Improvements

Fixed misspelling
Renamed ToDateParams to ToDateParser
Code cleanup

h2/src/main/org/h2/util/DateTimeUtils.java

@@ -10,7 +10,6 @@ package org.h2.util;
 import java.sql.Date;
 import java.sql.Time;
 import java.sql.Timestamp;
-import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.*;
 
@@ -581,59 +580,6 @@ public class DateTimeUtils {
         }
     }
 
-    @SuppressWarnings("serial")
-    private static final Map<String, String> DATE_FORMAT_REGEXPS = new HashMap<String, String>() {
-        {
-            put("^\\d{8}[^\\d]*", "yyyyMMdd");
-            put("^\\d{1,2}\\.\\d{1,2}\\.\\d{4}[^\\d]*", "dd.MM.yyyy");
-            put("^\\d{4}\\.\\d{1,2}\\.\\d{1,2}[^\\d]*", "yyyy.MM.dd");
-            put("^\\d{4}-\\d{1,2}-\\d{1,2}[^\\d]*", "yyyy-MM-dd");
-            put("^\\d{1,2}-\\d{1,2}-\\d{4}[^\\d]*", "dd-MM-yyyy");
-            put("^\\d{1,2}/\\d{1,2}/\\d{4}[^\\d]*", "dd/MM/yyyy");
-            put("^\\d{4}/\\d{1,2}/\\d{1,2}[^\\d]*", "yyyy/MM/dd");
-            put("^\\d{1,2}/\\d{1,2}/\\d{4}[^\\d]*", "dd/MM/yyyy");
-            put("^\\d{1,2}-[^\\d]{3}-\\d{4}[^\\d]*", "dd-MMM-yyyy");
-            put("^\\d{4}-[^\\d]{3}-\\d{1,2}[^\\d]*", "yyyy-MMM-dd");
-            put("^.{2}\\s.{3}\\s\\d{1,2}\\s\\d{1,2}\\:\\d{1,2}\\:\\d{1,2}\\s.{3}\\s\\d{4}$",
-                    "EEE MMM dd hh:mm:ss z yyyy");
-        }
-    };
-
-    /**
-     * Determine SimpleDateFormat pattern matching with the given date string. Returns null if format is unknown. You can
-     * simply extend DateUtil with more formats if needed.
-     *
-     * @param dateString
-     *          The date string to determine the SimpleDateFormat pattern for.
-     * @return The matching SimpleDateFormat pattern, or null if format is unknown.
-     */
-    private static String determineDateFormat(final String dateString) {
-        for (String regexp : DATE_FORMAT_REGEXPS.keySet()) {
-            if (dateString.toLowerCase().matches(regexp)) {
-                return DATE_FORMAT_REGEXPS.get(regexp);
-            }
-        }
-        return null; // Unknown format.
-    }
-
-    /**
-     * Parse date-string in "Best Effort" (BE) manner.
-     * Uses a predefined list of date patterns to parse a string into a date.
-     */
-    public static java.util.Date parseDateBestEffort(final String dateStr) {
-        String dateFormat = determineDateFormat(dateStr);
-        if (dateFormat == null) {
-            // The source does not contain a date that can be parsed.
-            throw DbException.get(ErrorCode.PARSE_ERROR_1, "Invalid date. " + dateStr);
-        }
-        SimpleDateFormat formatter = new SimpleDateFormat(dateFormat);
-        try {
-            return formatter.parse(dateStr);
-        } catch (ParseException e) {
-            throw DbException.get(ErrorCode.PARSE_ERROR_1, e, "Invalid date. " + dateStr);
-        }
-    }
-
     /**
      * Parses a date using a format string.
      *

h2/src/main/org/h2/util/ToDate.java

 package org.h2.util;
 
 import java.sql.Timestamp;
-import java.util.List;
-
-import org.h2.util.ToDateTokenizer.FormatTokenEnum;
+import java.util.Date;
 
 /**
  * Emulates Oracle's TO_DATE function.<br>
  * Main class
  */
 public class ToDate {
-    public enum ToDateFunctionName {
-        TO_DATE("DD MON YYYY"), TO_TIMESTAMP("DD MON YYYY HH:MI:SS");
-
-        private final String defaultFormatStr;
-
-        ToDateFunctionName(final String defaultFormatStr) {
-            this.defaultFormatStr = defaultFormatStr;
-        }
-
-        String getDefaultFormatStr() {
-            return defaultFormatStr;
-        }
-    };
-
     public static Timestamp TO_DATE(final String input, final String format) {
-        ToDateParams parsed = parse(new ToDateParams(ToDateFunctionName.TO_DATE, input, format));
-        return parsed.getResultingTimestamp();
+        ToDateParser parser = ToDateParser.toDate(input, format);
+        return parser.getResultingTimestamp();
     }
-
     public static Timestamp TO_TIMESTAMP(final String input, final String format) {
-        ToDateParams parsed = parse(new ToDateParams(ToDateFunctionName.TO_TIMESTAMP, input, format));
-        return parsed.getResultingTimestamp();
+        ToDateParser parser = ToDateParser.toTimestamp(input, format);
+        return parser.getResultingTimestamp();
     }
-
-    /**
-     * Parse the format-string with passed token of {@link FormatTokenEnum}}.<br>
-     * if token matches return true otherwise false.
-     */
-    private static ToDateParams parse(final ToDateParams p) {
-        while (p.hasToParseData()) {
-            List<FormatTokenEnum> tokenList = FormatTokenEnum.getTokensInQuestion(p);
-            if (tokenList.isEmpty()) {
-                p.removeFirstChar();
-                continue;
-            }
-            boolean foundAnToken = false;
-            for (FormatTokenEnum token : tokenList) {
-                if (token.parseFormatStrWithToken(p)) {
-                    foundAnToken = true;
-                    break;
-                }
-            }
-            if (!foundAnToken) {
-                p.removeFirstChar();
-                continue;
-            }
-        }
-        return p;
-    }
-
 }
\ No newline at end of file

h2/src/main/org/h2/util/ToDateParams.java → h2/src/main/org/h2/util/ToDateParser.java

@@ -2,31 +2,53 @@ package org.h2.util;
 
 import static java.lang.String.format;
 
-import java.sql.Date;
 import java.sql.Timestamp;
 import java.util.Calendar;
-
-import org.h2.util.ToDate.ToDateFunctionName;
+import java.util.Date;
+import java.util.List;
 
 /**
  * Emulates Oracle's TO_DATE function.<br>
  * This class holds and handles the input data form the TO_DATE-method
  */
-class ToDateParams {
+class ToDateParser {
     private final String unmodifiedInputStr;
     private final String unmodifiedFormatStr;
-    private final ToDateFunctionName functionName;
+    private final ConfigParam functionName;
     private String inputStr;
     private String formatStr;
     private final Calendar resultCalendar = (Calendar) Calendar.getInstance().clone();
     private Integer nanos = null;
 
+    private enum ConfigParam {
+        TO_DATE("DD MON YYYY"), TO_TIMESTAMP("DD MON YYYY HH:MI:SS");
+        private final String defaultFormatStr;
+        ConfigParam (final String defaultFormatStr) {
+            this.defaultFormatStr = defaultFormatStr;
+        }
+        String getDefaultFormatStr() {
+            return defaultFormatStr;
+        }
+    }
+
+    static ToDateParser toDate(final String input, final String format) {
+        ToDateParser result = new ToDateParser(ConfigParam.TO_DATE, input, format);
+        parse(result);
+        return result;
+    }
+
+    static ToDateParser toTimestamp(final String input, final String format) {
+        ToDateParser result = new ToDateParser(ConfigParam.TO_TIMESTAMP, input, format);
+        parse(result);
+        return result;
+    }
+
     /**
      * @param input the input date with the date-time info
      * @param format  the format of date-time info
      * @param functionName one of [TO_DATE, TO_TIMESTAMP] (both share the same code)
      */
-    ToDateParams(final ToDateFunctionName functionName, final String input, final String format) {
+    ToDateParser(final ConfigParam functionName, final String input, final String format) {
         // reset calendar - default oracle behaviour
         resultCalendar.set(Calendar.YEAR, 1970);
         resultCalendar.set(Calendar.MONTH, Calendar.getInstance().get(Calendar.MONTH));
@@ -52,10 +74,6 @@ class ToDateParams {
         unmodifiedFormatStr = formatStr; // Keep a copy
     }
 
-    Date getResultingDate() {
-        return new Date(getResultCalendar().getTimeInMillis());
-    }
-
     Timestamp getResultingTimestamp() {
         Calendar cal = (Calendar) getResultCalendar().clone();
         int nanosToSet = nanos == null ? cal.get(Calendar.MILLISECOND) * 1000000 : nanos.intValue();
@@ -77,8 +95,8 @@ class ToDateParams {
         return formatStr;
     }
 
-    ToDateFunctionName getFunctionName() {
-        return functionName;
+    String getFunctionName() {
+        return functionName.name();
     }
 
     void setNanos(final int nanos) {
@@ -98,6 +116,28 @@ class ToDateParams {
         }
     }
 
+    private static ToDateParser parse(final ToDateParser p) {
+        while (p.hasToParseData()) {
+            List<ToDateTokenizer.FormatTokenEnum> tokenList = ToDateTokenizer.FormatTokenEnum.getTokensInQuestion(p.getFormatStr());
+            if (tokenList.isEmpty()) {
+                p.removeFirstChar();
+                continue;
+            }
+            boolean foundAnToken = false;
+            for (ToDateTokenizer.FormatTokenEnum token : tokenList) {
+                if (token.parseFormatStrWithToken(p)) {
+                    foundAnToken = true;
+                    break;
+                }
+            }
+            if (!foundAnToken) {
+                p.removeFirstChar();
+                continue;
+            }
+        }
+        return p;
+    }
+
     void remove(final String toIgnore) {
         if (toIgnore != null) {
             int trimLeng = toIgnore.length();

h2/src/main/org/h2/util/ToDateTokenizer.java

@@ -27,7 +27,6 @@ class ToDateTokenizer {
     private static final Pattern PATTERN_BC_AD = Pattern.compile("^(BC|B\\.C\\.|AD|A\\.D\\.)", Pattern.CASE_INSENSITIVE);
     private static final YearParslet PARSLET_YEAR = new YearParslet();
     private static final MonthParslet PARSLET_MONTH = new MonthParslet();
-    //private static final WeekParslet PARSLET_Week = new WeekParslet();
     private static final DayParslet PARSLET_DAY = new DayParslet();
     private static final TimeParslet PARSLET_TIME = new TimeParslet();
 
@@ -48,8 +47,6 @@ class ToDateTokenizer {
         , MON(PARSLET_MONTH) // Abbreviated name of month.
         , MM(PARSLET_MONTH) // Month (01-12; JAN = 01).
         , RM(PARSLET_MONTH) // Roman numeral month (I-XII; JAN = I).
-        //, WW(PARSLET_Week) // Week of year (1-53)
-        //, IW(PARSLET_Week) // Week of year (1-52 or 1-53) based on the ISO standard.
         , DDD(PARSLET_DAY) // Day of year (1-366).
         , DAY(PARSLET_DAY) // Name of day.
         , DD(PARSLET_DAY) // Day of month (1-31).
@@ -71,7 +68,6 @@ class ToDateTokenizer {
         , Y(PARSLET_YEAR) //
         , I(PARSLET_YEAR) //
         , Q(PARSLET_MONTH) // Quarter of year (1, 2, 3, 4; JAN-MAR = 1).
-        //, W(PARSLET_Week) // Week of month (1-5)
         , D(PARSLET_DAY) // Day of week (1-7).
         , J(PARSLET_DAY); // NOT supported yet - Julian day; the number of days since Jan 1, 4712 BC.
 
@@ -96,12 +92,11 @@ class ToDateTokenizer {
          * OPTIMISATION: Only return a list of {@link FormatTokenEnum} that share the same 1st char
          * using the 1st char of the 'to parse' formatStr. Or return empty list if no match.
          */
-        static List<FormatTokenEnum> getTokensInQuestion(final ToDateParams params) {
+        static List<FormatTokenEnum> getTokensInQuestion(String formatStr) {
             List<FormatTokenEnum> result = EMPTY_LIST;
             if (cache.size() <= 0) {
                 initCache();
             }
-            String formatStr = params.getFormatStr();
             if (formatStr != null && formatStr.length() > 0) {
                 Character key = Character.toUpperCase(formatStr.charAt(0));
                 result = cache.get(key);
@@ -142,9 +137,9 @@ class ToDateTokenizer {
 
         /**
          * Parse the format-string with passed token of {@link FormatTokenEnum}}.<br>
-         * if token matches return true otherwise false.
+         * If token matches return true, otherwise false.
          */
-        boolean parseFormatStrWithToken(final ToDateParams params) {
+        boolean parseFormatStrWithToken(final ToDateParser params) {
             Matcher matcher = patternToUse.matcher(params.getFormatStr());
             boolean foundToken = matcher.find();
             if (foundToken) {
@@ -159,15 +154,15 @@ class ToDateTokenizer {
      * Interface of the classes that can parse a specialized small bit of the TO_DATE format-string
      */
     interface ToDateParslet {
-        ToDateParams parse(ToDateParams params, FormatTokenEnum formatTokenEnum, String formatTokenStr);
+        void parse(ToDateParser params, FormatTokenEnum formatTokenEnum, String formatTokenStr);
     }
 
     /**
-     *
+     * Parslet responsible for parsing year parameter
      */
     private static final class YearParslet implements ToDateParslet {
         @Override
-        public ToDateParams parse(final ToDateParams params, final FormatTokenEnum formatTokenEnum,
+        public void parse(final ToDateParser params, final FormatTokenEnum formatTokenEnum,
                           final String formatTokenStr) {
             final Calendar result = params.getResultCalendar();
             String inputFragmentStr = null;
@@ -241,19 +236,18 @@ class ToDateTokenizer {
                             .getSimpleName(), formatTokenEnum));
             }
             params.remove(inputFragmentStr, formatTokenStr);
-            return params;
         }
     }
 
     /**
-     *
+     * Parslet responsible for parsing month parameter
      */
     private static final class MonthParslet implements ToDateParslet {
-        private static String[] ROMAN_Month = { "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX", "X", "XI",
-                "XII" };
+        private static final String[] ROMAN_Month = { "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX", "X",
+                "XI", "XII" };
 
         @Override
-        public ToDateParams parse(final ToDateParams params, final FormatTokenEnum formatTokenEnum,
+        public void parse(final ToDateParser params, final FormatTokenEnum formatTokenEnum,
                           final String formatTokenStr) {
             final Calendar result = params.getResultCalendar();
             final String s = params.getInputStr();
@@ -288,7 +282,7 @@ class ToDateTokenizer {
                     }
                     if (inputFragmentStr == null || inputFragmentStr.isEmpty()) {
                         throwException(params,
-                                format("Issue happend when parsing token '%s'. Expected one of: %s",
+                                format("Issue happened when parsing token '%s'. Expected one of: %s",
                                         formatTokenEnum.name(), Arrays.toString(ROMAN_Month)));
                     }
                     break;
@@ -297,60 +291,15 @@ class ToDateTokenizer {
                             .getSimpleName(), formatTokenEnum));
             }
             params.remove(inputFragmentStr, formatTokenStr);
-            return params;
         }
     }
 
     /**
-     * Week parsing can be used by TO_CHAR but not by TO_DATE
-     *
-    private static final class WeekParslet implements ToDateParslet {
-        @Override
-        public ToDateParams parse(final ToDateParams params, final FormatTokenEnum formatTokenEnum,
-                                  final String formatTokenStr) {
-            final Calendar result = params.getResultCalendar();
-            String inputFragmentStr = null;
-            int dateNr = 0;
-            switch (formatTokenEnum) {
-                case WW:
-                    inputFragmentStr = matchStringOrDie(PATTERN_TWO_DIGITS_OR_LESS, params, formatTokenEnum);
-                    dateNr = parseInt(inputFragmentStr);
-                    // The first week of the month, as defined by
-                    // getFirstDayOfWeek() and getMinimalDaysInFirstWeek(),
-                    result.set(Calendar.WEEK_OF_YEAR, dateNr);
-                    break;
-                case IW:
-                    inputFragmentStr = matchStringOrDie(PATTERN_TWO_DIGITS_OR_LESS, params, formatTokenEnum);
-                    dateNr = parseInt(inputFragmentStr);
-                    // Build set the calendar to ISO8601 (see
-                    // http://en.wikipedia.org/wiki/ISO_8601_week_number)
-                    result.setMinimalDaysInFirstWeek(4);
-                    result.setFirstDayOfWeek(Calendar.MONDAY);
-                    result.set(Calendar.WEEK_OF_YEAR, dateNr);
-                    break;
-                case W:
-                    inputFragmentStr = matchStringOrDie(PATTERN_ONE_DIGIT, params, formatTokenEnum);
-                    dateNr = parseInt(inputFragmentStr);
-                    // The first week of the month, as defined by
-                    // getFirstDayOfWeek() and getMinimalDaysInFirstWeek(),
-                    result.set(Calendar.WEEK_OF_MONTH, dateNr);
-                    break;
-                default:
-                    throw new IllegalArgumentException(format("%s: Internal Error. Unhandled case: %s", this.getClass()
-                            .getSimpleName(), formatTokenEnum));
-            }
-            params.remove(inputFragmentStr, formatTokenStr);
-            return params;
-        }
-    }
-    */
-
-    /**
-     *
+     * Parslet responsible for parsing day parameter
      */
     private static final class DayParslet implements ToDateParslet {
         @Override
-        public ToDateParams parse(final ToDateParams params, final FormatTokenEnum formatTokenEnum,
+        public void parse(final ToDateParser params, final FormatTokenEnum formatTokenEnum,
                           final String formatTokenStr) {
             final Calendar result = params.getResultCalendar();
             String inputFragmentStr = null;
@@ -391,19 +340,18 @@ class ToDateTokenizer {
                             .getSimpleName(), formatTokenEnum));
             }
             params.remove(inputFragmentStr, formatTokenStr);
-            return params;
         }
     }
 
     private static int MILLIS_in_hour = 60 * 60 * 1000;
 
     /**
-     *
+     * Parslet responsible for parsing time parameter
      */
     private static final class TimeParslet implements ToDateParslet {
 
         @Override
-        public ToDateParams parse(final ToDateParams params, final FormatTokenEnum formatTokenEnum,
+        public void parse(final ToDateParser params, final FormatTokenEnum formatTokenEnum,
                           final String formatTokenStr) {
             final Calendar result = params.getResultCalendar();
             String inputFragmentStr = null;
@@ -495,11 +443,9 @@ class ToDateTokenizer {
                             .getSimpleName(), formatTokenEnum));
             }
             params.remove(inputFragmentStr, formatTokenStr);
-            return params;
         }
     }
 
-    // ========== PRIVATE ===================
     private static int parseInt(final String s) {
         int result = 0;
         if (s.length() > 0 && s.charAt(0) == '+') {
@@ -510,7 +456,7 @@ class ToDateTokenizer {
         return result;
     }
 
-    private static String matchStringOrDie(final Pattern p, final ToDateParams params, final Enum<?> aEnum) {
+    private static String matchStringOrDie(final Pattern p, final ToDateParser params, final Enum<?> aEnum) {
         final String s = params.getInputStr();
         Matcher matcher = p.matcher(s);
         if (!matcher.find()) {
@@ -519,7 +465,7 @@ class ToDateTokenizer {
         return matcher.group(1);
     }
 
-    private static String setByName(final Calendar c, final ToDateParams params, final int field, final int style) {
+    private static String setByName(final Calendar c, final ToDateParser params, final int field, final int style) {
         String inputFragmentStr = null;
         String s = params.getInputStr();
         Map<String, Integer> timeStringMap = c.getDisplayNames(field, style, Locale.getDefault());
@@ -532,16 +478,16 @@ class ToDateTokenizer {
             }
         }
         if (inputFragmentStr == null || inputFragmentStr.isEmpty()) {
-            throwException(params, format("Tryed to parse one of '%s' but failed (may be an internal error?)",
+            throwException(params, format("Tried to parse one of '%s' but failed (may be an internal error?)",
                     timeStringMap.keySet()));
         }
         return inputFragmentStr;
     }
 
-    private static void throwException(final ToDateParams params, final String errorStr) {
+    private static void throwException(final ToDateParser params, final String errorStr) {
         throw DbException.get(
                 ErrorCode.INVALID_TO_DATE_FORMAT,
-                params.getFunctionName().name(),
+                params.getFunctionName(),
                 format(" %s. Details: %s", errorStr, params));
     }