package com.fasterxml.jackson.core.io;

import java.math.BigDecimal;

public final class NumberInput
{
    
Textual representation of a double constant that can cause nasty problems with JDK (see http://www.exploringbinary.com/java-hangs-when-converting-2-2250738585072012e-308).
/** * Textual representation of a double constant that can cause nasty problems * with JDK (see http://www.exploringbinary.com/java-hangs-when-converting-2-2250738585072012e-308). */
public final static String NASTY_SMALL_DOUBLE = "2.2250738585072012e-308";
Constants needed for parsing longs from basic int parsing methods
/** * Constants needed for parsing longs from basic int parsing methods */
final static long L_BILLION = 1000000000; final static String MIN_LONG_STR_NO_SIGN = String.valueOf(Long.MIN_VALUE).substring(1); final static String MAX_LONG_STR = String.valueOf(Long.MAX_VALUE);
Fast method for parsing integers that are known to fit into regular 32-bit signed int type. This means that length is between 1 and 9 digits (inclusive)

Note: public to let unit tests call it

/** * Fast method for parsing integers that are known to fit into * regular 32-bit signed int type. This means that length is * between 1 and 9 digits (inclusive) *<p> * Note: public to let unit tests call it */
public static int parseInt(char[] ch, int off, int len) { int num = ch[off + len - 1] - '0'; switch(len) { case 9: num += (ch[off++] - '0') * 100000000; case 8: num += (ch[off++] - '0') * 10000000; case 7: num += (ch[off++] - '0') * 1000000; case 6: num += (ch[off++] - '0') * 100000; case 5: num += (ch[off++] - '0') * 10000; case 4: num += (ch[off++] - '0') * 1000; case 3: num += (ch[off++] - '0') * 100; case 2: num += (ch[off] - '0') * 10; } return num; }
Helper method to (more) efficiently parse integer numbers from String values.
/** * Helper method to (more) efficiently parse integer numbers from * String values. */
public static int parseInt(String s) { /* Ok: let's keep strategy simple: ignoring optional minus sign, * we'll accept 1 - 9 digits and parse things efficiently; * otherwise just defer to JDK parse functionality. */ char c = s.charAt(0); int len = s.length(); boolean neg = (c == '-'); int offset = 1; // must have 1 - 9 digits after optional sign: // negative? if (neg) { if (len == 1 || len > 10) { return Integer.parseInt(s); } c = s.charAt(offset++); } else { if (len > 9) { return Integer.parseInt(s); } } if (c > '9' || c < '0') { return Integer.parseInt(s); } int num = c - '0'; if (offset < len) { c = s.charAt(offset++); if (c > '9' || c < '0') { return Integer.parseInt(s); } num = (num * 10) + (c - '0'); if (offset < len) { c = s.charAt(offset++); if (c > '9' || c < '0') { return Integer.parseInt(s); } num = (num * 10) + (c - '0'); // Let's just loop if we have more than 3 digits: if (offset < len) { do { c = s.charAt(offset++); if (c > '9' || c < '0') { return Integer.parseInt(s); } num = (num * 10) + (c - '0'); } while (offset < len); } } } return neg ? -num : num; } public static long parseLong(char[] ch, int off, int len) { // Note: caller must ensure length is [10, 18] int len1 = len-9; long val = parseInt(ch, off, len1) * L_BILLION; return val + (long) parseInt(ch, off+len1, 9); } public static long parseLong(String s) { /* Ok, now; as the very first thing, let's just optimize case of "fake longs"; * that is, if we know they must be ints, call int parsing */ int length = s.length(); if (length <= 9) { return (long) parseInt(s); } // !!! TODO: implement efficient 2-int parsing... return Long.parseLong(s); }
Helper method for determining if given String representation of an integral number would fit in 64-bit Java long or not. Note that input String must NOT contain leading minus sign (even if 'negative' is set to true).
Params:
  • negative – Whether original number had a minus sign (which is NOT passed to this method) or not
/** * Helper method for determining if given String representation of * an integral number would fit in 64-bit Java long or not. * Note that input String must NOT contain leading minus sign (even * if 'negative' is set to true). * * @param negative Whether original number had a minus sign (which is * NOT passed to this method) or not */
public static boolean inLongRange(char[] ch, int off, int len, boolean negative) { String cmpStr = negative ? MIN_LONG_STR_NO_SIGN : MAX_LONG_STR; int cmpLen = cmpStr.length(); if (len < cmpLen) return true; if (len > cmpLen) return false; for (int i = 0; i < cmpLen; ++i) { int diff = ch[off+i] - cmpStr.charAt(i); if (diff != 0) { return (diff < 0); } } return true; }
Similar to inLongRange(char[], int, int, boolean), but with String argument
Params:
  • negative – Whether original number had a minus sign (which is NOT passed to this method) or not
/** * Similar to {@link #inLongRange(char[],int,int,boolean)}, but * with String argument * * @param negative Whether original number had a minus sign (which is * NOT passed to this method) or not */
public static boolean inLongRange(String s, boolean negative) { String cmp = negative ? MIN_LONG_STR_NO_SIGN : MAX_LONG_STR; int cmpLen = cmp.length(); int alen = s.length(); if (alen < cmpLen) return true; if (alen > cmpLen) return false; // could perhaps just use String.compareTo()? for (int i = 0; i < cmpLen; ++i) { int diff = s.charAt(i) - cmp.charAt(i); if (diff != 0) { return (diff < 0); } } return true; } public static int parseAsInt(String s, int def) { if (s == null) { return def; } s = s.trim(); int len = s.length(); if (len == 0) { return def; } // One more thing: use integer parsing for 'simple' int i = 0; if (i < len) { // skip leading sign: char c = s.charAt(0); if (c == '+') { // for plus, actually physically remove s = s.substring(1); len = s.length(); } else if (c == '-') { // minus, just skip for checks, must retain ++i; } } for (; i < len; ++i) { char c = s.charAt(i); // if other symbols, parse as Double, coerce if (c > '9' || c < '0') { try { return (int) parseDouble(s); } catch (NumberFormatException e) { return def; } } } try { return Integer.parseInt(s); } catch (NumberFormatException e) { } return def; } public static long parseAsLong(String s, long def) { if (s == null) { return def; } s = s.trim(); int len = s.length(); if (len == 0) { return def; } // One more thing: use long parsing for 'simple' int i = 0; if (i < len) { // skip leading sign: char c = s.charAt(0); if (c == '+') { // for plus, actually physically remove s = s.substring(1); len = s.length(); } else if (c == '-') { // minus, just skip for checks, must retain ++i; } } for (; i < len; ++i) { char c = s.charAt(i); // if other symbols, parse as Double, coerce if (c > '9' || c < '0') { try { return (long) parseDouble(s); } catch (NumberFormatException e) { return def; } } } try { return Long.parseLong(s); } catch (NumberFormatException e) { } return def; } public static double parseAsDouble(String s, double def) { if (s == null) { return def; } s = s.trim(); int len = s.length(); if (len == 0) { return def; } try { return parseDouble(s); } catch (NumberFormatException e) { } return def; } public static double parseDouble(String s) throws NumberFormatException { // [JACKSON-486]: avoid some nasty float representations... but should it be MIN_NORMAL or MIN_VALUE? /* as per [JACKSON-827], let's use MIN_VALUE as it is available on all JDKs; normalized * only in JDK 1.6. In practice, should not really matter. */ if (NASTY_SMALL_DOUBLE.equals(s)) { return Double.MIN_VALUE; } return Double.parseDouble(s); } public static BigDecimal parseBigDecimal(String s) throws NumberFormatException { try { return new BigDecimal(s); } catch (NumberFormatException e) { throw _badBD(s); } } public static BigDecimal parseBigDecimal(char[] b) throws NumberFormatException { return parseBigDecimal(b, 0, b.length); } public static BigDecimal parseBigDecimal(char[] b, int off, int len) throws NumberFormatException { try { return new BigDecimal(b, off, len); } catch (NumberFormatException e) { throw _badBD(new String(b, off, len)); } } private static NumberFormatException _badBD(String s) { return new NumberFormatException("Value \""+s+"\" can not be represented as BigDecimal"); } }