net.dankito.utils.hashing.HashService.kt Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of java-utils Show documentation

Some basic utils needed in many projects

The newest version!

package net.dankito.utils.hashing


import net.dankito.utils.extensions.toHexString
import net.dankito.utils.io.FileUtils
import java.io.File
import java.io.FileNotFoundException
import java.io.IOException
import java.nio.charset.Charset
import java.security.MessageDigest
import java.security.NoSuchAlgorithmException


open class HashService(protected val fileUtils: FileUtils = FileUtils()) {

    companion object {
        val DefaultDigestCharset: Charset = Charset.forName("UTF-8")
    }


    @Throws(NoSuchAlgorithmException::class)
    open fun hashString(hashAlgorithm: HashAlgorithm, stringToHash: String,
                        charset: Charset = DefaultDigestCharset): String {

        return convertBytesToHexString(hashStringToBytes(hashAlgorithm, stringToHash))
    }

    @Throws(NoSuchAlgorithmException::class)
    open fun hashStringToBytes(hashAlgorithm: HashAlgorithm, stringToHash: String,
                               charset: Charset = DefaultDigestCharset): ByteArray {

        val messageDigest = MessageDigest.getInstance(hashAlgorithm.algorithmName)
        val stringToHashBytes = stringToHash.toByteArray(charset)

        messageDigest.update(stringToHashBytes)

        return messageDigest.digest()
    }

    @Throws(NoSuchAlgorithmException::class, IOException::class, FileNotFoundException::class)
    open fun getFileHash(hashAlgorithm: HashAlgorithm, file: File): String {
        val messageDigest = MessageDigest.getInstance(hashAlgorithm.algorithmName)

        fileUtils.forEachBlock(file) { buffer, _ ->
            messageDigest.update(buffer)
        }

        val digestBytes = messageDigest.digest()

        return convertBytesToHexString(digestBytes)

    }

    protected open fun convertBytesToHexString(digestBytes: ByteArray): String {
        return digestBytes.toHexString()
    }

}