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string performance optimisation #102

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53 changes: 37 additions & 16 deletions src/main/java/com/dashjoin/jsonata/Functions.java
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Original file line number Diff line number Diff line change
Expand Up @@ -609,10 +609,11 @@ public static String leftPad(final String str, final int size, String padStr) {
if (pads <= 0) {
return str;
}
String padding = "";
StringBuilder paddingSb = new StringBuilder();
for (int i = 0; i < pads + 1; i++) {
padding += padStr;
paddingSb.append(padStr);
}
String padding = paddingSb.toString();
return substr(padding, 0, pads).concat(str);
}

Expand All @@ -638,10 +639,11 @@ public static String rightPad(final String str, final int size, String padStr) {
if (pads <= 0) {
return str;
}
String padding = "";
StringBuilder paddingSb = new StringBuilder();
for (int i = 0; i < pads + 1; i++) {
padding += padStr;
paddingSb.append(padStr);
}
String padding = paddingSb.toString();
return str.concat(substr(padding, 0, pads));
}

Expand Down Expand Up @@ -770,14 +772,21 @@ public static String join(List<String> strs, String separator) {
return String.join(separator, strs);
}

private static final Pattern DOLLAR_DOLLAR = Pattern.compile("\\$\\$");
private static final Pattern DOLLAR_WITHOUT_ESCAPE = Pattern.compile("([^\\\\]|^)\\$([^0-9^<])");
private static final Pattern DOLLAR_AT_END = Pattern.compile("\\$$");
static String safeReplacement(String in) {
// In JSONata and in Java the $ in the replacement test usually starts the insertion of a capturing group
// In order to replace a simple $ in Java you have to escape the $ with "\$"
// in JSONata you do this with a '$$'
// "\$" followed any character besides '<' and and digit into $ + this character
return in.replaceAll("\\$\\$", "\\\\\\$")
.replaceAll("([^\\\\]|^)\\$([^0-9^<])", "$1\\\\\\$$2")
.replaceAll("\\$$", "\\\\\\$"); // allow $ at end
// "\$" followed any character besides '<' and and digit into $ + this character
if (!in.contains("$")) {
return in;
}
String result = DOLLAR_DOLLAR.matcher(in).replaceAll("\\\\\\$");
result = DOLLAR_WITHOUT_ESCAPE.matcher(result).replaceAll("$1\\\\\\$$2");
result = DOLLAR_AT_END.matcher(result).replaceAll("\\\\\\$");
return result;
}

/**
Expand Down Expand Up @@ -963,6 +972,12 @@ public static String base64decode(String str) {
}
}

private static final Pattern PLUS = Pattern.compile("\\+");
private static final Pattern PERCENT_21 = Pattern.compile("%21");
private static final Pattern PERCENT_27 = Pattern.compile("%27");
private static final Pattern PERCENT_28 = Pattern.compile("%28");
private static final Pattern PERCENT_29 = Pattern.compile("%29");
private static final Pattern PERCENT_7E = Pattern.compile("%7E");
/**
* Encode a string into a component for a url
* @param {String} str - String to encode
Expand All @@ -975,14 +990,20 @@ public static String encodeUrlComponent(String str) {
}

Utils.checkUrl(str);

return URLEncoder.encode(str, StandardCharsets.UTF_8)
.replaceAll("\\+", "%20")
.replaceAll("\\%21", "!")
.replaceAll("\\%27", "'")
.replaceAll("\\%28", "(")
.replaceAll("\\%29", ")")
.replaceAll("\\%7E", "~");

String encoded = URLEncoder.encode(str, StandardCharsets.UTF_8);

if (!encoded.contains("+") && !encoded.contains("%")) {
return encoded;
}

encoded = PLUS.matcher(encoded).replaceAll("%20");
encoded = PERCENT_21.matcher(encoded).replaceAll("!");
encoded = PERCENT_27.matcher(encoded).replaceAll("'");
encoded = PERCENT_28.matcher(encoded).replaceAll("(");
encoded = PERCENT_29.matcher(encoded).replaceAll(")");
encoded = PERCENT_7E.matcher(encoded).replaceAll("~");
return encoded;
}

/**
Expand Down
5 changes: 3 additions & 2 deletions src/main/java/com/dashjoin/jsonata/Parser.java
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Original file line number Diff line number Diff line change
Expand Up @@ -590,17 +590,18 @@ Symbol led(Symbol left) {
// is the next token a '<' - if so, parse the function signature
if (node.id.equals("<")) {
int depth = 1;
String sig = "<";
StringBuilder sigBuilder = new StringBuilder("<");
while (depth > 0 && !node.id.equals("{") && !node.id.equals("(end)")) {
Symbol tok = advance();
if (tok.id.equals(">")) {
depth--;
} else if (tok.id.equals("<")) {
depth++;
}
sig += tok.value;
sigBuilder.append(tok.value);
}
advance(">");
String sig = sigBuilder.toString();
this.signature = new Signature(sig, "lambda");
}
// parse the function body
Expand Down
14 changes: 7 additions & 7 deletions src/main/java/com/dashjoin/jsonata/Tokenizer.java
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Original file line number Diff line number Diff line change
Expand Up @@ -83,6 +83,7 @@ public class Tokenizer { // = function (path) {
put("t", "\t");
}};

private static final Pattern NUM_REGEX = Pattern.compile("^-?(0|([1-9][0-9]*))(\\.[0-9]+)?([Ee][-+]?[0-9]+)?");
// Tokenizer (lexer) - invoked by the parser to return one token at a time
String path;
int position = 0;
Expand Down Expand Up @@ -262,20 +263,20 @@ Token next(boolean prefix) {
char quoteType = currentChar;
// double quoted string literal - find end of string
position++;
var qstr = "";
var qstr = new StringBuilder();
while (position < length) {
currentChar = path.charAt(position);
if (currentChar == '\\') { // escape sequence
position++;
if (position < path.length()) currentChar = path.charAt(position); else throw new JException("S0103", position, "");
if (escapes.get(""+currentChar)!=null) {
qstr += escapes.get(""+currentChar);
qstr.append(escapes.get(""+currentChar));
} else if (currentChar == 'u') {
// u should be followed by 4 hex digits
String octets = position+5 < path.length() ? path.substring(position + 1, (position + 1) + 4) : "";
if (octets.matches("^[0-9a-fA-F]+$")) { // /^[0-9a-fA-F]+$/.test(octets)) {
int codepoint = Integer.parseInt(octets, 16);
qstr += Character.toString((char) codepoint);
qstr.append((char) codepoint);
position += 4;
} else {
throw new JException("S0104", position);
Expand All @@ -287,17 +288,16 @@ Token next(boolean prefix) {
}
} else if (currentChar == quoteType) {
position++;
return create("string", qstr);
return create("string", qstr.toString());
} else {
qstr += currentChar;
qstr.append(currentChar);
}
position++;
}
throw new JException("S0101", position);
}
// test for numbers
Pattern numregex = Pattern.compile("^-?(0|([1-9][0-9]*))(\\.[0-9]+)?([Ee][-+]?[0-9]+)?");
Matcher match = numregex.matcher(path.substring(position));
Matcher match = NUM_REGEX.matcher(path.substring(position));
if (match.find()) {
double num = Double.parseDouble(match.group(0));
if (!Double.isNaN(num) && Double.isFinite(num)) {
Expand Down
16 changes: 13 additions & 3 deletions src/main/java/com/dashjoin/jsonata/json/JsonParser.java
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Original file line number Diff line number Diff line change
Expand Up @@ -344,22 +344,32 @@ private void readEscape() throws IOException {
captureBuffer.append('\t');
break;
case 'u':
char[] hexChars = new char[4];
int value = 0;
for (int i = 0; i < 4; i++) {
read();
if (!isHexDigit()) {
throw expected("hexadecimal digit");
}
hexChars[i] = (char)current;
value = (value << 4) | hexCharToValue((char) current);
}
captureBuffer.append((char)Integer.parseInt(new String(hexChars), 16));
captureBuffer.append((char) value);
break;
default:
throw expected("valid escape sequence");
}
read();
}

private int hexCharToValue(char c) {
if (c >= '0' && c <= '9') {
return c - '0';
} else if (c >= 'A' && c <= 'F') {
return c - 'A' + 10;
} else { // c >= 'a' && c <= 'f'
return c - 'a' + 10;
}
}

private void readNumber() throws IOException {
handler.startNumber();
startCapture();
Expand Down
26 changes: 13 additions & 13 deletions src/main/java/com/dashjoin/jsonata/utils/DateTimeUtils.java
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Expand Up @@ -174,9 +174,9 @@ private static String lookup(long num, boolean prev, boolean ord) {
wordValuesLong.put(lword + "th", val);
}
}

private static final Pattern SPLIT_PATTERN = Pattern.compile(",\\s|\\sand\\s|[\\s\\-]");
public static int wordsToNumber(String text) {
String[] parts = text.split(",\\s|\\sand\\s|[\\s\\-]");
String[] parts = SPLIT_PATTERN.split(text);
Integer[] values = new Integer[parts.length];
for (int i = 0; i < parts.length; i++) {
values[i] = wordValues.get(parts[i]);
Expand All @@ -202,7 +202,7 @@ public static int wordsToNumber(String text) {
* long version of above
*/
public static long wordsToLong(String text) {
String[] parts = text.split(",\\s|\\sand\\s|[\\s\\-]");
String[] parts = SPLIT_PATTERN.split(text);
Long[] values = new Long[parts.length];
for (int i = 0; i < parts.length; i++) {
values[i] = wordValuesLong.get(parts[i]);
Expand Down Expand Up @@ -788,16 +788,15 @@ public static String formatDateTime(long millis, String picture, String timezone

int offsetMillis = (60 * offsetHours + offsetMinutes) * 60 * 1000;
LocalDateTime dateTime = LocalDateTime.ofInstant(Instant.ofEpochMilli(millis + offsetMillis), ZoneOffset.UTC);
String result = "";
StringBuilder resultBuilder = new StringBuilder();
for (SpecPart part : formatSpec.parts) {
if (part.type.equals("literal")) {
result += part.value;
resultBuilder.append(part.value);
} else {
result += formatComponent(dateTime, part, offsetHours, offsetMinutes);
resultBuilder.append(formatComponent(dateTime, part, offsetHours, offsetMinutes));
}
}

return result;
return resultBuilder.toString();
}

private static String formatComponent(LocalDateTime date, SpecPart markerSpec, int offsetHours, int offsetMinutes) {
Expand Down Expand Up @@ -938,11 +937,12 @@ private static String getDateTimeFragment(LocalDateTime date, Character componen
public static Long parseDateTime(String timestamp, String picture) {
PictureFormat formatSpec = analyseDateTimePicture(picture);
PictureMatcher matchSpec = generateRegex(formatSpec);
String fullRegex = "^";
StringBuilder fullRegexBuilder = new StringBuilder("^");
for (MatcherPart part : matchSpec.parts) {
fullRegex += "(" + part.regex + ")";
fullRegexBuilder.append("(").append(part.regex).append(")");
}
fullRegex += "$";
fullRegexBuilder.append("$");
String fullRegex = fullRegexBuilder.toString();
Pattern pattern = Pattern.compile(fullRegex, Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(timestamp);
if (matcher.find()) {
Expand Down Expand Up @@ -1060,13 +1060,13 @@ private static boolean isType(int type, int mask) {
return ((~type & mask) == 0) && (type & mask) != 0;
}

private static final Pattern LITERAL_ESCAPE_PATTERN = Pattern.compile("[.*+?^${}()|\\[\\]\\\\]");
private static PictureMatcher generateRegex(PictureFormat formatSpec) {
PictureMatcher matcher = new PictureMatcher();
for (final SpecPart part : formatSpec.parts) {
MatcherPart res;
if (part.type.equals("literal")) {
Pattern p = Pattern.compile("[.*+?^${}()|\\[\\]\\\\]");
Matcher m = p.matcher(part.value);
Matcher m = LITERAL_ESCAPE_PATTERN.matcher(part.value);

String regex = m.replaceAll("\\\\$0");
res = new MatcherPart(regex) {
Expand Down
32 changes: 15 additions & 17 deletions src/main/java/com/dashjoin/jsonata/utils/Signature.java
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Original file line number Diff line number Diff line change
Expand Up @@ -298,13 +298,13 @@ void throwValidationError(List<?> badArgs, String badSig, String functionName) {
@SuppressWarnings({"rawtypes", "unchecked"})
public Object validate(Object _args, Object context) {

var result = new ArrayList<>();

var args = (List)_args;
String suppliedSig = "";
for (Object arg : args)
suppliedSig += getSymbol(arg);

StringBuilder sigBuilder = new StringBuilder(args.size());
for (Object arg : args) {
sigBuilder.append(getSymbol(arg));
}
String suppliedSig = sigBuilder.toString();

Matcher isValid = _regex.matcher(suppliedSig);
if (isValid != null && isValid.matches()) {
var validatedArgs = new ArrayList<>();
Expand Down Expand Up @@ -337,21 +337,21 @@ public Object validate(Object _args, Object context) {
} else {
// may have matched multiple args (if the regex ends with a '+'
// split into single tokens
String[] singles = match.split("");
for (String single : singles) {
char[] singles = match.toCharArray();
for (char single : singles) {
//match.split('').forEach(function (single) {
if (param.type.equals("a")) {
if (single.equals("m")) {
if (single == 'm') {
// missing (undefined)
arg = null;
} else {
arg = argIndex <args.size() ? args.get(argIndex) : null;
var arrayOK = true;
// is there type information on the contents of the array?
if (param.subtype != null) {
if (!single.equals("a") && !match.equals(param.subtype)) {
if (single != 'a' && !match.equals(param.subtype)) {
arrayOK = false;
} else if (single.equals("a")) {
} else if (single == 'a') {
List argArr = (List)arg;
if (argArr.size() > 0) {
var itemType = getSymbol(argArr.get(0));
Expand All @@ -377,24 +377,22 @@ public Object validate(Object _args, Object context) {
);
}
// the function expects an array. If it's not one, make it so
if (!single.equals("a")) {
if (single != 'a') {
List _arg = new ArrayList<>(); _arg.add(arg);
arg = _arg;
}
}
validatedArgs.add(arg);
argIndex++;
} else {
arg = argIndex<args.size() ? args.get(argIndex) : null;
validatedArgs.add(arg);
argIndex++;
}
validatedArgs.add(arg);
argIndex++;
}
}
index++;
}
return validatedArgs;
}
}
throwValidationError(args, suppliedSig, functionName);
return null; // dead code -> compiler happy
}
Expand Down
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