Add release notes wrt #865, minor post-merge tweaks

Author: cowtowncoder

release-notes/CREDITS-2.x

@@ -196,6 +196,8 @@ Philippe Marschall (marschall@github)
   (2.10.0)
   * Contributed #798: Avoid copy when parsing `BigDecimal`
   (2.14.0)
+  * Contributed #865: Optimize parsing 19 digit longs
+  (2.15.0)
 
 David Nault (dnault@github)
   * Reported #531: Non-blocking parser reports incorrect locations when fed with

release-notes/VERSION-2.x

@@ -21,6 +21,8 @@ JSON library.
 #851: Add `StreamReadFeature.USE_FAST_BIG_DECIMAL_PARSER` to enable
   faster `BigDecimal`, `BigInteger` parsing
  (contributed by @pjfanning)
+#865: Optimize parsing 19 digit longs
+ (contributed by Phillipe M)
 - Build uses package type "jar" but still produces valid OSGi bundle
  (changed needed to keep class timestamps with Reproducible Build)
 

src/main/java/com/fasterxml/jackson/core/base/ParserBase.java

@@ -883,6 +883,19 @@ protected void _parseNumericValue(int expType) throws IOException
                 _numTypesValid = NR_LONG;
                 return;
             }
+            // For [core#865]: handle remaining 19-char cases as well
+            if (len == 19) {
+                char[] buf = _textBuffer.getTextBuffer();
+                int offset = _textBuffer.getTextOffset();
+                if (_numberNegative) {
+                    ++offset;
+                }
+                if (NumberInput.inLongRange(buf, offset, len, _numberNegative)) {
+                    _numberLong = NumberInput.parseLong19(buf, offset, _numberNegative);
+                    _numTypesValid = NR_LONG;
+                    return;
+                }
+            }
             _parseSlowInt(expType);
             return;
         }
@@ -956,35 +969,22 @@ private void _parseSlowFloat(int expType) throws IOException
 
     private void _parseSlowInt(int expType) throws IOException
     {
+        final String numStr = _textBuffer.contentsAsString();
         try {
-            int len = _intLength;
-            char[] buf = _textBuffer.getTextBuffer();
-            int offset = _textBuffer.getTextOffset();
-            if (_numberNegative) {
-                ++offset;
+            // 16-Oct-2018, tatu: Need to catch "too big" early due to [jackson-core#488]
+            if ((expType == NR_INT) || (expType == NR_LONG)) {
+                _reportTooLongIntegral(expType, numStr);
             }
-            // Some long cases still...
-            if (NumberInput.inLongRange(buf, offset, len, _numberNegative)) {
-                _numberLong = NumberInput.parseLong19(buf, offset, _numberNegative);
-                _numTypesValid = NR_LONG;
+            if ((expType == NR_DOUBLE) || (expType == NR_FLOAT)) {
+                _numberDouble = NumberInput.parseDouble(numStr, isEnabled(Feature.USE_FAST_DOUBLE_PARSER));
+                _numTypesValid = NR_DOUBLE;
             } else {
-                String numStr = _textBuffer.contentsAsString();
-                // 16-Oct-2018, tatu: Need to catch "too big" early due to [jackson-core#488]
-                if ((expType == NR_INT) || (expType == NR_LONG)) {
-                    _reportTooLongIntegral(expType, numStr);
-                }
-                if ((expType == NR_DOUBLE) || (expType == NR_FLOAT)) {
-                    _numberDouble = NumberInput.parseDouble(numStr, isEnabled(Feature.USE_FAST_DOUBLE_PARSER));
-                    _numTypesValid = NR_DOUBLE;
-                } else {
-                    // nope, need the heavy guns... (rare case) - since Jackson v2.14, BigInteger parsing is lazy
-                    _numberBigInt = null;
-                    _numberString = numStr;
-                    _numTypesValid = NR_BIGINT;
-                }
+                // nope, need the heavy guns... (rare case) - since Jackson v2.14, BigInteger parsing is lazy
+                _numberBigInt = null;
+                _numberString = numStr;
+                _numTypesValid = NR_BIGINT;
             }
         } catch (NumberFormatException nex) {
-            String numStr = _textBuffer.contentsAsString();
             // Can this ever occur? Due to overflow, maybe?
             _wrapError("Malformed numeric value ("+_longNumberDesc(numStr)+")", nex);
         }

src/main/java/com/fasterxml/jackson/core/io/NumberInput.java

@@ -167,10 +167,12 @@ public static long parseLong(char[] ch, int off, int len)
      * @param off Offset of the first digit character in buffer
      * @param negative Whether original number had a minus sign
      * @return Decoded {@code long} value
+     *
+     * @since 2.15.0
      */
     public static long parseLong19(char[] ch, int off, boolean negative)
     {
-        // Note: caller must ensure length is [10, 18]
+        // Note: caller must ensure length is 19
         long num = 0L;
         for (int i = 0; i < 19; i++) {
             char c = ch[off + i];