Allocations optimization for converters

quickfixj-core/src/main/java/quickfix/NumbersCache.java

@@ -0,0 +1,74 @@
+/*******************************************************************************
+ * Copyright (c) quickfixengine.org  All rights reserved.
+ *
+ * This file is part of the QuickFIX FIX Engine
+ *
+ * This file may be distributed under the terms of the quickfixengine.org
+ * license as defined by quickfixengine.org and appearing in the file
+ * LICENSE included in the packaging of this file.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING
+ * THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE.
+ *
+ * See http://www.quickfixengine.org/LICENSE for licensing information.
+ *
+ * Contact ask@quickfixengine.org if any conditions of this licensing
+ * are not clear to you.
+ ******************************************************************************/
+
+package quickfix;
+
+import java.util.ArrayList;
+
+/**
+ * A cache for commonly used string representing numbers.
+ * Hold values from 0 to 999999 and from 1000 to 200 000 000 by step of 1000
+ */
+public final class NumbersCache {
+
+    private static final int littleNumbersLength = 1000000;
+    private static final int bigNumbersLength = 200000;
+    private static final int bigNumbersOffset = 1000;
+    private static final int bigNumbersMax = bigNumbersLength * bigNumbersOffset;
+
+    public static final ArrayList<String> littleNumbers;
+    public static final ArrayList<String> bigNumbers;
+
+    static {
+        littleNumbers = new ArrayList<String>(littleNumbersLength);
+        bigNumbers = new ArrayList<String>(bigNumbersLength);
+        for (int i = 0; i < littleNumbersLength; i++)
+            littleNumbers.add(Integer.toString(i));
+        for (long i = 0; i < bigNumbersLength;)
+            bigNumbers.add(Long.toString(++i * bigNumbersOffset));
+
+    }
+
+    /**
+     * Get the string representing the given number
+     *
+     * @param i the long to convert
+     * @return the String representing the long
+     */
+    public static String get(long i) {
+        if (i < littleNumbersLength)
+            return littleNumbers.get((int)i);
+        if (i <= bigNumbersMax && i % bigNumbersOffset == 0)
+            return bigNumbers.get((int)(i/bigNumbersOffset)-1);
+        return String.valueOf(i);
+    }
+
+    /**
+     * Get the string representing the given double if it's an integer
+     *
+     * @param d the double to convert
+     * @return the String representing the double or null if the double is not an integer
+     */
+    public static String get(double d) {
+        long l = (long)d;
+        if (d == (double)l)
+            return get(l);
+        return null;
+    }
+}

quickfixj-core/src/main/java/quickfix/field/converter/AbstractDateTimeConverter.java

@@ -21,6 +21,7 @@
 
 import java.text.DateFormat;
 import java.text.DateFormatSymbols;
+import java.text.FieldPosition;
 import java.text.SimpleDateFormat;
 import java.util.Locale;
 import java.util.TimeZone;
@@ -56,18 +57,31 @@ protected static void throwFieldConvertError(String value, String type)
     }
 
     protected static long parseLong(String s) {
+        return parseLong(s, 0, s.length());
+    }
+
+    protected static long parseLong(String s, int begin, int end) {
         long n = 0;
-        for (int i = 0; i < s.length(); i++) {
+        for (int i = begin; i < end; i++) {
             n = (n * 10) + (s.charAt(i) - '0');
         }
         return n;
     }
 
-    protected DateFormat createDateFormat(String format) {
+    protected static DateFormat createDateFormat(String format) {
         SimpleDateFormat sdf = new SimpleDateFormat(format);
         sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
         sdf.setDateFormatSymbols(new DateFormatSymbols(Locale.US));
         return sdf;
     }
 
+    static final class DontCareFieldPosition extends FieldPosition {
+        // The singleton of DontCareFieldPosition.
+        static final FieldPosition INSTANCE = new DontCareFieldPosition();
+
+        private DontCareFieldPosition() {
+            super(0);
+        }
+    }
+
 }

quickfixj-core/src/main/java/quickfix/field/converter/CharConverter.java

@@ -26,6 +26,13 @@
  */
 public class CharConverter {
 
+    private static final String characters[] = new String[Character.MAX_VALUE+1];
+
+    static {
+        for(int c = Character.MAX_VALUE+1; c-- != 0;)
+            characters[c] = String.valueOf(c);
+    }
+
     /**
      * Converts a character to a String
      *
@@ -34,7 +41,7 @@ public class CharConverter {
      * @see java.lang.Character#toString(char)
      */
     public static String convert(char c) {
-        return Character.toString(c);
+        return characters[c];
     }
 
     /**

quickfixj-core/src/main/java/quickfix/field/converter/DoubleConverter.java

@@ -22,18 +22,23 @@
 import java.text.DecimalFormat;
 import java.text.DecimalFormatSymbols;
 import java.util.Locale;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
+import quickfix.CharSequenceReader;
 import quickfix.FieldConvertError;
+import quickfix.NumbersCache;
 import quickfix.RuntimeError;
 
 /**
  * Converts between a double and a String.
  */
 public class DoubleConverter {
-    private static final Pattern decimalPattern = Pattern.compile("-?\\d*(\\.\\d*)?");
-    private static final ThreadLocal<DecimalFormat[]> threadDecimalFormats = new ThreadLocal<DecimalFormat[]>();
+
+    private static final ThreadLocal<DecimalFormat[]> threadDecimalFormats = new ThreadLocal<DecimalFormat[]>() {
+        @Override
+        protected DecimalFormat[] initialValue() {
+            return new DecimalFormat[14];
+        }
+    };
 
     /**
      * Converts a double to a string with no padding.
@@ -52,10 +57,6 @@ static DecimalFormat getDecimalFormat(int padding) {
             throw new RuntimeError("maximum padding of 14 zeroes is supported: " + padding);
         }
         DecimalFormat[] decimalFormats = threadDecimalFormats.get();
-        if (decimalFormats == null) {
-            decimalFormats = new DecimalFormat[14];
-            threadDecimalFormats.set(decimalFormats);
-        }
         DecimalFormat f = decimalFormats[padding];
         if (f == null) {
             StringBuilder buffer = new StringBuilder("0.");
@@ -80,7 +81,8 @@ static DecimalFormat getDecimalFormat(int padding) {
      * @return the formatted String representing the double.
      */
     public static String convert(double d, int padding) {
-        return getDecimalFormat(padding).format(d);
+        String value = NumbersCache.get(d);
+        return null != value ? value : getDecimalFormat(padding).format(d);
     }
 
     /**
@@ -92,11 +94,7 @@ public static String convert(double d, int padding) {
      */
     public static double convert(String value) throws FieldConvertError {
         try {
-            Matcher matcher = decimalPattern.matcher(value);
-            if (!matcher.matches()) {
-                throw new NumberFormatException();
-            }
-            return Double.parseDouble(value);
+            return CharSequenceReader.valueOf(value);
         } catch (NumberFormatException e) {
             throw new FieldConvertError("invalid double value: " + value);
         }

quickfixj-core/src/main/java/quickfix/field/converter/IntConverter.java

@@ -20,6 +20,7 @@
 package quickfix.field.converter;
 
 import quickfix.FieldConvertError;
+import quickfix.NumbersCache;
 
 /**
  * Convert between an integer and a String
@@ -34,7 +35,7 @@ public final class IntConverter {
      * @see java.lang.Long#toString(long)
      */
     public static String convert(int i) {
-        return Long.toString(i);
+        return NumbersCache.get(i);
     }
 
     /**

quickfixj-core/src/main/java/quickfix/field/converter/UtcDateOnlyConverter.java

@@ -29,10 +29,20 @@
  * Convert between a date and a String
  */
 public class UtcDateOnlyConverter extends AbstractDateTimeConverter {
+
+    protected static final class Context {
+        private final DateFormat dateFormat = createDateFormat("yyyyMMdd");
+        private final StringBuffer buffer = new StringBuffer(128);
+    }
+
     // SimpleDateFormats are not thread safe. A thread local is being
     // used to maintain high concurrency among multiple session threads
-    private static final ThreadLocal<UtcDateOnlyConverter> utcDateConverter = new ThreadLocal<UtcDateOnlyConverter>();
-    private final DateFormat dateFormat = createDateFormat("yyyyMMdd");
+    private static final ThreadLocal<Context> utcDateConverter = new ThreadLocal<Context>() {
+        @Override
+        protected Context initialValue() {
+            return new Context();
+        }
+    };
 
     /**
      * Convert a date to a String ("YYYYMMDD")
@@ -41,16 +51,29 @@ public class UtcDateOnlyConverter extends AbstractDateTimeConverter {
      * @return the formatted date
      */
     public static String convert(Date d) {
-        return getFormatter().format(d);
+        Context context = utcDateConverter.get();
+        try {
+            context.dateFormat.format(d, context.buffer, DontCareFieldPosition.INSTANCE);
+            return context.buffer.toString();
+        } finally {
+            context.buffer.setLength(0);
+        }
     }
 
-    private static DateFormat getFormatter() {
-        UtcDateOnlyConverter converter = utcDateConverter.get();
-        if (converter == null) {
-            converter = new UtcDateOnlyConverter();
-            utcDateConverter.set(converter);
+    /**
+     * Convert a date to a String ("YYYYMMDD")
+     *
+     * @param d the date to convert
+     * @param stringBuilder the out buffer to hold formatted date
+     */
+    public static void convert(Date d, StringBuilder stringBuilder) {
+        Context context = utcDateConverter.get();
+        try {
+            context.dateFormat.format(d, context.buffer, DontCareFieldPosition.INSTANCE);
+            stringBuilder.append(context.buffer);
+        } finally {
+            context.buffer.setLength(0);
         }
-        return converter.dateFormat;
     }
 
     /**
@@ -66,7 +89,7 @@ public static Date convert(String value) throws FieldConvertError {
         assertLength(value, 8, type);
         assertDigitSequence(value, 0, 8, type);
         try {
-            d = getFormatter().parse(value);
+            d = utcDateConverter.get().dateFormat.parse(value);
         } catch (ParseException e) {
             throwFieldConvertError(value, type);
         }

quickfixj-core/src/main/java/quickfix/field/converter/UtcTimeOnlyConverter.java

@@ -29,11 +29,21 @@
  * Convert between a time and a String.
  */
 public class UtcTimeOnlyConverter extends AbstractDateTimeConverter {
+
+    protected static final class Context {
+        private final DateFormat utcTimeFormat = createDateFormat("HH:mm:ss");
+        private final DateFormat utcTimeFormatMillis = createDateFormat("HH:mm:ss.SSS");
+        private final StringBuffer buffer = new StringBuffer(128);
+    }
+
     // SimpleDateFormats are not thread safe. A thread local is being
     // used to maintain high concurrency among multiple session threads
-    private static final ThreadLocal<UtcTimeOnlyConverter> utcTimeConverter = new ThreadLocal<UtcTimeOnlyConverter>();
-    private final DateFormat utcTimeFormat = createDateFormat("HH:mm:ss");
-    private final DateFormat utcTimeFormatMillis = createDateFormat("HH:mm:ss.SSS");
+    private static final ThreadLocal<Context> utcTimeConverter = new ThreadLocal<Context>() {
+        @Override
+        protected Context initialValue() {
+            return new Context();
+        }
+    };
 
     /**
      * Convert a time (represented as a Date) to a String (HH:MM:SS or HH:MM:SS.SSS)
@@ -43,15 +53,36 @@ public class UtcTimeOnlyConverter extends AbstractDateTimeConverter {
      * @return a String representing the time.
      */
     public static String convert(Date d, boolean includeMilliseconds) {
-        return getFormatter(includeMilliseconds).format(d);
+        Context context = utcTimeConverter.get();
+        try {
+            (includeMilliseconds ? context.utcTimeFormatMillis : context.utcTimeFormat)
+                    .format(d, context.buffer, DontCareFieldPosition.INSTANCE);
+            return context.buffer.toString();
+        } finally {
+            context.buffer.setLength(0);
+        }
     }
 
-    private static DateFormat getFormatter(boolean includeMillis) {
-        UtcTimeOnlyConverter converter = utcTimeConverter.get();
-        if (converter == null) {
-            converter = new UtcTimeOnlyConverter();
-            utcTimeConverter.set(converter);
+    /**
+     * Convert a time (represented as a Date) to a String (HH:MM:SS or HH:MM:SS.SSS)
+     *
+     * @param d the date with the time to convert
+     * @param includeMilliseconds controls whether milliseconds are included in the result
+     * @param stringBuilder the out buffer to hold a String representing the time.
+     */
+    public static void convert(Date d, StringBuilder stringBuilder, boolean includeMilliseconds) {
+        Context context = utcTimeConverter.get();
+        try {
+            (includeMilliseconds ? context.utcTimeFormatMillis : context.utcTimeFormat)
+                    .format(d, context.buffer, DontCareFieldPosition.INSTANCE);
+            stringBuilder.append(context.buffer);
+        } finally {
+            context.buffer.setLength(0);
         }
+    }
+
+    private static DateFormat getFormatter(boolean includeMillis) {
+        Context converter = utcTimeConverter.get();
         return includeMillis ? converter.utcTimeFormatMillis : converter.utcTimeFormat;
     }