Java tutorial
/* * (C) Copyright 2016 Nuxeo SA (http://nuxeo.com/) and others. * * 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. * * Contributors: * Vladimir Pasquier <vpasquier@nuxeo.com> */ package org.nuxeo.client.internals.util; import java.io.UnsupportedEncodingException; import java.nio.charset.Charset; import org.apache.commons.io.IOUtils; /** * @since 0.1 */ public class Base64 { /* ******** P U B L I C F I E L D S ******** */ /** No options specified. Value is zero. */ public final static int NO_OPTIONS = 0; /** Specify encoding. */ public final static int ENCODE = 1; /** Specify decoding. */ public final static int DECODE = 0; /** Specify that data should be gzip-compressed. */ public final static int GZIP = 2; /** Don't break lines when encoding (violates strict Base64 specification) */ public final static int DONT_BREAK_LINES = 8; /* ******** P R I V A T E F I E L D S ******** */ /** Maximum line length (76) of Base64 output. */ private final static int MAX_LINE_LENGTH = 76; /** The equals sign (=) as a byte. */ private final static byte EQUALS_SIGN = (byte) '='; /** The new line character (\n) as a byte. */ private final static byte NEW_LINE = (byte) '\n'; /** Preferred encoding. */ private final static String PREFERRED_ENCODING = "UTF-8"; /** The 64 valid Base64 values. */ private final static byte[] ALPHABET; private final static byte[] _NATIVE_ALPHABET = /* May be something funny like EBCDIC */ { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/' }; /** Determine which ALPHABET to use. */ static { byte[] __bytes; try { __bytes = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/" .getBytes(PREFERRED_ENCODING); } // end try catch (UnsupportedEncodingException use) { __bytes = _NATIVE_ALPHABET; // Fall back to native encoding } // end catch ALPHABET = __bytes; } // end static /** * Translates a Base64 value to either its 6-bit reconstruction value or a negative number indicating some other * meaning. **/ private final static byte[] DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8 -5, -5, // Whitespace: Tab and Linefeed -9, -9, // Decimal 11 - 12 -5, // Whitespace: Carriage Return -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26 -9, -9, -9, -9, -9, // Decimal 27 - 31 -5, // Whitespace: Space -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42 62, // Plus sign at decimal 43 -9, -9, -9, // Decimal 44 - 46 63, // Slash at decimal 47 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine -9, -9, -9, // Decimal 58 - 60 -1, // Equals sign at decimal 61 -9, -9, -9, // Decimal 62 - 64 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N' 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z' -9, -9, -9, -9, -9, -9, // Decimal 91 - 96 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm' 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z' -9, -9, -9, -9 // Decimal 123 - 126 /* * ,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 139 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal * 140 - 152 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // * Decimal 166 - 178 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal * 205 - 217 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // * Decimal 231 - 243 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255 */ }; // I think I end up not using the BAD_ENCODING indicator. // private final static byte BAD_ENCODING = -9; // Indicates error in encoding private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in encoding private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in encoding /** Defeats instantiation. */ private Base64() { } /* ******** E N C O D I N G M E T H O D S ******** */ /** * Encodes up to the first three bytes of array <var>threeBytes</var> and returns a four-byte array in Base64 * notation. The actual number of significant bytes in your array is given by <var>numSigBytes</var>. The array * <var>threeBytes</var> needs only be as big as <var>numSigBytes</var>. Code can reuse a byte array by passing a * four-byte array as <var>b4</var>. * * @param b4 A reusable byte array to reduce array instantiation * @param threeBytes the array to convert * @param numSigBytes the number of significant bytes in your array * @return four byte array in Base64 notation. * @since 1.5.1 */ private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes) { encode3to4(threeBytes, 0, numSigBytes, b4, 0); return b4; } // end encode3to4 /** * Encodes up to three bytes of the array <var>source</var> and writes the resulting four Base64 bytes to * <var>destination</var>. The source and destination arrays can be manipulated anywhere along their length by * specifying <var>srcOffset</var> and <var>destOffset</var>. This method does not check to make sure your arrays * are large enough to accomodate <var>srcOffset</var> + 3 for the <var>source</var> array or <var>destOffset</var> * + 4 for the <var>destination</var> array. The actual number of significant bytes in your array is given by * <var>numSigBytes</var>. * * @param source the array to convert * @param srcOffset the index where conversion begins * @param numSigBytes the number of significant bytes in your array * @param destination the array to hold the conversion * @param destOffset the index where output will be put * @return the <var>destination</var> array * @since 1.3 */ private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination, int destOffset) { // 1 2 3 // 01234567890123456789012345678901 Bit position // --------000000001111111122222222 Array position from threeBytes // --------| || || || | Six bit groups to index ALPHABET // >>18 >>12 >> 6 >> 0 Right shift necessary // 0x3f 0x3f 0x3f Additional AND // Create buffer with zero-padding if there are only one or two // significant bytes passed in the array. // We have to shift left 24 in order to flush out the 1's that appear // when Java treats a value as negative that is cast from a byte to an int. int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0) | (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0) | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0); switch (numSigBytes) { case 3: destination[destOffset] = ALPHABET[(inBuff >>> 18)]; destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f]; destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f]; destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f]; return destination; case 2: destination[destOffset] = ALPHABET[(inBuff >>> 18)]; destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f]; destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f]; destination[destOffset + 3] = EQUALS_SIGN; return destination; case 1: destination[destOffset] = ALPHABET[(inBuff >>> 18)]; destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f]; destination[destOffset + 2] = EQUALS_SIGN; destination[destOffset + 3] = EQUALS_SIGN; return destination; default: return destination; } // end switch } // end encode3to4 public static String encode(byte[] bytes) { return encodeBytes(bytes); } public static String encode(String content) { return encodeBytes(content.getBytes()); } public static String encode(String content, String charset) throws UnsupportedEncodingException { return encodeBytes(content.getBytes(charset)); } public static String encode(String content, Charset charset) { return encodeBytes(content.getBytes(charset)); } /** * Serializes an object and returns the Base64-encoded version of that serialized object. If the object cannot be * serialized or there is another error, the method will return <tt>null</tt>. The object is not GZip-compressed * before being encoded. * * @param serializableObject The object to encode * @return The Base64-encoded object * @since 1.4 */ public static String encodeObject(java.io.Serializable serializableObject) { return encodeObject(serializableObject, NO_OPTIONS); } // end encodeObject /** * Serializes an object and returns the Base64-encoded version of that serialized object. If the object cannot be * serialized or there is another error, the method will return <tt>null</tt>. * <p> * Valid options: * * <pre> * GZIP: gzip-compresses object before encoding it. * DONT_BREAK_LINES: don't break lines at 76 characters * <i>Note: Technically, this makes your encoding non-compliant.</i> * </pre> * <p> * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or * <p> * Example: <code>encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )</code> * * @param serializableObject The object to encode * @param options Specified options * @return The Base64-encoded object * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @since 2.0 */ public static String encodeObject(java.io.Serializable serializableObject, int options) { // Streams java.io.ByteArrayOutputStream baos = null; java.io.OutputStream b64os = null; java.io.ObjectOutputStream oos = null; java.util.zip.GZIPOutputStream gzos = null; // Isolate options int gzip = (options & GZIP); int dontBreakLines = (options & DONT_BREAK_LINES); try { // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream baos = new java.io.ByteArrayOutputStream(); b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines); // GZip? if (gzip == GZIP) { gzos = new java.util.zip.GZIPOutputStream(b64os); oos = new java.io.ObjectOutputStream(gzos); } // end if: gzip else oos = new java.io.ObjectOutputStream(b64os); oos.writeObject(serializableObject); } // end try catch (java.io.IOException e) { e.printStackTrace(); return null; } // end catch finally { IOUtils.closeQuietly(oos); IOUtils.closeQuietly(gzos); IOUtils.closeQuietly(b64os); IOUtils.closeQuietly(baos); } // end finally // Return value according to relevant encoding. try { return new String(baos.toByteArray(), PREFERRED_ENCODING); } // end try catch (UnsupportedEncodingException uue) { return new String(baos.toByteArray()); } // end catch } // end encode /** * Encodes a byte array into Base64 notation. Does not GZip-compress data. * * @param source The data to convert * @since 1.4 */ public static String encodeBytes(byte[] source) { return encodeBytes(source, 0, source.length, NO_OPTIONS); } // end encodeBytes /** * Encodes a byte array into Base64 notation. * <p> * Valid options: * * <pre> * GZIP: gzip-compresses object before encoding it. * DONT_BREAK_LINES: don't break lines at 76 characters * <i>Note: Technically, this makes your encoding non-compliant.</i> * </pre> * <p> * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or * <p> * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code> * * @param source The data to convert * @param options Specified options * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @since 2.0 */ public static String encodeBytes(byte[] source, int options) { return encodeBytes(source, 0, source.length, options); } // end encodeBytes /** * Encodes a byte array into Base64 notation. Does not GZip-compress data. * * @param source The data to convert * @param off Offset in array where conversion should begin * @param len Length of data to convert * @since 1.4 */ public static String encodeBytes(byte[] source, int off, int len) { return encodeBytes(source, off, len, NO_OPTIONS); } // end encodeBytes /** * Encodes a byte array into Base64 notation. * <p> * Valid options: * * <pre> * GZIP: gzip-compresses object before encoding it. * DONT_BREAK_LINES: don't break lines at 76 characters * <i>Note: Technically, this makes your encoding non-compliant.</i> * </pre> * <p> * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or * <p> * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code> * * @param source The data to convert * @param off Offset in array where conversion should begin * @param len Length of data to convert * @param options Specified options * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @since 2.0 */ public static String encodeBytes(byte[] source, int off, int len, int options) { // Isolate options int dontBreakLines = (options & DONT_BREAK_LINES); int gzip = (options & GZIP); // Compress? if (gzip == GZIP) { java.io.ByteArrayOutputStream baos = null; java.util.zip.GZIPOutputStream gzos = null; Base64.OutputStream b64os = null; try { // GZip -> Base64 -> ByteArray baos = new java.io.ByteArrayOutputStream(); b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines); gzos = new java.util.zip.GZIPOutputStream(b64os); gzos.write(source, off, len); gzos.close(); } // end try catch (java.io.IOException e) { e.printStackTrace(); return null; } // end catch finally { IOUtils.closeQuietly(gzos); IOUtils.closeQuietly(b64os); IOUtils.closeQuietly(baos); } // end finally // Return value according to relevant encoding. try { return new String(baos.toByteArray(), PREFERRED_ENCODING); } // end try catch (UnsupportedEncodingException uue) { return new String(baos.toByteArray()); } // end catch } // end if: compress // Else, don't compress. Better not to use streams at all then. else { // Convert option to boolean in way that code likes it. boolean breakLines = dontBreakLines == 0; int len43 = len * 4 / 3; byte[] outBuff = new byte[(len43) // Main 4:3 + ((len % 3) > 0 ? 4 : 0) // Account for padding + (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New lines int d = 0; int e = 0; int len2 = len - 2; int lineLength = 0; for (; d < len2; d += 3, e += 4) { encode3to4(source, d + off, 3, outBuff, e); lineLength += 4; if (breakLines && lineLength == MAX_LINE_LENGTH) { outBuff[e + 4] = NEW_LINE; e++; lineLength = 0; } // end if: end of line } // en dfor: each piece of array if (d < len) { encode3to4(source, d + off, len - d, outBuff, e); e += 4; } // end if: some padding needed // Return value according to relevant encoding. try { return new String(outBuff, 0, e, PREFERRED_ENCODING); } // end try catch (UnsupportedEncodingException uue) { return new String(outBuff, 0, e); } // end catch } // end else: don't compress } // end encodeBytes /* ******** D E C O D I N G M E T H O D S ******** */ /** * Decodes four bytes from array <var>source</var> and writes the resulting bytes (up to three of them) to * <var>destination</var>. The source and destination arrays can be manipulated anywhere along their length by * specifying <var>srcOffset</var> and <var>destOffset</var>. This method does not check to make sure your arrays * are large enough to accomodate <var>srcOffset</var> + 4 for the <var>source</var> array or <var>destOffset</var> * + 3 for the <var>destination</var> array. This method returns the actual number of bytes that were converted from * the Base64 encoding. * * @param source the array to convert * @param srcOffset the index where conversion begins * @param destination the array to hold the conversion * @param destOffset the index where output will be put * @return the number of decoded bytes converted * @since 1.3 */ private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset) { // Example: Dk== if (source[srcOffset + 2] == EQUALS_SIGN) { // Two ways to do the same thing. Don't know which way I like best. // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 ) // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 ); int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12); destination[destOffset] = (byte) (outBuff >>> 16); return 1; } // Example: DkL= else if (source[srcOffset + 3] == EQUALS_SIGN) { // Two ways to do the same thing. Don't know which way I like best. // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 ) // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 ) // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 ); int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12) | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6); destination[destOffset] = (byte) (outBuff >>> 16); destination[destOffset + 1] = (byte) (outBuff >>> 8); return 2; } // Example: DkLE else { try { // Two ways to do the same thing. Don't know which way I like best. // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 ) // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 ) // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 ) // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 ); int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12) | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6) | ((DECODABET[source[srcOffset + 3]] & 0xFF)); destination[destOffset] = (byte) (outBuff >> 16); destination[destOffset + 1] = (byte) (outBuff >> 8); destination[destOffset + 2] = (byte) (outBuff); return 3; } catch (ArrayIndexOutOfBoundsException e) { System.out.println("" + source[srcOffset] + ": " + (DECODABET[source[srcOffset]])); System.out.println("" + source[srcOffset + 1] + ": " + (DECODABET[source[srcOffset + 1]])); System.out.println("" + source[srcOffset + 2] + ": " + (DECODABET[source[srcOffset + 2]])); System.out.println("" + source[srcOffset + 3] + ": " + (DECODABET[source[srcOffset + 3]])); return -1; } // e nd catch } } // end decodeToBytes /** * Very low-level access to decoding ASCII characters in the form of a byte array. Does not support automatically * gunzipping or any other "fancy" features. * * @param source The Base64 encoded data * @param off The offset of where to begin decoding * @param len The length of characters to decode * @return decoded data * @since 1.3 */ public static byte[] decode(byte[] source, int off, int len) { int len34 = len * 3 / 4; byte[] outBuff = new byte[len34]; // Upper limit on size of output int outBuffPosn = 0; byte[] b4 = new byte[4]; int b4Posn = 0; int i = 0; byte sbiCrop = 0; byte sbiDecode = 0; for (i = off; i < off + len; i++) { sbiCrop = (byte) (source[i] & 0x7f); // Only the low seven bits sbiDecode = DECODABET[sbiCrop]; if (sbiDecode >= WHITE_SPACE_ENC) // White space, Equals sign or better { if (sbiDecode >= EQUALS_SIGN_ENC) { b4[b4Posn++] = sbiCrop; if (b4Posn > 3) { outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn); b4Posn = 0; // If that was the equals sign, break out of 'for' loop if (sbiCrop == EQUALS_SIGN) break; } // end if: quartet built } // end if: equals sign or better } // end if: white space, equals sign or better else { System.err.println("Bad Base64 input character at " + i + ": " + source[i] + "(decimal)"); return null; } // end else: } // each input character byte[] out = new byte[outBuffPosn]; System.arraycopy(outBuff, 0, out, 0, outBuffPosn); return out; } // end decode /** * Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it. * * @param s the string to decode * @return the decoded data * @since 1.4 */ public static byte[] decode(String s) { byte[] bytes; try { bytes = s.getBytes(PREFERRED_ENCODING); } // end try catch (UnsupportedEncodingException uee) { bytes = s.getBytes(); } // end catch // </change> // Decode bytes = decode(bytes, 0, bytes.length); // Check to see if it's gzip-compressed // GZIP Magic Two-Byte Number: 0x8b1f (35615) if (bytes != null && bytes.length >= 4) { int head = ((int) bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00); if (java.util.zip.GZIPInputStream.GZIP_MAGIC == head) { java.io.ByteArrayInputStream bais = null; java.util.zip.GZIPInputStream gzis = null; java.io.ByteArrayOutputStream baos = null; byte[] buffer = new byte[2048]; int length = 0; try { baos = new java.io.ByteArrayOutputStream(); bais = new java.io.ByteArrayInputStream(bytes); gzis = new java.util.zip.GZIPInputStream(bais); while ((length = gzis.read(buffer)) >= 0) { baos.write(buffer, 0, length); } // end while: reading input // No error? Get new bytes. bytes = baos.toByteArray(); } // end try catch (java.io.IOException e) { // Just return originally-decoded bytes } // end catch finally { IOUtils.closeQuietly(baos); IOUtils.closeQuietly(gzis); IOUtils.closeQuietly(bais); } // end finally } // end if: gzipped } // end if: bytes.length >= 2 return bytes; } // end decode /** * Attempts to decode Base64 data and deserialize a Java Object within. Returns <tt>null</tt> if there was an error. * * @param encodedObject The Base64 data to decode * @return The decoded and deserialized object * @since 1.5 */ public static Object decodeToObject(String encodedObject) { // Decode and gunzip if necessary byte[] objBytes = decode(encodedObject); java.io.ByteArrayInputStream bais = null; java.io.ObjectInputStream ois = null; Object obj = null; try { bais = new java.io.ByteArrayInputStream(objBytes); ois = new java.io.ObjectInputStream(bais); obj = ois.readObject(); } // end try catch (java.io.IOException e) { e.printStackTrace(); obj = null; } // end catch catch (ClassNotFoundException e) { e.printStackTrace(); obj = null; } // end catch finally { IOUtils.closeQuietly(bais); IOUtils.closeQuietly(ois); } // end finally return obj; } // end decodeObject /** * Convenience method for encoding data to a file. * * @param dataToEncode byte array of data to encode in base64 form * @param filename Filename for saving encoded data * @return <tt>true</tt> if successful, <tt>false</tt> otherwise * @since 2.1 */ public static boolean encodeToFile(byte[] dataToEncode, String filename) { boolean success = false; Base64.OutputStream bos = null; try { bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.ENCODE); bos.write(dataToEncode); success = true; } // end try catch (java.io.IOException e) { success = false; } // end catch: IOException finally { IOUtils.closeQuietly(bos); } // end finally return success; } // end encodeToFile /** * Convenience method for decoding data to a file. * * @param dataToDecode Base64-encoded data as a string * @param filename Filename for saving decoded data * @return <tt>true</tt> if successful, <tt>false</tt> otherwise * @since 2.1 */ public static boolean decodeToFile(String dataToDecode, String filename) { boolean success = false; Base64.OutputStream bos = null; try { bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.DECODE); bos.write(dataToDecode.getBytes(PREFERRED_ENCODING)); success = true; } // end try catch (java.io.IOException e) { success = false; } // end catch: IOException finally { IOUtils.closeQuietly(bos); } // end finally return success; } // end decodeToFile /** * Convenience method for reading a base64-encoded file and decoding it. * * @param filename Filename for reading encoded data * @return decoded byte array or null if unsuccessful * @since 2.1 */ public static byte[] decodeFromFile(String filename) { byte[] decodedData = null; Base64.InputStream bis = null; try { // Set up some useful variables java.io.File file = new java.io.File(filename); byte[] buffer = null; int length = 0; int numBytes = 0; // Check for size of file if (file.length() > Integer.MAX_VALUE) { System.err.println("File is too big for this convenience method (" + file.length() + " bytes)."); return null; } // end if: file too big for int index buffer = new byte[(int) file.length()]; // Open a stream bis = new Base64.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), Base64.DECODE); // Read until done while ((numBytes = bis.read(buffer, length, 4096)) >= 0) length += numBytes; // Save in a variable to return decodedData = new byte[length]; System.arraycopy(buffer, 0, decodedData, 0, length); } // end try catch (java.io.IOException e) { System.err.println("Error decoding from file " + filename); } // end catch: IOException finally { IOUtils.closeQuietly(bis); } // end finally return decodedData; } // end decodeFromFile /** * Convenience method for reading a binary file and base64-encoding it. * * @param filename Filename for reading binary data * @return base64-encoded string or null if unsuccessful * @since 2.1 */ public static String encodeFromFile(String filename) { String encodedData = null; Base64.InputStream bis = null; try { // Set up some useful variables java.io.File file = new java.io.File(filename); byte[] buffer = new byte[(int) (file.length() * 1.4)]; int length = 0; int numBytes = 0; // Open a stream bis = new Base64.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), Base64.ENCODE); // Read until done while ((numBytes = bis.read(buffer, length, 4096)) >= 0) length += numBytes; // Save in a variable to return encodedData = new String(buffer, 0, length, Base64.PREFERRED_ENCODING); } // end try catch (java.io.IOException e) { System.err.println("Error encoding from file " + filename); } // end catch: IOException finally { IOUtils.closeQuietly(bis); } // end finally return encodedData; } // end encodeFromFile /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */ /** * A {@link Base64.InputStream} will read data from another <tt>java.io.InputStream</tt>, given in the constructor, * and encode/decode to/from Base64 notation on the fly. * * @see Base64 * @since 1.3 */ public static class InputStream extends java.io.FilterInputStream { private boolean encode; // Encoding or decoding private int position; // Current position in the buffer private byte[] buffer; // Small buffer holding converted data private int bufferLength; // Length of buffer (3 or 4) private int numSigBytes; // Number of meaningful bytes in the buffer private int lineLength; private boolean breakLines; // Break lines at less than 80 characters /** * Constructs a {@link Base64.InputStream} in DECODE mode. * * @param in the <tt>java.io.InputStream</tt> from which to read data. * @since 1.3 */ public InputStream(java.io.InputStream in) { this(in, DECODE); } // end constructor /** * Constructs a {@link Base64.InputStream} in either ENCODE or DECODE mode. * <p> * Valid options: * * <pre> * ENCODE or DECODE: Encode or Decode as data is read. * DONT_BREAK_LINES: don't break lines at 76 characters * (only meaningful when encoding) * <i>Note: Technically, this makes your encoding non-compliant.</i> * </pre> * <p> * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code> * * @param in the <tt>java.io.InputStream</tt> from which to read data. * @param options Specified options * @see Base64#ENCODE * @see Base64#DECODE * @see Base64#DONT_BREAK_LINES * @since 2.0 */ public InputStream(java.io.InputStream in, int options) { super(in); this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & ENCODE) == ENCODE; this.bufferLength = encode ? 4 : 3; this.buffer = new byte[bufferLength]; this.position = -1; this.lineLength = 0; } // end constructor /** * Reads enough of the input stream to convert to/from Base64 and returns the next byte. * * @return next byte * @since 1.3 */ public int read() throws java.io.IOException { // Do we need to get data? if (position < 0) { if (encode) { byte[] b3 = new byte[3]; int numBinaryBytes = 0; for (int i = 0; i < 3; i++) { try { int b = in.read(); // If end of stream, b is -1. if (b >= 0) { b3[i] = (byte) b; numBinaryBytes++; } // end if: not end of stream } // end try: read catch (java.io.IOException e) { // Only a problem if we got no data at all. if (i == 0) throw e; } // end catch } // end for: each needed input byte if (numBinaryBytes > 0) { encode3to4(b3, 0, numBinaryBytes, buffer, 0); position = 0; numSigBytes = 4; } // end if: got data else { return -1; } // end else } // end if: encoding // Else decoding else { byte[] b4 = new byte[4]; int i = 0; for (i = 0; i < 4; i++) { // Read four "meaningful" bytes: int b = 0; do { b = in.read(); } while (b >= 0 && DECODABET[b & 0x7f] <= WHITE_SPACE_ENC); if (b < 0) break; // Reads a -1 if end of stream b4[i] = (byte) b; } // end for: each needed input byte if (i == 4) { numSigBytes = decode4to3(b4, 0, buffer, 0); position = 0; } // end if: got four characters else if (i == 0) { return -1; } // end else if: also padded correctly else { // Must have broken out from above. throw new java.io.IOException("Improperly padded Base64 input."); } // end } // end else: decode } // end else: get data // Got data? if (position >= 0) { // End of relevant data? if (/* !encode && */position >= numSigBytes) return -1; if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) { lineLength = 0; return '\n'; } // end if else { lineLength++; // This isn't important when decoding // but throwing an extra "if" seems // just as wasteful. int b = buffer[position++]; if (position >= bufferLength) position = -1; return b & 0xFF; // This is how you "cast" a byte that's // intended to be unsigned. } // end else } // end if: position >= 0 // Else error else { // When JDK1.4 is more accepted, use an assertion here. throw new java.io.IOException("Error in Base64 code reading stream."); } // end else } // end read /** * Calls {@link #read()} repeatedly until the end of stream is reached or <var>len</var> bytes are read. Returns * number of bytes read into array or -1 if end of stream is encountered. * * @param dest array to hold values * @param off offset for array * @param len max number of bytes to read into array * @return bytes read into array or -1 if end of stream is encountered. * @since 1.3 */ public int read(byte[] dest, int off, int len) throws java.io.IOException { int i; int b; for (i = 0; i < len; i++) { b = read(); // if( b < 0 && i == 0 ) // return -1; if (b >= 0) dest[off + i] = (byte) b; else if (i == 0) return -1; else break; // Out of 'for' loop } // end for: each byte read return i; } // end read } // end inner class InputStream /* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */ /** * A {@link Base64.OutputStream} will write data to another <tt>java.io.OutputStream</tt>, given in the constructor, * and encode/decode to/from Base64 notation on the fly. * * @see Base64 * @since 1.3 */ public static class OutputStream extends java.io.FilterOutputStream { private boolean encode; private int position; private byte[] buffer; private int bufferLength; private int lineLength; private boolean breakLines; private byte[] b4; // Scratch used in a few places private boolean suspendEncoding; /** * Constructs a {@link Base64.OutputStream} in ENCODE mode. * * @param out the <tt>java.io.OutputStream</tt> to which data will be written. * @since 1.3 */ public OutputStream(java.io.OutputStream out) { this(out, ENCODE); } // end constructor /** * Constructs a {@link Base64.OutputStream} in either ENCODE or DECODE mode. * <p> * Valid options: * * <pre> * ENCODE or DECODE: Encode or Decode as data is read. * DONT_BREAK_LINES: don't break lines at 76 characters * (only meaningful when encoding) * <i>Note: Technically, this makes your encoding non-compliant.</i> * </pre> * <p> * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code> * * @param out the <tt>java.io.OutputStream</tt> to which data will be written. * @param options Specified options. * @see Base64#ENCODE * @see Base64#DECODE * @see Base64#DONT_BREAK_LINES * @since 1.3 */ public OutputStream(java.io.OutputStream out, int options) { super(out); this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & ENCODE) == ENCODE; this.bufferLength = encode ? 3 : 4; this.buffer = new byte[bufferLength]; this.position = 0; this.lineLength = 0; this.suspendEncoding = false; this.b4 = new byte[4]; } // end constructor /** * Writes the byte to the output stream after converting to/from Base64 notation. When encoding, bytes are * buffered three at a time before the output stream actually gets a write() call. When decoding, bytes are * buffered four at a time. * * @param theByte the byte to write * @since 1.3 */ public void write(int theByte) throws java.io.IOException { // Encoding suspended? if (suspendEncoding) { super.out.write(theByte); return; } // end if: supsended // Encode? if (encode) { buffer[position++] = (byte) theByte; if (position >= bufferLength) // Enough to encode. { out.write(encode3to4(b4, buffer, bufferLength)); lineLength += 4; if (breakLines && lineLength >= MAX_LINE_LENGTH) { out.write(NEW_LINE); lineLength = 0; } // end if: end of line position = 0; } // end if: enough to output } // end if: encoding // Else, Decoding else { // Meaningful Base64 character? if (DECODABET[theByte & 0x7f] > WHITE_SPACE_ENC) { buffer[position++] = (byte) theByte; if (position >= bufferLength) // Enough to output. { int len = Base64.decode4to3(buffer, 0, b4, 0); out.write(b4, 0, len); // out.write( Base64.decode4to3( buffer ) ); position = 0; } // end if: enough to output } // end if: meaningful base64 character else if (DECODABET[theByte & 0x7f] != WHITE_SPACE_ENC) { throw new java.io.IOException("Invalid character in Base64 data."); } // end else: not white space either } // end else: decoding } // end write /** * Calls {@link #write(int)} repeatedly until <var>len</var> bytes are written. * * @param theBytes array from which to read bytes * @param off offset for array * @param len max number of bytes to read into array * @since 1.3 */ public void write(byte[] theBytes, int off, int len) throws java.io.IOException { // Encoding suspended? if (suspendEncoding) { super.out.write(theBytes, off, len); return; } // end if: supsended for (int i = 0; i < len; i++) { write(theBytes[off + i]); } // end for: each byte written } // end write /** * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer without closing the stream. */ public void flushBase64() throws java.io.IOException { if (position > 0) { if (encode) { out.write(encode3to4(b4, buffer, position)); position = 0; } // end if: encoding else { throw new java.io.IOException("Base64 input not properly padded."); } // end else: decoding } // end if: buffer partially full } // end flush /** * Flushes and closes (I think, in the superclass) the stream. * * @since 1.3 */ public void close() throws java.io.IOException { // 1. Ensure that pending characters are written flushBase64(); // 2. Actually close the stream // Base class both flushes and closes. super.close(); buffer = null; out = null; } // end close /** * Suspends encoding of the stream. May be helpful if you need to embed a piece of base640-encoded data in a * stream. * * @since 1.5.1 */ public void suspendEncoding() throws java.io.IOException { flushBase64(); this.suspendEncoding = true; } // end suspendEncoding /** * Resumes encoding of the stream. May be helpful if you need to embed a piece of base640-encoded data in a * stream. * * @since 1.5.1 */ public void resumeEncoding() { this.suspendEncoding = false; } // end resumeEncoding } // end inner class OutputStream } // end class Base64