Issue while casting amount to Double

Question

my program is receiving amount value as string and then converting it to Double using Double.parseDouble(transAmt).

Now we are getting issue when amount passed is "100.00" .

Please advise if while casting to double zero precision digits will be lost

Can you post an isolated example of your problem? It will be easier for people to help. — Gunner Stone, Dec 06 '17 at 07:47
There is literally no information to process in this question. — SPlatten, Dec 06 '17 at 07:49
Possible duplicate of [Convert String to double in Java](https://stackoverflow.com/questions/5769669/convert-string-to-double-in-java) — vinS, Dec 06 '17 at 07:50

Henry · Answer 1 · 2017-12-06T08:14:31.373

1

With some guessing what the "issue" might be: double in Java is an approximation of the mathematical real numbers. As such there is no difference between 100 and 100.00 it is just the same value.

edited Dec 06 '17 at 08:14

answered Dec 06 '17 at 08:05

Henry

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score 0 · Answer 2 · answered Dec 06 '17 at 08:14

double holds no precision, and is an approximation, a sum of (negative) powers of 2. Hence 3.10 might on output be 3.0999999785, an error which enlarges when summing or multiplying.

For holding a precision and being precise - as with financial software - BigDecimal is used.

BigDecimal amount = new BigDecimal("12.99"); // A precision of 2 digits.
BigDecimal base = new BigDecimal("4.33");
assert base.multiply(BigDecimal.valueOf(3)).compareTo(amount) == 0;

Unfortunately with BigDecimal normal math operators are not available, but in general it is not as unsafe as with double.

Issue while casting amount to Double

2 Answers2