CONVERT STRING TO LONG ERROR CODE
CONVERT STRING TO LONG ERROR PLUS

Hexadecimally, this negative number is represented as the positive value 'cafebabe', which in turn cannot be converted back by the parseInt() method. We see that hex contains the negative value -889,275,714 (I've inserted the thousands separators here for the sake of clarity).

CONVERT STRING TO LONG ERROR CODE

( 'i = ' + i) Code language: Java ( java ) ( 'hex binary = ' + Integer.toBinaryString(hex)) Let's add some debug output to the code above: int hex = 0xCAFEBABE If it is 1, the number is negative (for details on negative numbers, see this Wikipedia article). In an int – which is always signed in Java – the first bit stands for the sign. Then why can we assign the number to the int variable hex? The binary representation of the numbers plays an (intended) trick on us. This number is higher than Integer.MAX_INT and therefore, cannot be represented as an int. If you convert 'cafebabe' to the decimal system, you get 3,405,691,582. The reason is that the parseInt() method assumes the given number to be positive unless a minus sign precedes it. Why can't this String be converted back to an int? This attempt results in the following error: Exception in thread 'main' : For input string: 'cafebabe'įirst of all: The String s contains 'cafebabe' as expected. Int i = Integer.parseInt(s, 16) Code language: Java ( java ) It becomes interesting (not to say: confusing) if, for example, we convert the valid int value 0xCAFEBABE into a hex String and then back into an int: int hex = 0xCAFEBABE In all the above cases, the number to be parsed must be within the range Integer.MIN_VALUE (= -2 31 = -2,147,483,648) to Integer.MAX_VALUE (= 2 31-1 = 2,147,483,647). A hexadecimal number can be parsed as follows: The parameter radix specifies the base of the number system. Integer i = Integer.valueOf(s, radix) (→ JavaDoc).int i = Integer.parseInt(s, radix) (→ JavaDoc).To parse other number systems, the following overloaded methods are available: Integer.parseInt('1,000') // Thousands separator not allowed.Integer.parseInt('3.14') // Decimal point not allowed.Integer.parseInt(' 1') // Space not allowed.Integer.parseInt('') // Empty string not allowed.The following Strings are not allowed and result in NumberFormatExceptions:

CONVERT STRING TO LONG ERROR PLUS

The String to convert must contain only digits, optionally with a plus or minus sign in front.

The second method internally calls the first method and converts the result to an Integer object.

Integer i = Integer.valueOf(s) (→ JavaDoc).

int i = Integer.parseInt(s) (→ JavaDoc).Let's first look at the options to parse a String into an int (or Integer). You can find the source code for this article in my GitHub repository. Today you will learn what to consider in the opposite direction, i.e., when parsing a String to an int. In the previous article, I showed you that '' + i is the fastest way to convert an int into a String in Java.

Convert string to long error