Java 日看一类（10）之IO包中的DataInput接口

DataInput接口没有引入的包或继承的类；

接口注释如下：

/**
 * The {@code DataInput} interface provides
 * for reading bytes from a binary stream and
 * reconstructing from them data in any of
 * the Java primitive types. There is also
 * a
 * facility for reconstructing a {@code String}
 * from data in
 * <a href="#modified-utf-8">modified UTF-8</a>
 * format.
 * <p>
 * It is generally true of all the reading
 * routines in this interface that if end of
 * file is reached before the desired number
 * of bytes has been read, an {@code EOFException}
 * (which is a kind of {@code IOException})
 * is thrown. If any byte cannot be read for
 * any reason other than end of file, an {@code IOException}
 * other than {@code EOFException} is
 * thrown. In particular, an {@code IOException}
 * may be thrown if the input stream has been
 * closed.
 *
 * <h3><a name="modified-utf-8">Modified UTF-8</a></h3>
 * <p>
 * Implementations of the DataInput and DataOutput interfaces represent
 * Unicode strings in a format that is a slight modification of UTF-8.
 * (For information regarding the standard UTF-8 format, see section
 * <i>3.9 Unicode Encoding Forms</i> of <i>The Unicode Standard, Version
 * 4.0</i>).
 * Note that in the following table, the most significant bit appears in the
 * far left-hand column.
 *
 * <blockquote>
 *   <table border="1" cellspacing="0" cellpadding="8"
 *          summary="Bit values and bytes">
 *     <tr>
 *       <th colspan="9"><span style="font-weight:normal">
 *         All characters in the range {@code '\u005Cu0001'} to
 *         {@code '\u005Cu007F'} are represented by a single byte:</span></th>
 *     </tr>
 *     <tr>
 *       <td></td>
 *       <th colspan="8" id="bit_a">Bit Values</th>
 *     </tr>
 *     <tr>
 *       <th id="byte1_a">Byte 1</th>
 *       <td><center>0</center>
 *       <td colspan="7"><center>bits 6-0</center>
 *     </tr>
 *     <tr>
 *       <th colspan="9"><span style="font-weight:normal">
 *         The null character {@code '\u005Cu0000'} and characters
 *         in the range {@code '\u005Cu0080'} to {@code '\u005Cu07FF'} are
 *         represented by a pair of bytes:</span></th>
 *     </tr>
 *     <tr>
 *       <td></td>
 *       <th colspan="8" id="bit_b">Bit Values</th>
 *     </tr>
 *     <tr>
 *       <th id="byte1_b">Byte 1</th>
 *       <td><center>1</center>
 *       <td><center>1</center>
 *       <td><center>0</center>
 *       <td colspan="5"><center>bits 10-6</center>
 *     </tr>
 *     <tr>
 *       <th id="byte2_a">Byte 2</th>
 *       <td><center>1</center>
 *       <td><center>0</center>
 *       <td colspan="6"><center>bits 5-0</center>
 *     </tr>
 *     <tr>
 *       <th colspan="9"><span style="font-weight:normal">
 *         {@code char} values in the range {@code '\u005Cu0800'}
 *         to {@code '\u005CuFFFF'} are represented by three bytes:</span></th>
 *     </tr>
 *     <tr>
 *       <td></td>
 *       <th colspan="8"id="bit_c">Bit Values</th>
 *     </tr>
 *     <tr>
 *       <th id="byte1_c">Byte 1</th>
 *       <td><center>1</center>
 *       <td><center>1</center>
 *       <td><center>1</center>
 *       <td><center>0</center>
 *       <td colspan="4"><center>bits 15-12</center>
 *     </tr>
 *     <tr>
 *       <th id="byte2_b">Byte 2</th>
 *       <td><center>1</center>
 *       <td><center>0</center>
 *       <td colspan="6"><center>bits 11-6</center>
 *     </tr>
 *     <tr>
 *       <th id="byte3">Byte 3</th>
 *       <td><center>1</center>
 *       <td><center>0</center>
 *       <td colspan="6"><center>bits 5-0</center>
 *     </tr>
 *   </table>
 * </blockquote>
 * <p>
 * The differences between this format and the
 * standard UTF-8 format are the following:
 * <ul>
 * <li>The null byte {@code '\u005Cu0000'} is encoded in 2-byte format
 *     rather than 1-byte, so that the encoded strings never have
 *     embedded nulls.
 * <li>Only the 1-byte, 2-byte, and 3-byte formats are used.
 * <li><a href="../lang/Character.html#unicode">Supplementary characters</a>
 *     are represented in the form of surrogate pairs.
 * </ul>
 * @author  Frank Yellin
 * @see     java.io.DataInputStream
 * @see     java.io.DataOutput
 * @since   JDK1.0
 */