diff options
Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/java/io/Base64InputStream.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/java/io/Base64InputStream.java | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/java/io/Base64InputStream.java b/gcc-4.4.3/libjava/classpath/gnu/java/io/Base64InputStream.java new file mode 100644 index 000000000..1f5d220db --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/java/io/Base64InputStream.java @@ -0,0 +1,220 @@ +/* Base64InputStream.java -- base-64 input stream. + Copyright (C) 2003, 2004 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package gnu.java.io; + +import java.io.ByteArrayInputStream; +import java.io.ByteArrayOutputStream; +import java.io.FilterInputStream; +import java.io.IOException; +import java.io.InputStream; + +/** + * A filter input stream that decodes data encoded in the Base-64 + * encoding scheme. + * + * @author Casey Marshall (rsdio@metastatic.org) + */ +public class Base64InputStream extends FilterInputStream +{ + + // Constants and fields. + // ------------------------------------------------------------------------ + + /** Base-64 digits. */ + private static final String BASE_64 = + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + + /** Base-64 padding character. */ + private static final char BASE_64_PAD = '='; + + /** Decoding state. */ + private int state; + + /** Intermediate decoded value. */ + private int temp; + + /** EOF flag. */ + private boolean eof; + + private final byte[] one = new byte[1]; + + // Constructors. + // ------------------------------------------------------------------------ + + /** + * Create a new Base-64 input stream. The input bytes must be the + * ASCII characters A-Z, a-z, 0-9, + and /, with optional whitespace, + * and will be decoded into a byte stream. + * + * @param in The source of Base-64 input. + */ + public Base64InputStream(InputStream in) + { + super(in); + state = 0; + temp = 0; + eof = false; + } + + // Class method. + // ------------------------------------------------------------------------ + + /** + * Decode a single Base-64 string to a byte array. + * + * @param base64 The Base-64 encoded data. + * @return The decoded bytes. + * @throws IOException If the given data do not compose a valid Base-64 + * sequence. + */ + public static byte[] decode(String base64) throws IOException + { + Base64InputStream in = + new Base64InputStream(new ByteArrayInputStream(base64.getBytes())); + ByteArrayOutputStream out = + new ByteArrayOutputStream((int) (base64.length() / 0.666)); + byte[] buf = new byte[1024]; + int len; + while ((len = in.read(buf)) != -1) + out.write(buf, 0, len); + return out.toByteArray(); + } + + // Instance methods. + // ------------------------------------------------------------------------ + + public int available() + { + return 0; + } + + public int read() throws IOException + { + if (read(one) == 1) + return one[0]; + return -1; + } + + public int read(byte[] buf, int off, int len) throws IOException + { + if (eof) + return -1; + int count = 0; + while (count < len) + { + int i; + while (Character.isWhitespace((char) (i = in.read()))) + ; + + int pos = BASE_64.indexOf((char) i); + if (pos >= 0) + { + switch (state) + { + case 0: + temp = pos << 2; + state = 1; + break; + case 1: + buf[count++] = (byte) (temp | (pos >>> 4)); + temp = (pos & 0x0F) << 4; + state = 2; + break; + case 2: + buf[count++] = (byte) (temp | (pos >>> 2)); + temp = (pos & 0x03) << 6; + state = 3; + break; + case 3: + buf[count++] = (byte) (temp | pos); + state = 0; + break; + } + } + else if (i == BASE_64_PAD) + { + switch (state) + { + case 0: + case 1: + throw new IOException("malformed Base-64 input"); + case 2: + while (Character.isWhitespace((char) (i = in.read()))) + ; + if (i != BASE_64_PAD) + throw new IOException("malformed Base-64 input"); + case 3: + while (Character.isWhitespace((char) (i = in.read()))) + ; + } + eof = true; + break; + } + else // First non-Base-64 character, consider it end-of-stream. + { + if (state != 0) + throw new IOException("malformed Base-64 input"); + eof = true; + break; + } + } + return count; + } + + public boolean markSupported() + { + return false; + } + + public void mark(int markLimit) { } + + public void reset() throws IOException + { + throw new IOException("reset not supported"); + } + + public long skip(long n) throws IOException + { + long skipped; + for (skipped = 0; skipped < n; skipped++) + if (read() == -1) + break; + return skipped; + } +} |