Calculates a SHA1 digest for a string. - Java Security

Java examples for Security:SHA

  1. HOME
  2. Java
  3. Security
  4. SHA

Description

Calculates a SHA1 digest for a string.

Demo Code

/*//  w  ww  . j a  va 2 s. co  m
 * Sonatype Nexus (TM) Open Source Version
 * Copyright (c) 2007-2014 Sonatype, Inc.
 * All rights reserved. Includes the third-party code listed at http://links.sonatype.com/products/nexus/oss/attributions.
 *
 * This program and the accompanying materials are made available under the terms of the Eclipse Public License Version 1.0,
 * which accompanies this distribution and is available at http://www.eclipse.org/legal/epl-v10.html.
 *
 * Sonatype Nexus (TM) Professional Version is available from Sonatype, Inc. "Sonatype" and "Sonatype Nexus" are trademarks
 * of Sonatype, Inc. Apache Maven is a trademark of the Apache Software Foundation. M2eclipse is a trademark of the
 * Eclipse Foundation. All other trademarks are the property of their respective owners.
 */
//package com.java2s;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Main {
    public static final String SHA1_ALG = "SHA1";
    public static final Charset UTF8_CHARSET = Charset.forName("UTF-8");

    public static byte[] getSha1Digest(final byte[] byteArray) {
        try {
            return getDigest(SHA1_ALG, new ByteArrayInputStream(byteArray));
        } catch (NoSuchAlgorithmException e) {
            // will not happen
            return null;
        } catch (IOException e) {
            // will not happen
            return null;
        }
    }

    /**
     * Calculates a SHA1 digest for a string.
     */
    public static byte[] getSha1Digest(final String content) {
        try {
            return getDigest(
                    SHA1_ALG,
                    new ByteArrayInputStream(content.getBytes(UTF8_CHARSET)));
        } catch (NoSuchAlgorithmException e) {
            // will not happen
            return null;
        } catch (IOException e) {
            // will not happen
            return null;
        }
    }

    /**
     * Calculates a SHA1 digest for a stream.
     */
    public static byte[] getSha1Digest(final InputStream is)
            throws IOException {
        try {
            return getDigest(SHA1_ALG, is);
        } catch (NoSuchAlgorithmException e) {
            // will not happen
            return null;
        }
    }

    /**
     * Calculates a SHA1 digest for a file.
     */
    public static byte[] getSha1Digest(final File file) throws IOException {
        FileInputStream fis = null;
        try {
            fis = new FileInputStream(file);
            return getDigest(SHA1_ALG, fis);
        } catch (NoSuchAlgorithmException e) {
            return null;
        } finally {
            close(fis);
        }
    }

    /**
     * Calculates a digest for a String user the requested algorithm.
     */
    public static byte[] getDigest(final String alg, final InputStream is)
            throws NoSuchAlgorithmException, IOException {
        byte[] result = null;
        try {
            final byte[] buffer = new byte[1024];
            final MessageDigest md = MessageDigest.getInstance(alg);
            int numRead;
            do {
                numRead = is.read(buffer);
                if (numRead > 0) {
                    md.update(buffer, 0, numRead);
                }
            } while (numRead != -1);
            result = md.digest();
        } finally {
            close(is);
        }
        return result;
    }

    public static void close(final InputStream inputStream) {
        if (inputStream == null) {
            return;
        }
        try {
            inputStream.close();
        } catch (IOException ex) {
            // ignore
        }
    }
}

Related Tutorials