I have a GUI desktop application which generates different types of hash (example MD5) for files and directories. Recently, when I was testing with a 1GB test file I recognized that it becomes slower and slower over time. At the first hashing, it takes about 2 seconds for a 1GB file, however later, for the ex…
Tag: hash
how to decrypt using DatatypeConverter MD5 In JAVA?
Answer You can’t. That’s what hashing is about. This is not a API or library limitation but a mathematical one, which is there by design. You need to understand that hashing and encryption/ decryption are two completely different things (which are often used together). Hashing A hash, or to be pre…
Does this hashCode make sense?
I came across some an hashcode function that does kind of the following: I am not fully convinced of the method used to calculate the hashCode, I know use of prime numbers yields a better distribution in general. But in this implementation I am not really convinced that’s the case. For example assuming …
Chained Hashing Program; the method is undefined for the type error
I have made multiple methods, and they all have the error called and there is another problem that is Why are the methods undefined? Is there something wrong with the class? Or is there something wrong in someplace I am ignorant about. adding code and the class with methods underneath. code ChainHashEx : clas…
HashMap: Is there a way to search by hashcode and not by key?
I may sound completely wrong but: I’ve read as many posts as I could find here about HashMap and hashcode . I did not get what I was looking for exactly. I am going to try to be as precise as I can. Let’s say I have a huge hashmap where : keys are of type my_struct and values as
Hasmap merge function value inside an object
I am trying to get a quantity count of products from a list of sales. So what I have is: The current way I have done it is based on this answer of integers: how to merge more than one hashmaps also sum the values of same key in java So, right now im traversing a list of sale objects,
What is the equivalent of hashing Java code into C#?
I have a strange problem in getting equivalent hash code from C# code translated into Java. I don’t know, what MessageDigest update method do. It should only update the contents of digest and should compute hash after calling digest. Same thing I am doing in C# with SHAManaged512.ComputeHash(content). B…
SHA-512 hashing with Android
I was wondering if I can SHA-512 hash a string on Android Studio without a salt. I’ve seen other questions, but they all involve the salt, but I want something like this: And TextBox will read c1527cd893c124773d811911970c8fe6e857d6df5dc9226bd8a160614c0cd963a4ddea2b94bb7d36021ef9d865d5cea294a82dd49a0bb26…
How to make “MessageDigest SHA-1 and Signature NONEwithRSA” equivalent to “Signature SHA1withRSA “
I am interested in applying a SHA-1 hash with RSA signature to some data, but I need to do it in two steps – apply hash first and then sign the data. The Signature.sign() function appears to create a more complex (ASN.1?) data structure that is ultimately signed (see this question). How can I make the t…
How to create a HashMap with two keys (Key-Pair, Value)?
I have a 2D array of Integers. I want them to be put into a HashMap. But I want to access the elements from the HashMap based on Array Index. Something like: For A[2][5], map.get(2,5) which returns a value associated with that key. But how do I create a hashMap with a pair of keys? Or in general, multiple key…