package com.fasterxml.jackson.core.io;
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).
*/
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 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 final static int parseInt(char[] digitChars, int offset, int len)
{
int num = digitChars[offset] - '0';
len += offset;
// This looks ugly, but appears the fastest way (as per measurements)
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
if (++offset < len) {
num = (num * 10) + (digitChars[offset] - '0');
}
}
}
}
}
}
}
}
return num;
}
/**
* Helper method to (more) efficiently parse integer numbers from
* String values.
*/
public final static int parseInt(String str)
{
/* 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 = str.charAt(0);
int length = str.length();
boolean negative = (c == '-');
int offset = 1;
// must have 1 - 9 digits after optional sign:
// negative?
if (negative) {
if (length == 1 || length > 10) {
return Integer.parseInt(str);
}
c = str.charAt(offset++);
} else {
if (length > 9) {
return Integer.parseInt(str);
}
}
if (c > '9' || c < '0') {
return Integer.parseInt(str);
}
int num = c - '0';
if (offset < length) {
c = str.charAt(offset++);
if (c > '9' || c < '0') {
return Integer.parseInt(str);
}
num = (num * 10) + (c - '0');
if (offset < length) {
c = str.charAt(offset++);
if (c > '9' || c < '0') {
return Integer.parseInt(str);
}
num = (num * 10) + (c - '0');
// Let's just loop if we have more than 3 digits:
if (offset < length) {
do {
c = str.charAt(offset++);
if (c > '9' || c < '0') {
return Integer.parseInt(str);
}
num = (num * 10) + (c - '0');
} while (offset < length);
}
}
}
return negative ? -num : num;
}
public final static long parseLong(char[] digitChars, int offset, int len)
{
// Note: caller must ensure length is [10, 18]
int len1 = len-9;
long val = parseInt(digitChars, offset, len1) * L_BILLION;
return val + (long) parseInt(digitChars, offset+len1, 9);
}
public final static long parseLong(String str)
{
/* 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 = str.length();
if (length <= 9) {
return (long) parseInt(str);
}
// !!! TODO: implement efficient 2-int parsing...
return Long.parseLong(str);
}
/**
* 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 final static boolean inLongRange(char[] digitChars, int offset, 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 = digitChars[offset+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 negative Whether original number had a minus sign (which is
* NOT passed to this method) or not
*/
public final static boolean inLongRange(String numberStr, boolean negative)
{
String cmpStr = negative ? MIN_LONG_STR_NO_SIGN : MAX_LONG_STR;
int cmpLen = cmpStr.length();
int actualLen = numberStr.length();
if (actualLen < cmpLen) return true;
if (actualLen > cmpLen) return false;
// could perhaps just use String.compareTo()?
for (int i = 0; i < cmpLen; ++i) {
int diff = numberStr.charAt(i) - cmpStr.charAt(i);
if (diff != 0) {
return (diff < 0);
}
}
return true;
}
public static int parseAsInt(String input, int defaultValue)
{
if (input == null) {
return defaultValue;
}
input = input.trim();
int len = input.length();
if (len == 0) {
return defaultValue;
}
// One more thing: use integer parsing for 'simple'
int i = 0;
if (i < len) { // skip leading sign:
char c = input.charAt(0);
if (c == '+') { // for plus, actually physically remove
input = input.substring(1);
len = input.length();
} else if (c == '-') { // minus, just skip for checks, must retain
++i;
}
}
for (; i < len; ++i) {
char c = input.charAt(i);
// if other symbols, parse as Double, coerce
if (c > '9' || c < '0') {
try {
return (int) parseDouble(input);
} catch (NumberFormatException e) {
return defaultValue;
}
}
}
try {
return Integer.parseInt(input);
} catch (NumberFormatException e) { }
return defaultValue;
}
public static long parseAsLong(String input, long defaultValue)
{
if (input == null) {
return defaultValue;
}
input = input.trim();
int len = input.length();
if (len == 0) {
return defaultValue;
}
// One more thing: use long parsing for 'simple'
int i = 0;
if (i < len) { // skip leading sign:
char c = input.charAt(0);
if (c == '+') { // for plus, actually physically remove
input = input.substring(1);
len = input.length();
} else if (c == '-') { // minus, just skip for checks, must retain
++i;
}
}
for (; i < len; ++i) {
char c = input.charAt(i);
// if other symbols, parse as Double, coerce
if (c > '9' || c < '0') {
try {
return (long) parseDouble(input);
} catch (NumberFormatException e) {
return defaultValue;
}
}
}
try {
return Long.parseLong(input);
} catch (NumberFormatException e) { }
return defaultValue;
}
public static double parseAsDouble(String input, double defaultValue)
{
if (input == null) {
return defaultValue;
}
input = input.trim();
int len = input.length();
if (len == 0) {
return defaultValue;
}
try {
return parseDouble(input);
} catch (NumberFormatException e) { }
return defaultValue;
}
public final static double parseDouble(String numStr) 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(numStr)) {
return Double.MIN_VALUE;
}
return Double.parseDouble(numStr);
}
}