Java Digest digest(final InputStream inputStream, final MessageDigest digester)

Description

digest

License

LGPL

Declaration

public static InputStream digest(final InputStream inputStream, final MessageDigest digester) 

Method Source Code

//package com.java2s;
//License from project: LGPL 

import java.io.IOException;
import java.io.InputStream;
import java.security.*;

public class Main {
    public static InputStream digest(final InputStream inputStream, final MessageDigest digester) {
        return new DigestInputStream(removeOSSpecificChars(inputStream), digester);
    }//ww  w.ja  va  2  s. co m

    private static InputStream removeOSSpecificChars(final InputStream inputStream) {
        return new InputStream() {
            @Override
            public int read() throws IOException {
                do {
                    final byte next = (byte) inputStream.read();
                    if (!isOsSpecificChar(next)) {
                        return next;
                    }
                } while (true);
            }
        };
    }

    /**
     * EBICS Specification 14 Appendix: Signature process for the electronic signature:
     * <p></p>
     * <p>The characters restricted to the operating system (CR, LF and Ctrl-Z) are not included in the calculation
     * of hash values of the A005/A006 ES (analogous to A004 ES).</p>
     *
     * @param octet the byte
     * @return <code>true</code> if the octet reflects an OS specific character
     */
    static boolean isOsSpecificChar(final byte octet) {
        switch (octet) {
        case '\r': // CR
        case '\n': // LF
        case 0x1A: // CTRL-Z / EOF
            return true;

        default:
            return false;
        }
    }
}

Related

1. digest(byte[] input, final String algorithm)
2. digest(byte[] input, String algorithm, byte[] salt, int iterations)
3. digest(byte[] message, String hash_alg)
4. digest(final @Nullable String[] tokens, @Nullable final Date[] dates)
5. digest(final byte[] data)
6. digest(final java.security.MessageDigest messageDigest, final java.nio.ByteBuffer data)
7. digest(final String algorithm, final byte[] bytes)
8. digest(final String password)
9. digest(InputStream input, String algorithm)