datainput.java

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     * is:
     * <p><pre><code>(short)((a &lt;&lt; 8) * | (b &amp; 0xff))
     * </code></pre>
     * This method
     * is suitable for reading the bytes written
     * by the <code>writeShort</code> method of
     * interface <code>DataOutput</code>.
     *
     * @return     the 16-bit value read.
     * @exception  EOFException  if this stream reaches the end before reading
     *             all the bytes.
     * @exception  IOException   if an I/O error occurs.
     */
    short readShort() throws IOException;

    /**
     * Reads two input bytes and returns
     * an <code>int</code> value in the range <code>0</code>
     * through <code>65535</code>. Let <code>a</code>
     * be the first byte read and
     * <code>b</code>
     * be the second byte. The value returned is:
     * <p><pre><code>(((a &amp; 0xff) &lt;&lt; 8) | (b &amp; 0xff))
     * </code></pre>
     * This method is suitable for reading the bytes
     * written by the <code>writeShort</code> method
     * of interface <code>DataOutput</code>  if
     * the argument to <code>writeShort</code>
     * was intended to be a value in the range
     * <code>0</code> through <code>65535</code>.
     *
     * @return     the unsigned 16-bit value read.
     * @exception  EOFException  if this stream reaches the end before reading
     *             all the bytes.
     * @exception  IOException   if an I/O error occurs.
     */
    int readUnsignedShort() throws IOException;

    /**
     * Reads an input <code>char</code> and returns the <code>char</code> value.
     * A Unicode <code>char</code> is made up of two bytes.
     * Let <code>a</code>
     * be the first byte read and <code>b</code>
     * be the second byte. The value
     * returned is:
     * <p><pre><code>(char)((a &lt;&lt; 8) | (b &amp; 0xff))
     * </code></pre>
     * This method
     * is suitable for reading bytes written by
     * the <code>writeChar</code> method of interface
     * <code>DataOutput</code>.
     *
     * @return     the Unicode <code>char</code> read.
     * @exception  EOFException  if this stream reaches the end before reading
     *             all the bytes.
     * @exception  IOException   if an I/O error occurs.
     */
    char readChar() throws IOException;

    /**
     * Reads four input bytes and returns an
     * <code>int</code> value. Let <code>a</code>
     * be the first byte read, <code>b</code> be
     * the second byte, <code>c</code> be the third
     * byte,
     * and <code>d</code> be the fourth
     * byte. The value returned is:
     * <p><pre>
     * <code>
     * (((a &amp; 0xff) &lt;&lt; 24) | ((b &amp; 0xff) &lt;&lt; 16) |
     * &#32;((c &amp; 0xff) &lt;&lt; 8) | (d &amp; 0xff))
     * </code></pre>
     * This method is suitable
     * for reading bytes written by the <code>writeInt</code>
     * method of interface <code>DataOutput</code>.
     *
     * @return     the <code>int</code> value read.
     * @exception  EOFException  if this stream reaches the end before reading
     *             all the bytes.
     * @exception  IOException   if an I/O error occurs.
     */
    int readInt() throws IOException;

    /**
     * Reads eight input bytes and returns
     * a <code>long</code> value. Let <code>a</code>
     * be the first byte read, <code>b</code> be
     * the second byte, <code>c</code> be the third
     * byte, <code>d</code>
     * be the fourth byte,
     * <code>e</code> be the fifth byte, <code>f</code>
     * be the sixth byte, <code>g</code> be the
     * seventh byte,
     * and <code>h</code> be the
     * eighth byte. The value returned is:
     * <p><pre> <code>
     * (((long)(a &amp; 0xff) &lt;&lt; 56) |
     *  ((long)(b &amp; 0xff) &lt;&lt; 48) |
     *  ((long)(c &amp; 0xff) &lt;&lt; 40) |
     *  ((long)(d &amp; 0xff) &lt;&lt; 32) |
     *  ((long)(e &amp; 0xff) &lt;&lt; 24) |
     *  ((long)(f &amp; 0xff) &lt;&lt; 16) |
     *  ((long)(g &amp; 0xff) &lt;&lt;  8) |
     *  ((long)(h &amp; 0xff)))
     * </code></pre>
     * <p>
     * This method is suitable
     * for reading bytes written by the <code>writeLong</code>
     * method of interface <code>DataOutput</code>.
     *
     * @return     the <code>long</code> value read.
     * @exception  EOFException  if this stream reaches the end before reading
     *             all the bytes.
     * @exception  IOException   if an I/O error occurs.
     */
    long readLong() throws IOException;

    /**
     * Reads in a string that has been encoded using a modified UTF-8 format.
     * The general contract of <code>readUTF</code>
     * is that it reads a representation of a Unicode
     * character string encoded in Java modified
     * UTF-8 format; this string of characters
     * is then returned as a <code>String</code>.
     * <p>
     * First, two bytes are read and used to
     * construct an unsigned 16-bit integer in
     * exactly the manner of the <code>readUnsignedShort</code>
     * method . This integer value is called the
     * <i>UTF length</i> and specifies the number
     * of additional bytes to be read. These bytes
     * are then converted to characters by considering
     * them in groups. The length of each group
     * is computed from the value of the first
     * byte of the group. The byte following a
     * group, if any, is the first byte of the
     * next group.
     * <p>
     * If the first byte of a group
     * matches the bit pattern <code>0xxxxxxx</code>
     * (where <code>x</code> means "may be <code>0</code>
     * or <code>1</code>"), then the group consists
     * of just that byte. The byte is zero-extended
     * to form a character.
     * <p>
     * If the first byte
     * of a group matches the bit pattern <code>110xxxxx</code>,
     * then the group consists of that byte <code>a</code>
     * and a second byte <code>b</code>. If there
     * is no byte <code>b</code> (because byte
     * <code>a</code> was the last of the bytes
     * to be read), or if byte <code>b</code> does
     * not match the bit pattern <code>10xxxxxx</code>,
     * then a <code>UTFDataFormatException</code>
     * is thrown. Otherwise, the group is converted
     * to the character:<p>
     * <pre><code>(char)(((a&amp; 0x1F) &lt;&lt; 6) | (b &amp; 0x3F))
     * </code></pre>
     * If the first byte of a group
     * matches the bit pattern <code>1110xxxx</code>,
     * then the group consists of that byte <code>a</code>
     * and two more bytes <code>b</code> and <code>c</code>.
     * If there is no byte <code>c</code> (because
     * byte <code>a</code> was one of the last
     * two of the bytes to be read), or either
     * byte <code>b</code> or byte <code>c</code>
     * does not match the bit pattern <code>10xxxxxx</code>,
     * then a <code>UTFDataFormatException</code>
     * is thrown. Otherwise, the group is converted
     * to the character:<p>
     * <pre><code>
     * (char)(((a &amp; 0x0F) &lt;&lt; 12) | ((b &amp; 0x3F) &lt;&lt; 6) | (c &amp; 0x3F))
     * </code></pre>
     * If the first byte of a group matches the
     * pattern <code>1111xxxx</code> or the pattern
     * <code>10xxxxxx</code>, then a <code>UTFDataFormatException</code>
     * is thrown.
     * <p>
     * If end of file is encountered
     * at any time during this entire process,
     * then an <code>EOFException</code> is thrown.
     * <p>
     * After every group has been converted to
     * a character by this process, the characters
     * are gathered, in the same order in which
     * their corresponding groups were read from
     * the input stream, to form a <code>String</code>,
     * which is returned.
     * <p>
     * The <code>writeUTF</code>
     * method of interface <code>DataOutput</code>
     * may be used to write data that is suitable
     * for reading by this method.
     * @return     a Unicode string.
     * @exception  EOFException            if this stream reaches the end
     *             before reading all the bytes.
     * @exception  IOException             if an I/O error occurs.
     * @exception  UTFDataFormatException  if the bytes do not represent a
     *             valid UTF-8 encoding of a string.
     */
    String readUTF() throws IOException;

}