All Downloads are FREE. Search and download functionalities are using the official Maven repository.

io.undertow.util.FlexBase64 Maven / Gradle / Ivy

There is a newer version: 62
Show newest version
/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed 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 io.undertow.util;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Constructor;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.AccessController;
import java.security.PrivilegedExceptionAction;

/**
 * An efficient and flexible Base64 implementation.
 *
 * This class can deal with both MIME Base64 and Base64url.
 *
 * @author Jason T. Greene
 */
public class FlexBase64 {
    /*
     * Note that this code heavily favors performance over reuse and clean style.
     */

    private static final byte[] STANDARD_ENCODING_TABLE;
    private static final byte[] STANDARD_DECODING_TABLE = new byte[80];
    private static final byte[] URL_ENCODING_TABLE;
    private static final byte[] URL_DECODING_TABLE = new byte[80];
    private static final Constructor STRING_CONSTRUCTOR;

    static {
        STANDARD_ENCODING_TABLE = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".getBytes(StandardCharsets.US_ASCII);
        URL_ENCODING_TABLE = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_".getBytes(StandardCharsets.US_ASCII);

        for (int i = 0; i < STANDARD_ENCODING_TABLE.length; i++) {
            int v = (STANDARD_ENCODING_TABLE[i] & 0xFF) - 43;
            STANDARD_DECODING_TABLE[v] = (byte)(i + 1);  // zero = illegal
        }

        for (int i = 0; i < URL_ENCODING_TABLE.length; i++) {
            int v = (URL_ENCODING_TABLE[i] & 0xFF) - 43;
            URL_DECODING_TABLE[v] = (byte)(i + 1);  // zero = illegal
        }


        Constructor c = null;
        try {
            PrivilegedExceptionAction> runnable = new PrivilegedExceptionAction>() {
                @Override
                public Constructor run() throws Exception {
                    Constructor c;
                    c = String.class.getDeclaredConstructor(char[].class, boolean.class);
                    c.setAccessible(true);
                    return c;
                }
            };
            if (System.getSecurityManager() != null) {
                c = AccessController.doPrivileged(runnable);
            } else {
                c = runnable.run();
            }
        } catch (Throwable t) {
        }

        STRING_CONSTRUCTOR = c;
    }

    /**
     * Creates a state driven base64 encoder.
     *
     * 

The Encoder instance is not thread-safe, and must not be shared between threads without establishing a * happens-before relationship.

* * @param wrap whether or not to wrap at 76 characters with CRLF * @return an createEncoder instance */ public static Encoder createEncoder(boolean wrap) { return new Encoder(wrap, false); } /** * Creates a state driven base64url encoder. * *

The Encoder instance is not thread-safe, and must not be shared between threads without establishing a * happens-before relationship.

* * @param wrap whether or not to wrap at 76 characters with CRLF * @return an createEncoder instance */ public static Encoder createURLEncoder(boolean wrap) { return new Encoder(wrap, true); } /** * Creates a state driven base64 decoder. * *

The Decoder instance is not thread-safe, and must not be shared between threads without establishing a * happens-before relationship.

* * @return a new createDecoder instance */ public static Decoder createDecoder() { return new Decoder(false); } /** * Creates a state driven base64url decoder. * *

The Decoder instance is not thread-safe, and must not be shared between threads without establishing a * happens-before relationship.

* * @return a new createDecoder instance */ public static Decoder createURLDecoder() { return new Decoder(true); } /** * Encodes a fixed and complete byte array into a Base64 String. * *

This method is only useful for applications which require a String and have all data to be encoded up-front. * Note that byte arrays or buffers are almost always a better storage choice. They consume half the memory and * can be reused (modified). In other words, it is almost always better to use {@link #encodeBytes}, * {@link #createEncoder}, or {@link #createEncoderOutputStream} instead. * instead. * * @param source the byte array to encode from * @param wrap whether or not to wrap the output at 76 chars with CRLFs * @return a new String representing the Base64 output */ public static String encodeString(byte[] source, boolean wrap) { return Encoder.encodeString(source, 0, source.length, wrap, false); } /** * Encodes a fixed and complete byte array into a Base64url String. * *

This method is only useful for applications which require a String and have all data to be encoded up-front. * Note that byte arrays or buffers are almost always a better storage choice. They consume half the memory and * can be reused (modified). In other words, it is almost always better to use {@link #encodeBytes}, * {@link #createEncoder}, or {@link #createEncoderOutputStream} instead. * instead. * * @param source the byte array to encode from * @param wrap whether or not to wrap the output at 76 chars with CRLFs * @return a new String representing the Base64url output */ public static String encodeStringURL(byte[] source, boolean wrap) { return Encoder.encodeString(source, 0, source.length, wrap, true); } /** * Encodes a fixed and complete byte array into a Base64 String. * *

This method is only useful for applications which require a String and have all data to be encoded up-front. * Note that byte arrays or buffers are almost always a better storage choice. They consume half the memory and * can be reused (modified). In other words, it is almost always better to use {@link #encodeBytes}, * {@link #createEncoder}, or {@link #createEncoderOutputStream} instead.

* *

     *    // Encodes "ell"
     *    FlexBase64.encodeString("hello".getBytes("US-ASCII"), 1, 4);
     * 
* * @param source the byte array to encode from * @param pos the position to start encoding from * @param limit the position to halt encoding at (exclusive) * @param wrap whether or not to wrap the output at 76 chars with CRLFs * @return a new String representing the Base64 output */ public static String encodeString(byte[] source, int pos, int limit, boolean wrap) { return Encoder.encodeString(source, pos, limit, wrap, false); } /** * Encodes a fixed and complete byte array into a Base64url String. * *

This method is only useful for applications which require a String and have all data to be encoded up-front. * Note that byte arrays or buffers are almost always a better storage choice. They consume half the memory and * can be reused (modified). In other words, it is almost always better to use {@link #encodeBytes}, * {@link #createEncoder}, or {@link #createEncoderOutputStream} instead.

* *

     *    // Encodes "ell"
     *    FlexBase64.encodeStringURL("hello".getBytes("US-ASCII"), 1, 4);
     * 
* * @param source the byte array to encode from * @param pos the position to start encoding from * @param limit the position to halt encoding at (exclusive) * @param wrap whether or not to wrap the output at 76 chars with CRLFs * @return a new String representing the Base64url output */ public static String encodeStringURL(byte[] source, int pos, int limit, boolean wrap) { return Encoder.encodeString(source, pos, limit, wrap, true); } /** * Encodes a fixed and complete byte buffer into a Base64 String. * *

This method is only useful for applications which require a String and have all data to be encoded up-front. * Note that byte arrays or buffers are almost always a better storage choice. They consume half the memory and * can be reused (modified). In other words, it is almost always better to use {@link #encodeBytes}, * {@link #createEncoder}, or {@link #createEncoderOutputStream} instead.

* *

     *    // Encodes "hello"
     *    FlexBase64.encodeString(ByteBuffer.wrap("hello".getBytes("US-ASCII")), false);
     * 
* * @param source the byte buffer to encode from * @param wrap whether or not to wrap the output at 76 chars with CRLFs * @return a new String representing the Base64 output */ public static String encodeString(ByteBuffer source, boolean wrap) { return Encoder.encodeString(source, wrap, false); } /** * Encodes a fixed and complete byte buffer into a Base64url String. * *

This method is only useful for applications which require a String and have all data to be encoded up-front. * Note that byte arrays or buffers are almost always a better storage choice. They consume half the memory and * can be reused (modified). In other words, it is almost always better to use {@link #encodeBytes}, * {@link #createEncoder}, or {@link #createEncoderOutputStream} instead.

* *

     *    // Encodes "hello"
     *    FlexBase64.encodeStringURL(ByteBuffer.wrap("hello".getBytes("US-ASCII")), false);
     * 
* * @param source the byte buffer to encode from * @param wrap whether or not to wrap the output at 76 chars with CRLFs * @return a new String representing the Base64url output */ public static String encodeStringURL(ByteBuffer source, boolean wrap) { return Encoder.encodeString(source, wrap, true); } /** * Encodes a fixed and complete byte buffer into a Base64 byte array. * *

     *    // Encodes "ell"
     *    FlexBase64.encodeString("hello".getBytes("US-ASCII"), 1, 4, false);
     * 
* * @param source the byte array to encode from * @param pos the position to start encoding at * @param limit the position to halt encoding at (exclusive) * @param wrap whether or not to wrap at 76 characters with CRLFs * @return a new byte array containing the encoded ASCII values */ public static byte[] encodeBytes(byte[] source, int pos, int limit, boolean wrap) { return Encoder.encodeBytes(source, pos, limit, wrap, false); } /** * Encodes a fixed and complete byte buffer into a Base64url byte array. * *

     *    // Encodes "ell"
     *    FlexBase64.encodeStringURL("hello".getBytes("US-ASCII"), 1, 4, false);
     * 
* * @param source the byte array to encode from * @param pos the position to start encoding at * @param limit the position to halt encoding at (exclusive) * @param wrap whether or not to wrap at 76 characters with CRLFs * @return a new byte array containing the encoded ASCII values */ public static byte[] encodeBytesURL(byte[] source, int pos, int limit, boolean wrap) { return Encoder.encodeBytes(source, pos, limit, wrap, true); } /** * Decodes a Base64 encoded string into a new byte buffer. The returned byte buffer is a heap buffer, * and it is therefor possible to retrieve the backing array using {@link java.nio.ByteBuffer#array()}, * {@link java.nio.ByteBuffer#arrayOffset()} and {@link java.nio.ByteBuffer#limit()}. The latter is very * important since the decoded array may be larger than the decoded data. This is due to length estimation which * avoids an unnecessary array copy. * * @param source the Base64 string to decode * @return a byte buffer containing the decoded output * @throws IOException if the encoding is invalid or corrupted */ public static ByteBuffer decode(String source) throws IOException { return Decoder.decode(source, false); } /** * Decodes a Base64url encoded string into a new byte buffer. The returned byte buffer is a heap buffer, * and it is therefor possible to retrieve the backing array using {@link java.nio.ByteBuffer#array()}, * {@link java.nio.ByteBuffer#arrayOffset()} and {@link java.nio.ByteBuffer#limit()}. The latter is very * important since the decoded array may be larger than the decoded data. This is due to length estimation which * avoids an unnecessary array copy. * * @param source the Base64 string to decode * @return a byte buffer containing the decoded output * @throws IOException if the encoding is invalid or corrupted */ public static ByteBuffer decodeURL(String source) throws IOException { return Decoder.decode(source, true); } /** * Decodes a Base64 encoded byte buffer into a new byte buffer. The returned byte buffer is a heap buffer, * and it is therefor possible to retrieve the backing array using {@link java.nio.ByteBuffer#array()}, * {@link java.nio.ByteBuffer#arrayOffset()} and {@link java.nio.ByteBuffer#limit()}. The latter is very * important since the decoded array may be larger than the decoded data. This is due to length estimation which * avoids an unnecessary array copy. * * @param source the Base64 content to decode * @return a byte buffer containing the decoded output * @throws IOException if the encoding is invalid or corrupted */ public static ByteBuffer decode(ByteBuffer source) throws IOException { return Decoder.decode(source, false); } /** * Decodes a Base64url encoded byte buffer into a new byte buffer. The returned byte buffer is a heap buffer, * and it is therefor possible to retrieve the backing array using {@link java.nio.ByteBuffer#array()}, * {@link java.nio.ByteBuffer#arrayOffset()} and {@link java.nio.ByteBuffer#limit()}. The latter is very * important since the decoded array may be larger than the decoded data. This is due to length estimation which * avoids an unnecessary array copy. * * @param source the Base64 content to decode * @return a byte buffer containing the decoded output * @throws IOException if the encoding is invalid or corrupted */ public static ByteBuffer decodeURL(ByteBuffer source) throws IOException { return Decoder.decode(source, true); } /** * Decodes a Base64 encoded byte array into a new byte buffer. The returned byte buffer is a heap buffer, * and it is therefor possible to retrieve the backing array using {@link java.nio.ByteBuffer#array()}, * {@link java.nio.ByteBuffer#arrayOffset()} and {@link java.nio.ByteBuffer#limit()}. The latter is very * important since the decoded array may be larger than the decoded data. This is due to length estimation which * avoids an unnecessary array copy. * * @param source the Base64 content to decode * @param off position to start decoding from in source * @param limit position to stop decoding in source (exclusive) * @return a byte buffer containing the decoded output * @throws IOException if the encoding is invalid or corrupted */ public static ByteBuffer decode(byte[] source, int off, int limit) throws IOException { return Decoder.decode(source, off, limit, false); } /** * Decodes a Base64url encoded byte array into a new byte buffer. The returned byte buffer is a heap buffer, * and it is therefor possible to retrieve the backing array using {@link java.nio.ByteBuffer#array()}, * {@link java.nio.ByteBuffer#arrayOffset()} and {@link java.nio.ByteBuffer#limit()}. The latter is very * important since the decoded array may be larger than the decoded data. This is due to length estimation which * avoids an unnecessary array copy. * * @param source the Base64url content to decode * @param off position to start decoding from in source * @param limit position to stop decoding in source (exclusive) * @return a byte buffer containing the decoded output * @throws IOException if the encoding is invalid or corrupted */ public static ByteBuffer decodeURL(byte[] source, int off, int limit) throws IOException { return Decoder.decode(source, off, limit, true); } /** * Creates an InputStream wrapper which encodes a source into base64 as it is read, until the source hits EOF. * Upon hitting EOF, a standard base64 termination sequence will be readable. Clients can simply treat this input * stream as if they were reading from a base64 encoded file. This stream attempts to read and encode in buffer * size chunks from the source, in order to improve overall performance. Thus, BufferInputStream is not necessary * and will lead to double buffering. * *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param source an input source to read from * @param bufferSize the chunk size to buffer from the source * @param wrap whether or not the stream should wrap base64 output at 76 characters * @return an encoded input stream instance. */ public static EncoderInputStream createEncoderInputStream(InputStream source, int bufferSize, boolean wrap) { return new EncoderInputStream(source, bufferSize, wrap, false); } /** * Creates an InputStream wrapper which encodes a source into base64 as it is read, until the source hits EOF. * Upon hitting EOF, a standard base64 termination sequence will be readable. Clients can simply treat this input * stream as if they were reading from a base64 encoded file. This stream attempts to read and encode in 8192 byte * chunks. Thus, BufferedInputStream is not necessary as a source and will lead to double buffering. * *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param source an input source to read from * @return an encoded input stream instance. */ public static EncoderInputStream createEncoderInputStream(InputStream source) { return new EncoderInputStream(source); } /** * Creates an InputStream wrapper which decodes a base64 input source into the decoded content as it is read, * until the source hits EOF. Upon hitting EOF, a standard base64 termination sequence will be readable. * Clients can simply treat this input stream as if they were reading from a base64 encoded file. This stream * attempts to read and encode in buffer size byte chunks. Thus, BufferedInputStream is not necessary * as a source and will lead to double buffering. * *

Note that the end of a base64 stream can not reliably be detected, so if multiple base64 streams exist on the * wire, the source stream will need to simulate an EOF when the boundary mechanism is detected.

* *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param source an input source to read from * @param bufferSize the chunk size to buffer before when reading from the target * @return a decoded input stream instance. */ public static DecoderInputStream createDecoderInputStream(InputStream source, int bufferSize) { return new DecoderInputStream(source, bufferSize); } /** * Creates an InputStream wrapper which decodes a base64 input source into the decoded content as it is read, * until the source hits EOF. Upon hitting EOF, a standard base64 termination sequence will be readable. * Clients can simply treat this input stream as if they were reading from a base64 encoded file. This stream * attempts to read and encode in 8192 byte chunks. Thus, BufferedInputStream is not necessary * as a source and will lead to double buffering. * *

Note that the end of a base64 stream can not reliably be detected, so if multiple base64 streams exist on the * wire, the source stream will need to simulate an EOF when the boundary mechanism is detected.

* *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param source an input source to read from * @return a decoded input stream instance. */ public static DecoderInputStream createDecoderInputStream(InputStream source) { return new DecoderInputStream(source); } /** * Creates an OutputStream wrapper which base64 encodes and writes to the passed OutputStream target. When this * stream is closed base64 padding will be added if needed. Alternatively if this represents an "inner stream", * the {@link FlexBase64.EncoderOutputStream#complete()} method can be called to close out * the inner stream without closing the wrapped target. * *

All bytes written will be queued to a buffer in the specified size. This stream, therefore, does not require * BufferedOutputStream, which would lead to double buffering. * * @param target an output target to write to * @param bufferSize the chunk size to buffer before writing to the target * @param wrap whether or not the stream should wrap base64 output at 76 characters * @return an encoded output stream instance. */ public static EncoderOutputStream createEncoderOutputStream(OutputStream target, int bufferSize, boolean wrap) { return new EncoderOutputStream(target, bufferSize, wrap); } /** * Creates an OutputStream wrapper which base64 encodes and writes to the passed OutputStream target. When this * stream is closed base64 padding will be added if needed. Alternatively if this represents an "inner stream", * the {@link FlexBase64.EncoderOutputStream#complete()} method can be called to close out * the inner stream without closing the wrapped target. * *

All bytes written will be queued to an 8192 byte buffer. This stream, therefore, does not require * BufferedOutputStream, which would lead to double buffering.

* *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param output the output stream to write encoded output to * @return an encoded output stream instance. */ public static EncoderOutputStream createEncoderOutputStream(OutputStream output) { return new EncoderOutputStream(output); } /** * Creates an OutputStream wrapper which decodes base64 content before writing to the passed OutputStream target. * *

All bytes written will be queued to a buffer using the specified buffer size. This stream, therefore, does * not require BufferedOutputStream, which would lead to double buffering.

* *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param output the output stream to write decoded output to * @param bufferSize the buffer size to buffer writes to * @return a decoded output stream instance. */ public static DecoderOutputStream createDecoderOutputStream(OutputStream output, int bufferSize) { return new DecoderOutputStream(output, bufferSize); } /** * Creates an OutputStream wrapper which decodes base64 content before writing to the passed OutputStream target. * *

All bytes written will be queued to an 8192 byte buffer. This stream, therefore, does * not require BufferedOutputStream, which would lead to double buffering.

* *

This stream is not thread-safe, and should not be shared between threads, without establishing a * happens-before relationship.

* * @param output the output stream to write decoded output to * @return a decoded output stream instance. */ public static DecoderOutputStream createDecoderOutputStream(OutputStream output) { return new DecoderOutputStream(output); } /** * Controls the encoding process. */ public static final class Encoder { private int state; private int last; private int count; private final boolean wrap; private int lastPos; private final byte[] encodingTable; private Encoder(boolean wrap, boolean url) { this.wrap = wrap; this.encodingTable = url ? URL_ENCODING_TABLE : STANDARD_ENCODING_TABLE; } /** * Encodes bytes read from source and writes them in base64 format to target. If the source limit is hit, this * method will return and save the current state, such that future calls can resume the encoding process. * In addition, if the target does not have the capacity to fit an entire quad of bytes, this method will also * return and save state for subsequent calls to this method. Once all bytes have been encoded to the target, * {@link #complete(java.nio.ByteBuffer)} should be called to add the necessary padding characters. * * @param source the byte buffer to read from * @param target the byte buffer to write to */ public void encode(ByteBuffer source, ByteBuffer target) { if (target == null) throw new IllegalStateException(); int last = this.last; int state = this.state; boolean wrap = this.wrap; int count = this.count; final byte[] ENCODING_TABLE = encodingTable; int remaining = source.remaining(); while (remaining > 0) { // Unrolled state machine for performance (resumes and executes all states in one iteration) int require = 4 - state; require = wrap && (count >= 72) ? require + 2 : require; if (target.remaining() < require) { break; } // ( 6 | 2) (4 | 4) (2 | 6) int b = source.get() & 0xFF; if (state == 0) { target.put(ENCODING_TABLE[b >>> 2]); last = (b & 0x3) << 4; state++; if (--remaining <= 0) { break; } b = source.get() & 0xFF; } if (state == 1) { target.put(ENCODING_TABLE[last | (b >>> 4)]); last = (b & 0x0F) << 2; state++; if (--remaining <= 0) { break; } b = source.get() & 0xFF; } if (state == 2) { target.put(ENCODING_TABLE[last | (b >>> 6)]); target.put(ENCODING_TABLE[b & 0x3F]); last = state = 0; remaining--; } if (wrap) { count += 4; if (count >= 76) { count = 0; target.putShort((short)0x0D0A); } } } this.count = count; this.last = last; this.state = state; this.lastPos = source.position(); } /** * Encodes bytes read from source and writes them in base64 format to target. If the source limit is hit, this * method will return and save the current state, such that future calls can resume the encoding process. * In addition, if the target does not have the capacity to fit an entire quad of bytes, this method will also * return and save state for subsequent calls to this method. Once all bytes have been encoded to the target, * {@link #complete(byte[], int)} should be called to add the necessary padding characters. In order to * determine the last read position, the {@link #getLastInputPosition()} can be used. * *

Note that the limit values are not lengths, they are positions similar to * {@link java.nio.ByteBuffer#limit()}. To calculate a length simply subtract position from limit.

* *

         *  Encoder encoder = FlexBase64.createEncoder(false);
         *  byte[] outBuffer = new byte[10];
         *  // Encode "ell"
         *  int outPosition = encoder.encode("hello".getBytes("US-ASCII"), 1, 4, outBuffer, 5, 10);
         *  // Prints "9 : ZWxs"
         *  System.out.println(outPosition + " : " + new String(outBuffer, 0, 5, outPosition - 5));
         * 
* * @param source the byte array to read from * @param pos ths position in the byte array to start reading from * @param limit the position in the byte array that is after the end of the source data * @param target the byte array to write base64 bytes to * @param opos the position to start writing to the target array at * @param olimit the position in the target byte array that makes the end of the writable area (exclusive) * @return the position in the target array immediately following the last byte written */ public int encode(byte[] source, int pos, int limit, byte[] target, int opos, int olimit) { if (target == null) throw new IllegalStateException(); int last = this.last; int state = this.state; int count = this.count; boolean wrap = this.wrap; final byte[] ENCODING_TABLE = encodingTable; while (limit > pos) { // Unrolled state machine for performance (resumes and executes all states in one iteration) int require = 4 - state; require = wrap && count >= 72 ? require + 2 : require; if ((require + opos) > olimit) { break; } // ( 6 | 2) (4 | 4) (2 | 6) int b = source[pos++] & 0xFF; if (state == 0) { target[opos++] = ENCODING_TABLE[b >>> 2]; last = (b & 0x3) << 4; state++; if (pos >= limit) { break; } b = source[pos++] & 0xFF; } if (state == 1) { target[opos++] = ENCODING_TABLE[last | (b >>> 4)]; last = (b & 0x0F) << 2; state++; if (pos >= limit) { break; } b = source[pos++] & 0xFF; } if (state == 2) { target[opos++] = ENCODING_TABLE[last | (b >>> 6)]; target[opos++] = ENCODING_TABLE[b & 0x3F]; last = state = 0; } if (wrap) { count += 4; if (count >= 76) { count = 0; target[opos++] = 0x0D; target[opos++] = 0x0A; } } } this.count = count; this.last = last; this.state = state; this.lastPos = pos; return opos; } private static String encodeString(byte[] source, int pos, int limit, boolean wrap, boolean url) { int olimit = (limit - pos); int remainder = olimit % 3; olimit = (olimit + (remainder == 0 ? 0 : 3 - remainder)) / 3 * 4; olimit += (wrap ? (olimit / 76) * 2 + 2 : 0); char[] target = new char[olimit]; int opos = 0; int last = 0; int count = 0; int state = 0; final byte[] ENCODING_TABLE = url ? URL_ENCODING_TABLE : STANDARD_ENCODING_TABLE; while (limit > pos) { // ( 6 | 2) (4 | 4) (2 | 6) int b = source[pos++] & 0xFF; target[opos++] = (char) ENCODING_TABLE[b >>> 2]; last = (b & 0x3) << 4; if (pos >= limit) { state = 1; break; } b = source[pos++] & 0xFF; target[opos++] = (char) ENCODING_TABLE[last | (b >>> 4)]; last = (b & 0x0F) << 2; if (pos >= limit) { state = 2; break; } b = source[pos++] & 0xFF; target[opos++] = (char) ENCODING_TABLE[last | (b >>> 6)]; target[opos++] = (char) ENCODING_TABLE[b & 0x3F]; if (wrap) { count += 4; if (count >= 76) { count = 0; target[opos++] = 0x0D; target[opos++] = 0x0A; } } } complete(target, opos, state, last, wrap, url); try { // Eliminate copying on Open/Oracle JDK if (STRING_CONSTRUCTOR != null) { return STRING_CONSTRUCTOR.newInstance(target, Boolean.TRUE); } } catch (Exception e) { // Ignoring on purpose } return new String(target); } private static byte[] encodeBytes(byte[] source, int pos, int limit, boolean wrap, boolean url) { int olimit = (limit - pos); int remainder = olimit % 3; olimit = (olimit + (remainder == 0 ? 0 : 3 - remainder)) / 3 * 4; olimit += (wrap ? (olimit / 76) * 2 + 2 : 0); byte[] target = new byte[olimit]; int opos = 0; int count = 0; int last = 0; int state = 0; final byte[] ENCODING_TABLE = url ? URL_ENCODING_TABLE : STANDARD_ENCODING_TABLE; while (limit > pos) { // ( 6 | 2) (4 | 4) (2 | 6) int b = source[pos++] & 0xFF; target[opos++] = ENCODING_TABLE[b >>> 2]; last = (b & 0x3) << 4; if (pos >= limit) { state = 1; break; } b = source[pos++] & 0xFF; target[opos++] = ENCODING_TABLE[last | (b >>> 4)]; last = (b & 0x0F) << 2; if (pos >= limit) { state = 2; break; } b = source[pos++] & 0xFF; target[opos++] = ENCODING_TABLE[last | (b >>> 6)]; target[opos++] = ENCODING_TABLE[b & 0x3F]; if (wrap) { count += 4; if (count >= 76) { count = 0; target[opos++] = 0x0D; target[opos++] = 0x0A; } } } complete(target, opos, state, last, wrap, url); return target; } private static String encodeString(ByteBuffer source, boolean wrap, boolean url) { int remaining = source.remaining(); int remainder = remaining % 3; int olimit = (remaining + (remainder == 0 ? 0 : 3 - remainder)) / 3 * 4; olimit += (wrap ? olimit / 76 * 2 + 2 : 0); char[] target = new char[olimit]; int opos = 0; int last = 0; int state = 0; int count = 0; final byte[] ENCODING_TABLE = url ? URL_ENCODING_TABLE : STANDARD_ENCODING_TABLE; while (remaining > 0) { // ( 6 | 2) (4 | 4) (2 | 6) int b = source.get() & 0xFF; target[opos++] = (char) ENCODING_TABLE[b >>> 2]; last = (b & 0x3) << 4; if (--remaining <= 0) { state = 1; break; } b = source.get() & 0xFF; target[opos++] = (char) ENCODING_TABLE[last | (b >>> 4)]; last = (b & 0x0F) << 2; if (--remaining <= 0) { state = 2; break; } b = source.get() & 0xFF; target[opos++] = (char) ENCODING_TABLE[last | (b >>> 6)]; target[opos++] = (char) ENCODING_TABLE[b & 0x3F]; remaining--; if (wrap) { count += 4; if (count >= 76) { count = 0; target[opos++] = 0x0D; target[opos++] = 0x0A; } } } complete(target, opos, state, last, wrap, url); try { // Eliminate copying on Open/Oracle JDK if (STRING_CONSTRUCTOR != null) { return STRING_CONSTRUCTOR.newInstance(target, Boolean.TRUE); } } catch (Exception e) { // Ignoring on purpose } return new String(target); } /** * Gets the last position where encoding left off in the last byte array that was used. * If the target for encoded content does not have the necessary capacity, this method should be used to * determine where to start from on subsequent reads. * * @return the last known read position */ public int getLastInputPosition() { return lastPos; } /** * Completes an encoding session by writing out the necessary padding. This is essential to complying * with the Base64 format. This method will write at most 4 or 2 bytes starting at pos,depending on * whether or not wrapping is enabled. * *

         *  Encoder encoder = FlexBase64.createEncoder(false);
         *  byte[] outBuffer = new byte[13];
         *
         *  // Encodes "ello"
         *  int outPosition = encoder.encode("hello".getBytes("US-ASCII"), 0, 4, outBuffer, 5, 13);
         *  outPosition = encoder.complete(outBuffer, outPosition);
         *
         *  // Prints "13 : aGVsbA=="
         *  System.out.println(outPosition + " : " + new String(outBuffer, 0, 5, outPosition - 5));
         * 
* * @param target the byte array to write to * @param pos the position to start writing at * @return the position after the last byte written */ public int complete(byte[] target, int pos) { if (state > 0) { target[pos++] = encodingTable[last]; for (int i = state; i < 3; i++) { target[pos++] = (byte)'='; } last = state = 0; } if (wrap) { target[pos++] = 0x0D; target[pos++] = 0x0A; } return pos; } private static int complete(char[] target, int pos, int state, int last, boolean wrap, boolean url) { if (state > 0) { target[pos++] = (char) (url ? URL_ENCODING_TABLE : STANDARD_ENCODING_TABLE)[last]; for (int i = state; i < 3; i++) { target[pos++] = '='; } } if (wrap) { target[pos++] = 0x0D; target[pos++] = 0x0A; } return pos; } private static int complete(byte[] target, int pos, int state, int last, boolean wrap, boolean url) { if (state > 0) { target[pos++] = (url ? URL_ENCODING_TABLE : STANDARD_ENCODING_TABLE)[last]; for (int i = state; i < 3; i++) { target[pos++] = '='; } } if (wrap) { target[pos++] = 0x0D; target[pos++] = 0x0A; } return pos; } /** * Completes an encoding session by writing out the necessary padding. This is essential to complying * with the Base64 format. This method will write at most 4 or 2 bytes, depending on whether or not wrapping * is enabled. * * @param target the byte buffer to write to */ public void complete(ByteBuffer target) { if (state > 0) { target.put(encodingTable[last]); for (int i = state; i < 3; i++) { target.put((byte)'='); } last = state = 0; } if (wrap) { target.putShort((short)0x0D0A); } count = 0; } } /** * Controls the decoding process. */ public static final class Decoder { private int state; private int last; private int lastPos; private final byte[] decodingTable; private static final int SKIP = 0x0FD00; private static final int MARK = 0x0FE00; private static final int DONE = 0x0FF00; private static final int ERROR = 0xF0000; private Decoder(boolean url) { this.decodingTable = url ? URL_DECODING_TABLE : STANDARD_DECODING_TABLE; } private int nextByte(ByteBuffer buffer, int state, int last, boolean ignoreErrors) throws IOException { return nextByte(buffer.get() & 0xFF, state, last, ignoreErrors); } private int nextByte(Object source, int pos, int state, int last, boolean ignoreErrors) throws IOException { int c; if (source instanceof byte[]) { c = ((byte[])source)[pos] & 0xFF; } else if (source instanceof String) { c = ((String)source).charAt(pos) & 0xFF; } else { throw new IllegalArgumentException(); } return nextByte(c, state, last, ignoreErrors); } private int nextByte(int c, int state, int last, boolean ignoreErrors) throws IOException { if (last == MARK) { if (c != '=') { throw new IOException("Expected padding character"); } return DONE; } if (c == '=') { if (state == 2) { return MARK; } else if (state == 3) { return DONE; } else { throw new IOException("Unexpected padding character"); } } if (c == ' ' || c == '\t' || c == '\r' || c == '\n') { return SKIP; } if (c < 43 || c > 122) { if (ignoreErrors) { return ERROR; } throw new IOException("Invalid base64 character encountered: " + c); } int b = (decodingTable[c - 43] & 0xFF) - 1; if (b < 0) { if (ignoreErrors) { return ERROR; } throw new IOException("Invalid base64 character encountered: " + c); } return b; } /** * Decodes one Base64 byte buffer into another. This method will return and save state * if the target does not have the required capacity. Subsequent calls with a new target will * resume reading where it last left off (the source buffer's position). Similarly not all of the * source data need be available, this method can be repetitively called as data is made available. * *

The decoder will skip white space, but will error if it detects corruption.

* * @param source the byte buffer to read encoded data from * @param target the byte buffer to write decoded data to * @throws IOException if the encoded data is corrupted */ public void decode(ByteBuffer source, ByteBuffer target) throws IOException { if (target == null) throw new IllegalStateException(); int last = this.last; int state = this.state; int remaining = source.remaining(); int targetRemaining = target.remaining(); int b = 0; while (remaining-- > 0 && targetRemaining > 0) { b = nextByte(source, state, last, false); if (b == MARK) { last = MARK; if (--remaining <= 0) { break; } b = nextByte(source, state, last, false); } if (b == DONE) { last = state = 0; break; } if (b == SKIP) { continue; } // ( 6 | 2) (4 | 4) (2 | 6) if (state == 0) { last = b << 2; state++; if (remaining-- <= 0) { break; } b = nextByte(source, state, last, false); if ((b & 0xF000) != 0) { source.position(source.position() - 1); continue; } } if (state == 1) { target.put((byte)(last | (b >>> 4))); last = (b & 0x0F) << 4; state++; if (remaining-- <= 0 || --targetRemaining <= 0) { break; } b = nextByte(source, state, last, false); if ((b & 0xF000) != 0) { source.position(source.position() - 1); continue; } } if (state == 2) { target.put((byte) (last | (b >>> 2))); last = (b & 0x3) << 6; state++; if (remaining-- <= 0 || --targetRemaining <= 0) { break; } b = nextByte(source, state, last, false); if ((b & 0xF000) != 0) { source.position(source.position() - 1); continue; } } if (state == 3) { target.put((byte)(last | b)); last = state = 0; targetRemaining--; } } if (remaining > 0) { drain(source, b, state, last); } this.last = last; this.state = state; this.lastPos = source.position(); } private void drain(ByteBuffer source, int b, int state, int last) { while (b != DONE && source.remaining() > 0) { try { b = nextByte(source, state, last, true); } catch (IOException e) { b = 0; } if (b == MARK) { last = MARK; continue; } // Not WS/pad if ((b & 0xF000) == 0) { source.position(source.position() - 1); break; } } if (b == DONE) { // SKIP one line of trailing whitespace while (source.remaining() > 0) { b = source.get(); if (b == '\n') { break; } else if (b != ' ' && b != '\t' && b != '\r') { source.position(source.position() - 1); break; } } } } private int drain(Object source, int pos, int limit, int b, int state, int last) { while (b != DONE && limit > pos) { try { b = nextByte(source, pos++, state, last, true); } catch (IOException e) { b = 0; } if (b == MARK) { last = MARK; continue; } // Not WS/pad if ((b & 0xF000) == 0) { pos--; break; } } if (b == DONE) { // SKIP one line of trailing whitespace while (limit > pos) { if (source instanceof byte[]) { b = ((byte[])source)[pos++] & 0xFF; } else if (source instanceof String) { b = ((String)source).charAt(pos++) & 0xFF; } else { throw new IllegalArgumentException(); } if (b == '\n') { break; } else if (b != ' ' && b != '\t' && b != '\r') { pos--; break; } } } return pos; } private int decode(Object source, int sourcePos, int sourceLimit, byte[] target, int targetPos, int targetLimit) throws IOException { if (target == null) throw new IllegalStateException(); int last = this.last; int state = this.state; int pos = sourcePos; int opos = targetPos; int limit = sourceLimit; int olimit = targetLimit; int b = 0; while (limit > pos && olimit > opos) { b = nextByte(source, pos++, state, last, false); if (b == MARK) { last = MARK; if (pos >= limit) { break; } b = nextByte(source, pos++, state, last, false); } if (b == DONE) { last = state = 0; break; } if (b == SKIP) { continue; } // ( 6 | 2) (4 | 4) (2 | 6) if (state == 0) { last = b << 2; state++; if (pos >= limit) { break; } b = nextByte(source, pos++, state, last, false); if ((b & 0xF000) != 0) { pos--; continue; } } if (state == 1) { target[opos++] = ((byte)(last | (b >>> 4))); last = (b & 0x0F) << 4; state++; if (pos >= limit || opos >= olimit) { break; } b = nextByte(source, pos++, state, last, false); if ((b & 0xF000) != 0) { pos--; continue; } } if (state == 2) { target[opos++] = ((byte) (last | (b >>> 2))); last = (b & 0x3) << 6; state++; if (pos >= limit || opos >= olimit) { break; } b = nextByte(source, pos++, state, last, false); if ((b & 0xF000) != 0) { pos--; continue; } } if (state == 3) { target[opos++] = ((byte)(last | b)); last = state = 0; } } if (limit > pos) { pos = drain(source, pos, limit, b, state, last); } this.last = last; this.state = state; this.lastPos = pos; return opos; } /** * Gets the last position where decoding left off in the last byte array that was used for reading. * If the target for decoded content does not have the necessary capacity, this method should be used to * determine where to start from on subsequent decode calls. * * @return the last known read position */ public int getLastInputPosition() { return lastPos; } /** * Decodes one Base64 byte array into another byte array. If the source limit is hit, this method will * return and save the current state, such that future calls can resume the decoding process. Likewise, * if the target does not have the capacity, this method will also return and save state for subsequent * calls to this method. * *

When multiple calls are made, {@link #getLastInputPosition()} should be used to determine what value * should be set for sourcePos. Likewise, the returned target position should be used as the targetPos * in a subsequent call.

* *

The decoder will skip white space, but will error if it detects corruption.

* * @param source a Base64 encoded string to decode data from * @param sourcePos the position in the source array to start decoding from * @param sourceLimit the position in the source array to halt decoding when hit (exclusive) * @param target the byte buffer to write decoded data to * @param targetPos the position in the target byte array to begin writing at * @param targetLimit the position in the target byte array to halt writing (exclusive) * @throws IOException if the encoded data is corrupted * @return the position in the target array immediately following the last byte written * */ public int decode(String source, int sourcePos, int sourceLimit, byte[] target, int targetPos, int targetLimit) throws IOException { return decode((Object)source, sourcePos, sourceLimit, target, targetPos, targetLimit); } /** * Decodes a Base64 encoded string into the passed byte array. This method will return and save state * if the target does not have the required capacity. Subsequent calls with a new target will * resume reading where it last left off (the source buffer's position). Similarly not all of the * source data need be available, this method can be repetitively called as data is made available. * *

Since this method variant assumes a position of 0 and a limit of the item length, * repeated calls will need fresh source and target values. {@link #decode(String, int, int, byte[], int, int)} * would be a better fit if you need reuse

* *

The decoder will skip white space, but will error if it detects corruption.

* * @param source a base64 encoded string to decode from * @param target a byte array to write to * @throws java.io.IOException if the base64 content is malformed * @return output position following the last written byte */ public int decode(String source, byte[] target) throws IOException { return decode(source, 0, source.length(), target, 0, target.length); } /** * Decodes one Base64 byte array into another byte array. If the source limit is hit, this method will * return and save the current state, such that future calls can resume the decoding process. Likewise, * if the target does not have the capacity, this method will also return and save state for subsequent * calls to this method. * *

When multiple calls are made, {@link #getLastInputPosition()} should be used to determine what value * should be set for sourcePos. Likewise, the returned target position should be used as the targetPos * in a subsequent call.

* *

The decoder will skip white space, but will error if it detects corruption.

* *

         *  Decoder decoder = FlexBase64.createDecoder();
         *  byte[] outBuffer = new byte[10];
         *  byte[] bytes = "aGVsbG8=".getBytes("US-ASCII");
         *  // Decode only 2 bytes
         *  int outPosition = decoder.decode(bytes, 0, 8, outBuffer, 5, 7);
         *  // Resume where we left off and get the rest
         *  outPosition = decoder.decode(bytes, decoder.getLastInputPosition(), 8, outBuffer, outPosition, 10);
         *  // Prints "10 : Hello"
         *  System.out.println(outPosition + " : " + new String(outBuffer, 0, 5, outPosition - 5));
         * 
* * * @param source the byte array to read encoded data from * @param sourcePos the position in the source array to start decoding from * @param sourceLimit the position in the source array to halt decoding when hit (exclusive) * @param target the byte buffer to write decoded data to * @param targetPos the position in the target byte array to begin writing at * @param targetLimit the position in the target byte array to halt writing (exclusive) * @throws IOException if the encoded data is corrupted * @return the position in the target array immediately following the last byte written */ public int decode(byte[] source, int sourcePos, int sourceLimit, byte[] target, int targetPos, int targetLimit) throws IOException { return decode((Object)source, sourcePos, sourceLimit, target, targetPos, targetLimit); } private static ByteBuffer decode(String source, boolean url) throws IOException { int remainder = source.length() % 4; int size = ((source.length() / 4) + (remainder == 0 ? 0 : 4 - remainder)) * 3; byte[] buffer = new byte[size]; int actual = new Decoder(url).decode(source, 0, source.length(), buffer, 0, size); return ByteBuffer.wrap(buffer, 0, actual); } private static ByteBuffer decode(byte[] source, int off, int limit, boolean url) throws IOException { int len = limit - off; int remainder = len % 4; int size = ((len / 4) + (remainder == 0 ? 0 : 4 - remainder)) * 3; byte[] buffer = new byte[size]; int actual = new Decoder(url).decode(source, off, limit, buffer, 0, size); return ByteBuffer.wrap(buffer, 0, actual); } private static ByteBuffer decode(ByteBuffer source, boolean url) throws IOException { int len = source.remaining(); int remainder = len % 4; int size = ((len / 4) + (remainder == 0 ? 0 : 4 - remainder)) * 3; ByteBuffer buffer = ByteBuffer.allocate(size); new Decoder(url).decode(source, buffer); buffer.flip(); return buffer; } } /** * An input stream which decodes bytes as they are read from a stream with Base64 encoded data. */ public static class DecoderInputStream extends InputStream { private final InputStream input; private final byte[] buffer; private final Decoder decoder = createDecoder(); private int pos = 0; private int limit = 0; private byte[] one; private DecoderInputStream(InputStream input) { this(input, 8192); } private DecoderInputStream(InputStream input, int bufferSize) { this.input = input; buffer = new byte[bufferSize]; } private int fill() throws IOException { byte[] buffer = this.buffer; int read = input.read(buffer, 0, buffer.length); pos = 0; limit = read; return read; } /** * {@inheritDoc} */ @Override public int read(byte[] b, int off, int len) throws IOException { for (;;) { byte[] source = buffer; int pos = this.pos; int limit = this.limit; boolean setPos = true; if (pos >= limit) { if (len > source.length) { source = new byte[len]; limit = input.read(source, 0, len); pos = 0; setPos = false; } else { limit = fill(); pos = 0; } if (limit == -1) { return -1; } } int requested = len + pos; limit = limit > requested ? requested : limit; int read = decoder.decode(source, pos, limit, b, off, off+len) - off; if (setPos) { this.pos = decoder.getLastInputPosition(); } if (read > 0) { return read; } } } /** * {@inheritDoc} */ @Override public int read() throws IOException { byte[] one = this.one; if (one == null) { one = this.one = new byte[1]; } int read = this.read(one, 0, 1); return read > 0 ? one[0] & 0xFF : -1; } /** * {@inheritDoc} */ @Override public void close() throws IOException { input.close(); } } /** * An input stream which encodes bytes as they are read from a stream. */ public static class EncoderInputStream extends InputStream { private final InputStream input; private final byte[] buffer; private final byte[] overflow = new byte[6]; private int overflowPos; private int overflowLimit; private final Encoder encoder; private int pos = 0; private int limit = 0; private byte[] one; private boolean complete; private EncoderInputStream(InputStream input) { this(input, 8192, true, false); } private EncoderInputStream(InputStream input, int bufferSize, boolean wrap, boolean url) { this.input = input; buffer = new byte[bufferSize]; this.encoder = new Encoder(wrap, url); } private int fill() throws IOException { byte[] buffer = this.buffer; int read = input.read(buffer, 0, buffer.length); pos = 0; limit = read; return read; } /** * {@inheritDoc} */ @Override public int read() throws IOException { byte[] one = this.one; if (one == null) { one = this.one = new byte[1]; } int read = this.read(one, 0, 1); return read > 0 ? one[0] & 0xFF : -1; } /** * {@inheritDoc} */ @Override public int read(byte[] b, int off, int len) throws IOException { byte[] buffer = this.buffer; byte[] overflow = this.overflow; int overflowPos = this.overflowPos; int overflowLimit = this.overflowLimit; boolean complete = this.complete; boolean wrap = encoder.wrap; int copy = 0; if (overflowPos < overflowLimit) { copy = copyOverflow(b, off, len, overflow, overflowPos, overflowLimit); if (len <= copy || complete) { return copy; } len -= copy; off += copy; } else if (complete) { return -1; } for (;;) { byte[] source = buffer; int pos = this.pos; int limit = this.limit; boolean setPos = true; if (pos >= limit) { if (len > source.length) { // If requested length exceeds buffer, allocate a new temporary buffer that will be // one block less than an exact encoded output. This is to handle partial quad carryover // from an earlier read. int adjust = (len / 4 * 3) - 3; if (wrap) { adjust -= adjust / 76 * 2 + 2; } source = new byte[adjust]; limit = input.read(source, 0, adjust); pos = 0; setPos = false; } else { limit = fill(); pos = 0; } if (limit <= 0) { this.complete = true; if (len < (wrap ? 4 : 2)) { overflowLimit = encoder.complete(overflow, 0); this.overflowLimit = overflowLimit; int ret = copyOverflow(b, off, len, overflow, 0, overflowLimit) + copy; return ret == 0 ? -1 : ret; } int ret = encoder.complete(b, off) - off + copy; return ret == 0 ? -1 : ret; } } if (len < (wrap ? 6 : 4)) { overflowLimit = encoder.encode(source, pos, limit, overflow, 0, overflow.length); this.overflowLimit = overflowLimit; this.pos = encoder.getLastInputPosition(); return copyOverflow(b, off, len, overflow, 0, overflowLimit) + copy; } int read = encoder.encode(source, pos, limit, b, off, off+len) - off; if (setPos) { this.pos = encoder.getLastInputPosition(); } if (read > 0) { return read + copy; } } } private int copyOverflow(byte[] b, int off, int len, byte[] overflow, int pos, int limit) { limit -= pos; len = limit <= len ? limit : len; System.arraycopy(overflow, pos, b, off, len); this.overflowPos = pos + len; return len; } } /** * An output stream which base64 encodes all passed data and writes it to the wrapped target output stream. * *

Closing this stream will result in the correct padding sequence being written. However, as * required by the OutputStream contract, the wrapped stream will also be closed. If this is not desired, * the {@link #complete()} method should be used.

*/ public static class EncoderOutputStream extends OutputStream { private final OutputStream output; private final byte[] buffer; private final Encoder encoder; private int pos = 0; private byte[] one; private EncoderOutputStream(OutputStream output) { this(output, 8192, true); } private EncoderOutputStream(OutputStream output, int bufferSize, boolean wrap) { this.output = output; this.buffer = new byte[bufferSize]; this.encoder = createEncoder(wrap); } /** * {@inheritDoc} */ @Override public void write(byte[] b, int off, int len) throws IOException { byte[] buffer = this.buffer; Encoder encoder = this.encoder; int pos = this.pos; int limit = off + len; int ipos = off; while (ipos < limit) { pos = encoder.encode(b, ipos, limit, buffer, pos, buffer.length); int last = encoder.getLastInputPosition(); if (last == ipos || pos >= buffer.length) { output.write(buffer, 0, pos); pos = 0; } ipos = last; } this.pos = pos; } /** * {@inheritDoc} */ @Override public void write(int b) throws IOException { byte[] one = this.one; if (one == null) { this.one = one = new byte[1]; } one[0] = (byte)b; write(one, 0, 1); } /** * {@inheritDoc} */ @Override public void flush() throws IOException { OutputStream output = this.output; output.write(buffer, 0, pos); output.flush(); } /** * Completes the stream, writing out base64 padding characters if needed. * * @throws IOException if the underlying stream throws one */ public void complete() throws IOException { OutputStream output = this.output; byte[] buffer = this.buffer; int pos = this.pos; boolean completed = false; if (buffer.length - pos >= (encoder.wrap ? 2 : 4)) { this.pos = encoder.complete(buffer, pos); completed = true; } flush(); if (!completed) { int len = encoder.complete(buffer, 0); output.write(buffer, 0, len); output.flush(); } } /** * {@inheritDoc} */ @Override public void close() throws IOException { try { complete(); } catch (IOException e) { // eat } try { output.flush(); } catch (IOException e) { // eat } output.close(); } } /** * An output stream which decodes base64 data written to it, and writes the decoded output to the * wrapped inner stream. */ public static class DecoderOutputStream extends OutputStream { private final OutputStream output; private final byte[] buffer; private final Decoder decoder; private int pos = 0; private byte[] one; private DecoderOutputStream(OutputStream output) { this(output, 8192); } private DecoderOutputStream(OutputStream output, int bufferSize) { this.output = output; this.buffer = new byte[bufferSize]; this.decoder = createDecoder(); } /** * {@inheritDoc} */ @Override public void write(byte[] b, int off, int len) throws IOException { byte[] buffer = this.buffer; Decoder decoder = this.decoder; int pos = this.pos; int limit = off + len; int ipos = off; while (ipos < limit) { pos = decoder.decode(b, ipos, limit, buffer, pos, buffer.length); int last = decoder.getLastInputPosition(); if (last == ipos || pos >= buffer.length) { output.write(buffer, 0, pos); pos = 0; } ipos = last; } this.pos = pos; } /** * {@inheritDoc} */ @Override public void write(int b) throws IOException { byte[] one = this.one; if (one == null) { this.one = one = new byte[1]; } one[0] = (byte)b; write(one, 0, 1); } /** * {@inheritDoc} */ @Override public void flush() throws IOException { OutputStream output = this.output; output.write(buffer, 0, pos); output.flush(); } /** * {@inheritDoc} */ @Override public void close() throws IOException { try { flush(); } catch (IOException e) { // eat } try { output.flush(); } catch (IOException e) { // eat } output.close(); } } }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy