Java SHA1 sha1(File file)

Description

Returns the SHA1 hash of a File

License

Open Source License

Declaration

public static String sha1(File file) throws IOException 

Method Source Code

//package com.java2s;
/*************************************************************************************
 * Copyright (c) 2015 Red Hat, Inc. and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:/*  w  w  w .j  ava 2s.  c o m*/
 *       JBoss by Red Hat - Initial implementation.
 ************************************************************************************/

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Main {
    /**
     * Returns the SHA1 hash of a {@link File}
     */
    public static String sha1(File file) throws IOException {
        if (file == null) {
            return null;
        }
        return sha1(file.toPath());
    }

    /**
     * Returns the SHA1 hash of a file referenced by a {@link Path}
     */
    public static String sha1(Path pathToFile) throws IOException {
        if (pathToFile != null) {
            try (InputStream input = Files.newInputStream(pathToFile)) {
                return sha1(input);
            }
        }
        return null;

    }

    /**
     * Returns the SHA1 hash of a {@link String}
     */
    public static String sha1(String text) throws IOException {
        if (text == null) {
            return null;
        }
        return sha1(new ByteArrayInputStream(text.getBytes(StandardCharsets.UTF_8)));
    }

    /**
     * Returns the SHA1 hash of an {@link InputStream}.
     */
    public static String sha1(InputStream input) throws IOException {
        if (input == null) {
            return null;
        }
        StringBuilder sb = new StringBuilder();
        try {
            MessageDigest md = MessageDigest.getInstance("SHA1");
            byte[] bytes = new byte[16 * 1024];
            int count = 0;
            while ((count = input.read(bytes)) != -1) {
                md.update(bytes, 0, count);
            }
            byte[] digestBytes = md.digest();
            for (int i = 0; i < digestBytes.length; i++) {
                sb.append(Integer.toString((digestBytes[i] & 0xff) + 0x100, 16).substring(1));
            }
        } catch (NoSuchAlgorithmException cantHappen) {
        }
        return sb.toString();
    }
}

Related

1. sha1(byte[] message)
2. SHA1(byte[] src)
3. SHA1(ByteBuffer buf, int offset, int size)
4. sha1(File f)
5. sha1(File file)
6. sha1(File sourceFile)
7. sha1(final byte[] bytes)
8. sha1(final File file)
9. sha1(final String data)