http://commons.apache.org/proper/commons-crypto/: Apache Commons Crypto is a cryptographic library optimized with AES-NI (Advanced Encryption Standard New Instructions). It provides Java API for both cipher level and Java stream level. Developers can use it to implement high performance AES encryption/decryption with the minimum code and effort. Please note that Crypto doesn't implement the cryptographic algorithm such as AES directly. It wraps to Openssl or JCE which implement the algorithms. Features -------- 1. Cipher API for low level cryptographic operations. 2. Java stream API (CryptoInputStream/CryptoOutputStream) for high level stream encyrption/decryption. 3. Both optimized with high performance AES encryption/decryption. (1400 MB/s - 1700 MB/s throughput in modern Xeon processors). 4. JNI-based implementation to achieve comparable performance to the native C++ version based on OpenSsl. 5. Portable across various operating systems (currently only Linux/MacOSX/Windows); Apache Commons Crypto loads the library according to your machine environment (it checks system properties, `os.name` and `os.arch`). 6. Simple usage. Add the commons-crypto-(version).jar file to your classpath. Export restrictions ------------------- This distribution includes cryptographic software. The country in which you currently reside may have restrictions on the import, possession, use, and/or re-export to another country, of encryption software. BEFORE using any encryption software, please check your country's laws, regulations and policies concerning the import, possession, or use, and re-export of encryption software, to see if this is permitted. See <http://www.wassenaar.org/> for more information. The U.S. Government Department of Commerce, Bureau of Industry and Security (BIS), has classified this software as Export Commodity Control Number (ECCN) 5D002.C.1, which includes information security software using or performing cryptographic functions with asymmetric algorithms. The form and manner of this Apache Software Foundation distribution makes it eligible for export under the License Exception ENC Technology Software Unrestricted (TSU) exception (see the BIS Export Administration Regulations, Section 740.13) for both object code and source code. The following provides more details on the included cryptographic software: * Commons Crypto use [Java Cryptography Extension](http://docs.oracle.com/javase/8/docs/technotes/guides/security/crypto/CryptoSpec.html) provided by Java * Commons Crypto link to and use [OpenSSL](https://www.openssl.org/) ciphers (The Apache Software Foundation)
  • Colin Ma
  • Xianda Ke
  • Ke Jia
  • George Kankava
  • Aaron T Myers
  • Andrew Wang
  • Chris Nauroth
  • Colin P. McCabe
  • Dapeng Sun
  • Dian Fu
  • Dong Chen
  • Ferdinand Xu
  • Haifeng Chen
  • Marcelo Vanzin
  • Uma Maheswara Rao G
  • Yi Liu 
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.crypto.utils;

import java.io.IOException;
import java.io.InputStream;

import org.apache.commons.crypto.stream.input.Input;


General utility methods for working with IO.

/**
 * General utility methods for working with IO.
 */
public final class IoUtils {

    
The private constructor of IoUtils. 
/**
     * The private constructor of {@link IoUtils}.
     */
    private IoUtils() {
    }

    
Does the readFully based on the Input read.

Params:
  • in – the input stream of bytes.
  • buf – the buffer to be read.
  • off – the start offset in array buffer.
  • len – the maximum number of bytes to read.
Throws:
/**
     * Does the readFully based on the Input read.
     *
     * @param in the input stream of bytes.
     * @param buf the buffer to be read.
     * @param off the start offset in array buffer.
     * @param len the maximum number of bytes to read.
     * @throws IOException if an I/O error occurs.
     */
    public static void readFully(InputStream in, byte buf[], int off, int len)
            throws IOException {
        int toRead = len;
        while (toRead > 0) {
            int ret = in.read(buf, off, toRead);
            if (ret < 0) {
                throw new IOException("Premature EOF from inputStream");
            }
            toRead -= ret;
            off += ret;
        }
    }

    
Does the readFully based on Input's positioned read. This does not change
the current offset of the stream and is thread-safe.

Params:
  • in – the input source.
  • position – the given position.
  • buffer – the buffer to be read.
  • length – the maximum number of bytes to read.
  • offset – the start offset in array buffer.
Throws:
/**
     * Does the readFully based on Input's positioned read. This does not change
     * the current offset of the stream and is thread-safe.
     *
     * @param in the input source.
     * @param position the given position.
     * @param buffer the buffer to be read.
     * @param length the maximum number of bytes to read.
     * @param offset the start offset in array buffer.
     * @throws IOException if an I/O error occurs.
     */
    public static void readFully(Input in, long position, byte[] buffer,
            int offset, int length) throws IOException {
        int nread = 0;
        while (nread < length) {
            int nbytes = in.read(position + nread, buffer, offset + nread,
                    length - nread);
            if (nbytes < 0) {
                throw new IOException(
                        "End of stream reached before reading fully.");
            }
            nread += nbytes;
        }
    }

    
Closes the Closeable objects and ignore any IOException or null pointers. Must only be used for cleanup in exception handlers. 
Params:
  • closeables – the objects to close.
/**
     * Closes the Closeable objects and <b>ignore</b> any {@link IOException} or
     * null pointers. Must only be used for cleanup in exception handlers.
     *
     * @param closeables the objects to close.
     */
    public static void cleanup(java.io.Closeable... closeables) {
        for (java.io.Closeable c : closeables) {
            if (c != null) {
                try {
                    c.close();
                } catch (IOException e) { // NOPMD
                }
            }
        }
    }
}