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package com.fasterxml.jackson.core.io;

import com.fasterxml.jackson.core.io.doubleparser.FastDoubleParser;
import com.fasterxml.jackson.core.io.doubleparser.FastFloatParser;

import java.math.BigDecimal;
import java.math.BigInteger;

public final class NumberInput
{
    // numbers with more than these characters are better parsed with BigDecimalParser
    // parsing numbers with many digits in Java is slower than O(n)
    private final static int LARGE_INT_SIZE = 1250;

    /**
     * Formerly used constant for a value that was problematic on certain
     * pre-1.8 JDKs.
     *
     * @deprecated Since 2.14 -- do not use
     */
    @Deprecated // since 2.14
    public final static String NASTY_SMALL_DOUBLE = "2.2250738585072012e-308";

    /**
     * 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 unsigned integers that are known to fit into
     * regular 32-bit signed int type. This means that length is
     * between 1 and 9 digits (inclusive) and there is no sign character.
     *

* Note: public to let unit tests call it; not meant to be used by any * code outside this package. * * @param ch Buffer that contains integer value to decode * @param off Offset of the first digit character in buffer * @param len Length of the number to decode (in characters) * * @return Decoded {@code int} value */ public static int parseInt(char[] ch, int off, int len) { if (len > 0 && ch[off] == '+') { off++; 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. Input String must be simple Java integer value. * No range checks are made to verify that the value fits in 32-bit Java {@code int}: * caller is expected to only calls this in cases where this can be guaranteed * (basically: number of digits does not exceed 9) *

* NOTE: semantics differ significantly from {@link #parseInt(char[], int, int)}. * * @param s String that contains integer value to decode * * @return Decoded {@code int} value */ 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); } /** * Similar to {@link #parseInt(String)} but for {@code long} values. * * @param s String that contains {@code long} value to decode * * @return Decoded {@code long} value */ 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). * * @param ch Buffer that contains long value to check * @param off Offset of the first digit character in buffer * @param len Length of the number to decode (in characters) * @param negative Whether original number had a minus sign (which is * NOT passed to this method) or not * * @return {@code True} if specified String representation is within Java * {@code long} range; {@code false} if 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 {@link #inLongRange(char[],int,int,boolean)}, but * with String argument * * @param s String that contains {@code long} value to check * @param negative Whether original number had a minus sign (which is * NOT passed to this method) or not * * @return {@code True} if specified String representation is within Java * {@code long} range; {@code false} if 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; // skip leading sign, if any final char sign = s.charAt(0); if (sign == '+') { // for plus, actually physically remove s = s.substring(1); len = s.length(); } else if (sign == '-') { // minus, just skip for checks, must retain i = 1; } for (; i < len; ++i) { char c = s.charAt(i); // if other symbols, parse as Double, coerce if (c > '9' || c < '0') { try { //useFastParser=true is used because there is a lot less risk that small changes in result will have an affect //and performance benefit is useful return (int) parseDouble(s, true); } 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; // skip leading sign, if any final char sign = s.charAt(0); if (sign == '+') { // for plus, actually physically remove s = s.substring(1); len = s.length(); } else if (sign == '-') { // minus, just skip for checks, must retain i = 1; } for (; i < len; ++i) { char c = s.charAt(i); // if other symbols, parse as Double, coerce if (c > '9' || c < '0') { try { //useFastParser=true is used because there is a lot less risk that small changes in result will have an affect //and performance benefit is useful return (long) parseDouble(s, true); } catch (NumberFormatException e) { return def; } } } try { return Long.parseLong(s); } catch (NumberFormatException e) { } return def; } /** * @param s a string representing a number to parse * @param def the default to return if `s` is not a parseable number * @return closest matching double (or `def` if there is an issue with `s`) where useFastParser=false * @see #parseAsDouble(String, double, boolean) */ public static double parseAsDouble(final String s, final double def) { return parseAsDouble(s, def, false); } /** * @param s a string representing a number to parse * @param def the default to return if `s` is not a parseable number * @param useFastParser whether to use {@link com.fasterxml.jackson.core.io.doubleparser} * @return closest matching double (or `def` if there is an issue with `s`) * @since 2.14 */ public static double parseAsDouble(String s, final double def, final boolean useFastParser) { if (s == null) { return def; } s = s.trim(); int len = s.length(); if (len == 0) { return def; } try { return parseDouble(s, useFastParser); } catch (NumberFormatException e) { } return def; } /** * @param s a string representing a number to parse * @return closest matching double * @throws NumberFormatException if string cannot be represented by a double where useFastParser=false * @see #parseDouble(String, boolean) */ public static double parseDouble(final String s) throws NumberFormatException { return parseDouble(s, false); } /** * @param s a string representing a number to parse * @param useFastParser whether to use {@link com.fasterxml.jackson.core.io.doubleparser} * @return closest matching double * @throws NumberFormatException if string cannot be represented by a double * @since v2.14 */ public static double parseDouble(final String s, final boolean useFastParser) throws NumberFormatException { return useFastParser ? FastDoubleParser.parseDouble(s) : Double.parseDouble(s); } /** * @param s a string representing a number to parse * @return closest matching float * @throws NumberFormatException if string cannot be represented by a float where useFastParser=false * @see #parseFloat(String, boolean) * @since v2.14 */ public static float parseFloat(final String s) throws NumberFormatException { return parseFloat(s, false); } /** * @param s a string representing a number to parse * @param useFastParser whether to use {@link com.fasterxml.jackson.core.io.doubleparser} * @return closest matching float * @throws NumberFormatException if string cannot be represented by a float * @since v2.14 */ public static float parseFloat(final String s, final boolean useFastParser) throws NumberFormatException { return useFastParser ? FastFloatParser.parseFloat(s) : Float.parseFloat(s); } public static BigDecimal parseBigDecimal(String s) throws NumberFormatException { return BigDecimalParser.parse(s); } public static BigDecimal parseBigDecimal(char[] ch, int off, int len) throws NumberFormatException { return BigDecimalParser.parse(ch, off, len); } public static BigDecimal parseBigDecimal(char[] ch) throws NumberFormatException { return BigDecimalParser.parse(ch); } /** * @param s a string representing a number to parse * @return a BigInteger * @throws NumberFormatException if string cannot be represented by a BigInteger * @since v2.14 */ public static BigInteger parseBigInteger(String s) throws NumberFormatException { if (s.length() > LARGE_INT_SIZE) { return BigDecimalParser.parse(s).toBigInteger(); } return new BigInteger(s); } }





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