing the principle. In reality this restriction does not exist. * the example is both short and showing the principle. In reality this restriction does not exist.
* *
* Initial situation * Initial situation
* (initial) -- BYTE(A) (20) --> (1_BYTE) * (initial) -- BYTE(A) (20) --> (1_BYTE)
@ -533,9 +523,10 @@ final class MinimalEncoder {
private final int characterLength; private final int characterLength;
private final Edge previous; private final Edge previous;
private final int cachedTotalSize; private final int cachedTotalSize;
private Edge(Mode mode, int fromPosition, int charsetEncoderIndex, int characterLength, Edge previous, private Edge(Mode mode, int fromPosition, int charsetEncoderIndex, int characterLength, Edge previous,
Version version) { Version version) {
this.mode = mode; this.mode = mode;
this.fromPosition = fromPosition; this.fromPosition = fromPosition;
this.charsetEncoderIndex = mode == Mode.BYTE || previous == null ? charsetEncoderIndex : this.charsetEncoderIndex = mode == Mode.BYTE || previous == null ? charsetEncoderIndex :
previous.charsetEncoderIndex; // inherit the encoding if not of type BYTE previous.charsetEncoderIndex; // inherit the encoding if not of type BYTE
@ -573,9 +564,10 @@ final class MinimalEncoder {
} }
} }
final class ResultList extends ArrayList<ResultList.ResultNode> { final class ResultList {
final Version version; private final List<ResultList.ResultNode> list = new ArrayList<>();
private final Version version;
ResultList(Version version, Edge solution) { ResultList(Version version, Edge solution) {
int length = 0; int length = 0;
@ -595,12 +587,12 @@ final class MinimalEncoder {
} }
if (previous == null || previous.mode != current.mode || needECI) { if (previous == null || previous.mode != current.mode || needECI) {
add(0, new ResultNode(current.mode, current.fromPosition, current.charsetEncoderIndex, length)); list.add(0, new ResultNode(current.mode, current.fromPosition, current.charsetEncoderIndex, length));
length = 0; length = 0;
} }
if (needECI) { if (needECI) {
add(0, new ResultNode(Mode.ECI, current.fromPosition, current.charsetEncoderIndex, 0)); list.add(0, new ResultNode(Mode.ECI, current.fromPosition, current.charsetEncoderIndex, 0));
} }
current = previous; current = previous;
} }
@ -608,16 +600,16 @@ final class MinimalEncoder {
// prepend FNC1 if needed. If the bits contain an ECI then the FNC1 must be preceeded by an ECI. // prepend FNC1 if needed. If the bits contain an ECI then the FNC1 must be preceeded by an ECI.
// If there is no ECI at the beginning then we put an ECI to the default charset (ISO-8859-1) // If there is no ECI at the beginning then we put an ECI to the default charset (ISO-8859-1)
if (isGS1) { if (isGS1) {
ResultNode first = get(0); ResultNode first = list.get(0);
if (first != null && first.mode != Mode.ECI && containsECI) { if (first != null && first.mode != Mode.ECI && containsECI) {
// prepend a default character set ECI // prepend a default character set ECI
add(0, new ResultNode(Mode.ECI, 0, 0, 0)); list.add(0, new ResultNode(Mode.ECI, 0, 0, 0));
} }
first = get(0); first = list.get(0);
// prepend or insert a FNC1_FIRST_POSITION after the ECI (if any) // prepend or insert a FNC1_FIRST_POSITION after the ECI (if any)
add(first.mode != Mode.ECI ? 0 : 1, new ResultNode(Mode.FNC1_FIRST_POSITION, 0, 0, 0)); list.add(first.mode != Mode.ECI ? 0 : 1, new ResultNode(Mode.FNC1_FIRST_POSITION, 0, 0, 0));
} }
// set version to smallest version into which the bits fit. // set version to smallest version into which the bits fit.
int versionNumber = version.getVersionNumber(); int versionNumber = version.getVersionNumber();
int lowerLimit; int lowerLimit;
@ -660,7 +652,7 @@ final class MinimalEncoder {
private int getSize(Version version) { private int getSize(Version version) {
int result = 0; int result = 0;
for (ResultNode resultNode : this) { for (ResultNode resultNode : list) {
result += resultNode.getSize(version); result += resultNode.getSize(version);
} }
return result; return result;
@ -670,7 +662,7 @@ final class MinimalEncoder {
* appends the bits * appends the bits
*/ */
void getBits(BitArray bits) throws WriterException { void getBits(BitArray bits) throws WriterException {
for (ResultNode resultNode : this) { for (ResultNode resultNode : list) {
resultNode.getBits(bits); resultNode.getBits(bits);
} }
} }
@ -682,7 +674,7 @@ final class MinimalEncoder {
public String toString() { public String toString() {
StringBuilder result = new StringBuilder(); StringBuilder result = new StringBuilder();
ResultNode previous = null; ResultNode previous = null;
for (ResultNode current : this) { for (ResultNode current : list) {
if (previous != null) { if (previous != null) {
result.append(","); result.append(",");
} }