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    1   /*
    2    * Copyright (c) 1994, 2006, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   package java.io;
   27   
   28   /**
   29    * A data input stream lets an application read primitive Java data
   30    * types from an underlying input stream in a machine-independent
   31    * way. An application uses a data output stream to write data that
   32    * can later be read by a data input stream.
   33    * <p>
   34    * DataInputStream is not necessarily safe for multithreaded access.
   35    * Thread safety is optional and is the responsibility of users of
   36    * methods in this class.
   37    *
   38    * @author  Arthur van Hoff
   39    * @see     java.io.DataOutputStream
   40    * @since   JDK1.0
   41    */
   42   public
   43   class DataInputStream extends FilterInputStream implements DataInput {
   44   
   45       /**
   46        * Creates a DataInputStream that uses the specified
   47        * underlying InputStream.
   48        *
   49        * @param  in   the specified input stream
   50        */
   51       public DataInputStream(InputStream in) {
   52           super(in);
   53       }
   54   
   55       /**
   56        * working arrays initialized on demand by readUTF
   57        */
   58       private byte bytearr[] = new byte[80];
   59       private char chararr[] = new char[80];
   60   
   61       /**
   62        * Reads some number of bytes from the contained input stream and
   63        * stores them into the buffer array <code>b</code>. The number of
   64        * bytes actually read is returned as an integer. This method blocks
   65        * until input data is available, end of file is detected, or an
   66        * exception is thrown.
   67        *
   68        * <p>If <code>b</code> is null, a <code>NullPointerException</code> is
   69        * thrown. If the length of <code>b</code> is zero, then no bytes are
   70        * read and <code>0</code> is returned; otherwise, there is an attempt
   71        * to read at least one byte. If no byte is available because the
   72        * stream is at end of file, the value <code>-1</code> is returned;
   73        * otherwise, at least one byte is read and stored into <code>b</code>.
   74        *
   75        * <p>The first byte read is stored into element <code>b[0]</code>, the
   76        * next one into <code>b[1]</code>, and so on. The number of bytes read
   77        * is, at most, equal to the length of <code>b</code>. Let <code>k</code>
   78        * be the number of bytes actually read; these bytes will be stored in
   79        * elements <code>b[0]</code> through <code>b[k-1]</code>, leaving
   80        * elements <code>b[k]</code> through <code>b[b.length-1]</code>
   81        * unaffected.
   82        *
   83        * <p>The <code>read(b)</code> method has the same effect as:
   84        * <blockquote><pre>
   85        * read(b, 0, b.length)
   86        * </pre></blockquote>
   87        *
   88        * @param      b   the buffer into which the data is read.
   89        * @return     the total number of bytes read into the buffer, or
   90        *             <code>-1</code> if there is no more data because the end
   91        *             of the stream has been reached.
   92        * @exception  IOException if the first byte cannot be read for any reason
   93        * other than end of file, the stream has been closed and the underlying
   94        * input stream does not support reading after close, or another I/O
   95        * error occurs.
   96        * @see        java.io.FilterInputStream#in
   97        * @see        java.io.InputStream#read(byte[], int, int)
   98        */
   99       public final int read(byte b[]) throws IOException {
  100           return in.read(b, 0, b.length);
  101       }
  102   
  103       /**
  104        * Reads up to <code>len</code> bytes of data from the contained
  105        * input stream into an array of bytes.  An attempt is made to read
  106        * as many as <code>len</code> bytes, but a smaller number may be read,
  107        * possibly zero. The number of bytes actually read is returned as an
  108        * integer.
  109        *
  110        * <p> This method blocks until input data is available, end of file is
  111        * detected, or an exception is thrown.
  112        *
  113        * <p> If <code>len</code> is zero, then no bytes are read and
  114        * <code>0</code> is returned; otherwise, there is an attempt to read at
  115        * least one byte. If no byte is available because the stream is at end of
  116        * file, the value <code>-1</code> is returned; otherwise, at least one
  117        * byte is read and stored into <code>b</code>.
  118        *
  119        * <p> The first byte read is stored into element <code>b[off]</code>, the
  120        * next one into <code>b[off+1]</code>, and so on. The number of bytes read
  121        * is, at most, equal to <code>len</code>. Let <i>k</i> be the number of
  122        * bytes actually read; these bytes will be stored in elements
  123        * <code>b[off]</code> through <code>b[off+</code><i>k</i><code>-1]</code>,
  124        * leaving elements <code>b[off+</code><i>k</i><code>]</code> through
  125        * <code>b[off+len-1]</code> unaffected.
  126        *
  127        * <p> In every case, elements <code>b[0]</code> through
  128        * <code>b[off]</code> and elements <code>b[off+len]</code> through
  129        * <code>b[b.length-1]</code> are unaffected.
  130        *
  131        * @param      b     the buffer into which the data is read.
  132        * @param off the start offset in the destination array <code>b</code>
  133        * @param      len   the maximum number of bytes read.
  134        * @return     the total number of bytes read into the buffer, or
  135        *             <code>-1</code> if there is no more data because the end
  136        *             of the stream has been reached.
  137        * @exception  NullPointerException If <code>b</code> is <code>null</code>.
  138        * @exception  IndexOutOfBoundsException If <code>off</code> is negative,
  139        * <code>len</code> is negative, or <code>len</code> is greater than
  140        * <code>b.length - off</code>
  141        * @exception  IOException if the first byte cannot be read for any reason
  142        * other than end of file, the stream has been closed and the underlying
  143        * input stream does not support reading after close, or another I/O
  144        * error occurs.
  145        * @see        java.io.FilterInputStream#in
  146        * @see        java.io.InputStream#read(byte[], int, int)
  147        */
  148       public final int read(byte b[], int off, int len) throws IOException {
  149           return in.read(b, off, len);
  150       }
  151   
  152       /**
  153        * See the general contract of the <code>readFully</code>
  154        * method of <code>DataInput</code>.
  155        * <p>
  156        * Bytes
  157        * for this operation are read from the contained
  158        * input stream.
  159        *
  160        * @param      b   the buffer into which the data is read.
  161        * @exception  EOFException  if this input stream reaches the end before
  162        *             reading all the bytes.
  163        * @exception  IOException   the stream has been closed and the contained
  164        *             input stream does not support reading after close, or
  165        *             another I/O error occurs.
  166        * @see        java.io.FilterInputStream#in
  167        */
  168       public final void readFully(byte b[]) throws IOException {
  169           readFully(b, 0, b.length);
  170       }
  171   
  172       /**
  173        * See the general contract of the <code>readFully</code>
  174        * method of <code>DataInput</code>.
  175        * <p>
  176        * Bytes
  177        * for this operation are read from the contained
  178        * input stream.
  179        *
  180        * @param      b     the buffer into which the data is read.
  181        * @param      off   the start offset of the data.
  182        * @param      len   the number of bytes to read.
  183        * @exception  EOFException  if this input stream reaches the end before
  184        *               reading all the bytes.
  185        * @exception  IOException   the stream has been closed and the contained
  186        *             input stream does not support reading after close, or
  187        *             another I/O error occurs.
  188        * @see        java.io.FilterInputStream#in
  189        */
  190       public final void readFully(byte b[], int off, int len) throws IOException {
  191           if (len < 0)
  192               throw new IndexOutOfBoundsException();
  193           int n = 0;
  194           while (n < len) {
  195               int count = in.read(b, off + n, len - n);
  196               if (count < 0)
  197                   throw new EOFException();
  198               n += count;
  199           }
  200       }
  201   
  202       /**
  203        * See the general contract of the <code>skipBytes</code>
  204        * method of <code>DataInput</code>.
  205        * <p>
  206        * Bytes for this operation are read from the contained
  207        * input stream.
  208        *
  209        * @param      n   the number of bytes to be skipped.
  210        * @return     the actual number of bytes skipped.
  211        * @exception  IOException  if the contained input stream does not support
  212        *             seek, or the stream has been closed and
  213        *             the contained input stream does not support
  214        *             reading after close, or another I/O error occurs.
  215        */
  216       public final int skipBytes(int n) throws IOException {
  217           int total = 0;
  218           int cur = 0;
  219   
  220           while ((total<n) && ((cur = (int) in.skip(n-total)) > 0)) {
  221               total += cur;
  222           }
  223   
  224           return total;
  225       }
  226   
  227       /**
  228        * See the general contract of the <code>readBoolean</code>
  229        * method of <code>DataInput</code>.
  230        * <p>
  231        * Bytes for this operation are read from the contained
  232        * input stream.
  233        *
  234        * @return     the <code>boolean</code> value read.
  235        * @exception  EOFException  if this input stream has reached the end.
  236        * @exception  IOException   the stream has been closed and the contained
  237        *             input stream does not support reading after close, or
  238        *             another I/O error occurs.
  239        * @see        java.io.FilterInputStream#in
  240        */
  241       public final boolean readBoolean() throws IOException {
  242           int ch = in.read();
  243           if (ch < 0)
  244               throw new EOFException();
  245           return (ch != 0);
  246       }
  247   
  248       /**
  249        * See the general contract of the <code>readByte</code>
  250        * method of <code>DataInput</code>.
  251        * <p>
  252        * Bytes
  253        * for this operation are read from the contained
  254        * input stream.
  255        *
  256        * @return     the next byte of this input stream as a signed 8-bit
  257        *             <code>byte</code>.
  258        * @exception  EOFException  if this input stream has reached the end.
  259        * @exception  IOException   the stream has been closed and the contained
  260        *             input stream does not support reading after close, or
  261        *             another I/O error occurs.
  262        * @see        java.io.FilterInputStream#in
  263        */
  264       public final byte readByte() throws IOException {
  265           int ch = in.read();
  266           if (ch < 0)
  267               throw new EOFException();
  268           return (byte)(ch);
  269       }
  270   
  271       /**
  272        * See the general contract of the <code>readUnsignedByte</code>
  273        * method of <code>DataInput</code>.
  274        * <p>
  275        * Bytes
  276        * for this operation are read from the contained
  277        * input stream.
  278        *
  279        * @return     the next byte of this input stream, interpreted as an
  280        *             unsigned 8-bit number.
  281        * @exception  EOFException  if this input stream has reached the end.
  282        * @exception  IOException   the stream has been closed and the contained
  283        *             input stream does not support reading after close, or
  284        *             another I/O error occurs.
  285        * @see         java.io.FilterInputStream#in
  286        */
  287       public final int readUnsignedByte() throws IOException {
  288           int ch = in.read();
  289           if (ch < 0)
  290               throw new EOFException();
  291           return ch;
  292       }
  293   
  294       /**
  295        * See the general contract of the <code>readShort</code>
  296        * method of <code>DataInput</code>.
  297        * <p>
  298        * Bytes
  299        * for this operation are read from the contained
  300        * input stream.
  301        *
  302        * @return     the next two bytes of this input stream, interpreted as a
  303        *             signed 16-bit number.
  304        * @exception  EOFException  if this input stream reaches the end before
  305        *               reading two bytes.
  306        * @exception  IOException   the stream has been closed and the contained
  307        *             input stream does not support reading after close, or
  308        *             another I/O error occurs.
  309        * @see        java.io.FilterInputStream#in
  310        */
  311       public final short readShort() throws IOException {
  312           int ch1 = in.read();
  313           int ch2 = in.read();
  314           if ((ch1 | ch2) < 0)
  315               throw new EOFException();
  316           return (short)((ch1 << 8) + (ch2 << 0));
  317       }
  318   
  319       /**
  320        * See the general contract of the <code>readUnsignedShort</code>
  321        * method of <code>DataInput</code>.
  322        * <p>
  323        * Bytes
  324        * for this operation are read from the contained
  325        * input stream.
  326        *
  327        * @return     the next two bytes of this input stream, interpreted as an
  328        *             unsigned 16-bit integer.
  329        * @exception  EOFException  if this input stream reaches the end before
  330        *             reading two bytes.
  331        * @exception  IOException   the stream has been closed and the contained
  332        *             input stream does not support reading after close, or
  333        *             another I/O error occurs.
  334        * @see        java.io.FilterInputStream#in
  335        */
  336       public final int readUnsignedShort() throws IOException {
  337           int ch1 = in.read();
  338           int ch2 = in.read();
  339           if ((ch1 | ch2) < 0)
  340               throw new EOFException();
  341           return (ch1 << 8) + (ch2 << 0);
  342       }
  343   
  344       /**
  345        * See the general contract of the <code>readChar</code>
  346        * method of <code>DataInput</code>.
  347        * <p>
  348        * Bytes
  349        * for this operation are read from the contained
  350        * input stream.
  351        *
  352        * @return     the next two bytes of this input stream, interpreted as a
  353        *             <code>char</code>.
  354        * @exception  EOFException  if this input stream reaches the end before
  355        *               reading two bytes.
  356        * @exception  IOException   the stream has been closed and the contained
  357        *             input stream does not support reading after close, or
  358        *             another I/O error occurs.
  359        * @see        java.io.FilterInputStream#in
  360        */
  361       public final char readChar() throws IOException {
  362           int ch1 = in.read();
  363           int ch2 = in.read();
  364           if ((ch1 | ch2) < 0)
  365               throw new EOFException();
  366           return (char)((ch1 << 8) + (ch2 << 0));
  367       }
  368   
  369       /**
  370        * See the general contract of the <code>readInt</code>
  371        * method of <code>DataInput</code>.
  372        * <p>
  373        * Bytes
  374        * for this operation are read from the contained
  375        * input stream.
  376        *
  377        * @return     the next four bytes of this input stream, interpreted as an
  378        *             <code>int</code>.
  379        * @exception  EOFException  if this input stream reaches the end before
  380        *               reading four bytes.
  381        * @exception  IOException   the stream has been closed and the contained
  382        *             input stream does not support reading after close, or
  383        *             another I/O error occurs.
  384        * @see        java.io.FilterInputStream#in
  385        */
  386       public final int readInt() throws IOException {
  387           int ch1 = in.read();
  388           int ch2 = in.read();
  389           int ch3 = in.read();
  390           int ch4 = in.read();
  391           if ((ch1 | ch2 | ch3 | ch4) < 0)
  392               throw new EOFException();
  393           return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
  394       }
  395   
  396       private byte readBuffer[] = new byte[8];
  397   
  398       /**
  399        * See the general contract of the <code>readLong</code>
  400        * method of <code>DataInput</code>.
  401        * <p>
  402        * Bytes
  403        * for this operation are read from the contained
  404        * input stream.
  405        *
  406        * @return     the next eight bytes of this input stream, interpreted as a
  407        *             <code>long</code>.
  408        * @exception  EOFException  if this input stream reaches the end before
  409        *               reading eight bytes.
  410        * @exception  IOException   the stream has been closed and the contained
  411        *             input stream does not support reading after close, or
  412        *             another I/O error occurs.
  413        * @see        java.io.FilterInputStream#in
  414        */
  415       public final long readLong() throws IOException {
  416           readFully(readBuffer, 0, 8);
  417           return (((long)readBuffer[0] << 56) +
  418                   ((long)(readBuffer[1] & 255) << 48) +
  419                   ((long)(readBuffer[2] & 255) << 40) +
  420                   ((long)(readBuffer[3] & 255) << 32) +
  421                   ((long)(readBuffer[4] & 255) << 24) +
  422                   ((readBuffer[5] & 255) << 16) +
  423                   ((readBuffer[6] & 255) <<  8) +
  424                   ((readBuffer[7] & 255) <<  0));
  425       }
  426   
  427       /**
  428        * See the general contract of the <code>readFloat</code>
  429        * method of <code>DataInput</code>.
  430        * <p>
  431        * Bytes
  432        * for this operation are read from the contained
  433        * input stream.
  434        *
  435        * @return     the next four bytes of this input stream, interpreted as a
  436        *             <code>float</code>.
  437        * @exception  EOFException  if this input stream reaches the end before
  438        *               reading four bytes.
  439        * @exception  IOException   the stream has been closed and the contained
  440        *             input stream does not support reading after close, or
  441        *             another I/O error occurs.
  442        * @see        java.io.DataInputStream#readInt()
  443        * @see        java.lang.Float#intBitsToFloat(int)
  444        */
  445       public final float readFloat() throws IOException {
  446           return Float.intBitsToFloat(readInt());
  447       }
  448   
  449       /**
  450        * See the general contract of the <code>readDouble</code>
  451        * method of <code>DataInput</code>.
  452        * <p>
  453        * Bytes
  454        * for this operation are read from the contained
  455        * input stream.
  456        *
  457        * @return     the next eight bytes of this input stream, interpreted as a
  458        *             <code>double</code>.
  459        * @exception  EOFException  if this input stream reaches the end before
  460        *               reading eight bytes.
  461        * @exception  IOException   the stream has been closed and the contained
  462        *             input stream does not support reading after close, or
  463        *             another I/O error occurs.
  464        * @see        java.io.DataInputStream#readLong()
  465        * @see        java.lang.Double#longBitsToDouble(long)
  466        */
  467       public final double readDouble() throws IOException {
  468           return Double.longBitsToDouble(readLong());
  469       }
  470   
  471       private char lineBuffer[];
  472   
  473       /**
  474        * See the general contract of the <code>readLine</code>
  475        * method of <code>DataInput</code>.
  476        * <p>
  477        * Bytes
  478        * for this operation are read from the contained
  479        * input stream.
  480        *
  481        * @deprecated This method does not properly convert bytes to characters.
  482        * As of JDK&nbsp;1.1, the preferred way to read lines of text is via the
  483        * <code>BufferedReader.readLine()</code> method.  Programs that use the
  484        * <code>DataInputStream</code> class to read lines can be converted to use
  485        * the <code>BufferedReader</code> class by replacing code of the form:
  486        * <blockquote><pre>
  487        *     DataInputStream d =&nbsp;new&nbsp;DataInputStream(in);
  488        * </pre></blockquote>
  489        * with:
  490        * <blockquote><pre>
  491        *     BufferedReader d
  492        *          =&nbsp;new&nbsp;BufferedReader(new&nbsp;InputStreamReader(in));
  493        * </pre></blockquote>
  494        *
  495        * @return     the next line of text from this input stream.
  496        * @exception  IOException  if an I/O error occurs.
  497        * @see        java.io.BufferedReader#readLine()
  498        * @see        java.io.FilterInputStream#in
  499        */
  500       @Deprecated
  501       public final String readLine() throws IOException {
  502           char buf[] = lineBuffer;
  503   
  504           if (buf == null) {
  505               buf = lineBuffer = new char[128];
  506           }
  507   
  508           int room = buf.length;
  509           int offset = 0;
  510           int c;
  511   
  512   loop:   while (true) {
  513               switch (c = in.read()) {
  514                 case -1:
  515                 case '\n':
  516                   break loop;
  517   
  518                 case '\r':
  519                   int c2 = in.read();
  520                   if ((c2 != '\n') && (c2 != -1)) {
  521                       if (!(in instanceof PushbackInputStream)) {
  522                           this.in = new PushbackInputStream(in);
  523                       }
  524                       ((PushbackInputStream)in).unread(c2);
  525                   }
  526                   break loop;
  527   
  528                 default:
  529                   if (--room < 0) {
  530                       buf = new char[offset + 128];
  531                       room = buf.length - offset - 1;
  532                       System.arraycopy(lineBuffer, 0, buf, 0, offset);
  533                       lineBuffer = buf;
  534                   }
  535                   buf[offset++] = (char) c;
  536                   break;
  537               }
  538           }
  539           if ((c == -1) && (offset == 0)) {
  540               return null;
  541           }
  542           return String.copyValueOf(buf, 0, offset);
  543       }
  544   
  545       /**
  546        * See the general contract of the <code>readUTF</code>
  547        * method of <code>DataInput</code>.
  548        * <p>
  549        * Bytes
  550        * for this operation are read from the contained
  551        * input stream.
  552        *
  553        * @return     a Unicode string.
  554        * @exception  EOFException  if this input stream reaches the end before
  555        *               reading all the bytes.
  556        * @exception  IOException   the stream has been closed and the contained
  557        *             input stream does not support reading after close, or
  558        *             another I/O error occurs.
  559        * @exception  UTFDataFormatException if the bytes do not represent a valid
  560        *             modified UTF-8 encoding of a string.
  561        * @see        java.io.DataInputStream#readUTF(java.io.DataInput)
  562        */
  563       public final String readUTF() throws IOException {
  564           return readUTF(this);
  565       }
  566   
  567       /**
  568        * Reads from the
  569        * stream <code>in</code> a representation
  570        * of a Unicode  character string encoded in
  571        * <a href="DataInput.html#modified-utf-8">modified UTF-8</a> format;
  572        * this string of characters is then returned as a <code>String</code>.
  573        * The details of the modified UTF-8 representation
  574        * are  exactly the same as for the <code>readUTF</code>
  575        * method of <code>DataInput</code>.
  576        *
  577        * @param      in   a data input stream.
  578        * @return     a Unicode string.
  579        * @exception  EOFException            if the input stream reaches the end
  580        *               before all the bytes.
  581        * @exception  IOException   the stream has been closed and the contained
  582        *             input stream does not support reading after close, or
  583        *             another I/O error occurs.
  584        * @exception  UTFDataFormatException  if the bytes do not represent a
  585        *               valid modified UTF-8 encoding of a Unicode string.
  586        * @see        java.io.DataInputStream#readUnsignedShort()
  587        */
  588       public final static String readUTF(DataInput in) throws IOException {
  589           int utflen = in.readUnsignedShort();
  590           byte[] bytearr = null;
  591           char[] chararr = null;
  592           if (in instanceof DataInputStream) {
  593               DataInputStream dis = (DataInputStream)in;
  594               if (dis.bytearr.length < utflen){
  595                   dis.bytearr = new byte[utflen*2];
  596                   dis.chararr = new char[utflen*2];
  597               }
  598               chararr = dis.chararr;
  599               bytearr = dis.bytearr;
  600           } else {
  601               bytearr = new byte[utflen];
  602               chararr = new char[utflen];
  603           }
  604   
  605           int c, char2, char3;
  606           int count = 0;
  607           int chararr_count=0;
  608   
  609           in.readFully(bytearr, 0, utflen);
  610   
  611           while (count < utflen) {
  612               c = (int) bytearr[count] & 0xff;
  613               if (c > 127) break;
  614               count++;
  615               chararr[chararr_count++]=(char)c;
  616           }
  617   
  618           while (count < utflen) {
  619               c = (int) bytearr[count] & 0xff;
  620               switch (c >> 4) {
  621                   case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
  622                       /* 0xxxxxxx*/
  623                       count++;
  624                       chararr[chararr_count++]=(char)c;
  625                       break;
  626                   case 12: case 13:
  627                       /* 110x xxxx   10xx xxxx*/
  628                       count += 2;
  629                       if (count > utflen)
  630                           throw new UTFDataFormatException(
  631                               "malformed input: partial character at end");
  632                       char2 = (int) bytearr[count-1];
  633                       if ((char2 & 0xC0) != 0x80)
  634                           throw new UTFDataFormatException(
  635                               "malformed input around byte " + count);
  636                       chararr[chararr_count++]=(char)(((c & 0x1F) << 6) |
  637                                                       (char2 & 0x3F));
  638                       break;
  639                   case 14:
  640                       /* 1110 xxxx  10xx xxxx  10xx xxxx */
  641                       count += 3;
  642                       if (count > utflen)
  643                           throw new UTFDataFormatException(
  644                               "malformed input: partial character at end");
  645                       char2 = (int) bytearr[count-2];
  646                       char3 = (int) bytearr[count-1];
  647                       if (((char2 & 0xC0) != 0x80) || ((char3 & 0xC0) != 0x80))
  648                           throw new UTFDataFormatException(
  649                               "malformed input around byte " + (count-1));
  650                       chararr[chararr_count++]=(char)(((c     & 0x0F) << 12) |
  651                                                       ((char2 & 0x3F) << 6)  |
  652                                                       ((char3 & 0x3F) << 0));
  653                       break;
  654                   default:
  655                       /* 10xx xxxx,  1111 xxxx */
  656                       throw new UTFDataFormatException(
  657                           "malformed input around byte " + count);
  658               }
  659           }
  660           // The number of chars produced may be less than utflen
  661           return new String(chararr, 0, chararr_count);
  662       }
  663   }

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