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8187443: Forest Consolidation: Move files to unified layout
Reviewed-by: darcy, ihse
This commit is contained in:
Erik Joelsson
parent
270fe13182
commit
3789983e89
56923 changed files with 3 additions and 15727 deletions
603
src/java.base/share/classes/java/io/DataInput.java
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603
src/java.base/share/classes/java/io/DataInput.java
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@ -0,0 +1,603 @@
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/*
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* Copyright (c) 1995, 2017, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
|
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* published by the Free Software Foundation. Oracle designates this
|
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
|
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*
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||||
* This code 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
|
||||
* version 2 for more details (a copy is included in the LICENSE file that
|
||||
* accompanied this code).
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License version
|
||||
* 2 along with this work; if not, write to the Free Software Foundation,
|
||||
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
|
||||
*
|
||||
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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||||
* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package java.io;
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/**
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* The {@code DataInput} interface provides
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* for reading bytes from a binary stream and
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* reconstructing from them data in any of
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* the Java primitive types. There is also
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* a
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* facility for reconstructing a {@code String}
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* from data in
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* <a href="#modified-utf-8">modified UTF-8</a>
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* format.
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* <p>
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* It is generally true of all the reading
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* routines in this interface that if end of
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* file is reached before the desired number
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* of bytes has been read, an {@code EOFException}
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* (which is a kind of {@code IOException})
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* is thrown. If any byte cannot be read for
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* any reason other than end of file, an {@code IOException}
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* other than {@code EOFException} is
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* thrown. In particular, an {@code IOException}
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* may be thrown if the input stream has been
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* closed.
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*
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* <h3><a id="modified-utf-8">Modified UTF-8</a></h3>
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* <p>
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* Implementations of the DataInput and DataOutput interfaces represent
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* Unicode strings in a format that is a slight modification of UTF-8.
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* (For information regarding the standard UTF-8 format, see section
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* <i>3.9 Unicode Encoding Forms</i> of <i>The Unicode Standard, Version
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* 4.0</i>)
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*
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* <ul>
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* <li>Characters in the range {@code '\u005Cu0001'} to
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* {@code '\u005Cu007F'} are represented by a single byte.
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* <li>The null character {@code '\u005Cu0000'} and characters
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* in the range {@code '\u005Cu0080'} to {@code '\u005Cu07FF'} are
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* represented by a pair of bytes.
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* <li>Characters in the range {@code '\u005Cu0800'}
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* to {@code '\u005CuFFFF'} are represented by three bytes.
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* </ul>
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*
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* <table class="plain" style="margin-left:2em;">
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* <caption>Encoding of UTF-8 values</caption>
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* <thead>
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* <tr>
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* <th scope="col" rowspan="2">Value</th>
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* <th scope="col" rowspan="2">Byte</th>
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* <th scope="col" colspan="8" id="bit_a">Bit Values</th>
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* </tr>
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* <tr>
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* <!-- Value -->
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* <!-- Byte -->
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* <th scope="col" style="width:3em"> 7 </th>
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* <th scope="col" style="width:3em"> 6 </th>
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* <th scope="col" style="width:3em"> 5 </th>
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* <th scope="col" style="width:3em"> 4 </th>
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* <th scope="col" style="width:3em"> 3 </th>
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* <th scope="col" style="width:3em"> 2 </th>
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* <th scope="col" style="width:3em"> 1 </th>
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* <th scope="col" style="width:3em"> 0 </th>
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* </thead>
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* <tbody>
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* <tr>
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* <th scope="row" style="text-align:left; font-weight:normal">
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* {@code \u005Cu0001} to {@code \u005Cu007F} </th>
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* <th scope="row" style="font-weight:normal; text-align:center"> 1 </th>
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* <td style="text-align:center">0
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* <td colspan="7" style="text-align:right; padding-right:6em">bits 6-0
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* </tr>
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* <tr>
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* <th scope="row" rowspan="2" style="text-align:left; font-weight:normal">
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* {@code \u005Cu0000},<br>
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* {@code \u005Cu0080} to {@code \u005Cu07FF} </th>
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* <th scope="row" style="font-weight:normal; text-align:center"> 1 </th>
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* <td style="text-align:center">1
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* <td style="text-align:center">1
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* <td style="text-align:center">0
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* <td colspan="5" style="text-align:right; padding-right:6em">bits 10-6
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* </tr>
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* <tr>
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* <!-- (value) -->
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* <th scope="row" style="font-weight:normal; text-align:center"> 2 </th>
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* <td style="text-align:center">1
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* <td style="text-align:center">0
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* <td colspan="6" style="text-align:right; padding-right:6em">bits 5-0
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* </tr>
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* <tr>
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* <th scope="row" rowspan="3" style="text-align:left; font-weight:normal">
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* {@code \u005Cu0800} to {@code \u005CuFFFF} </th>
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* <th scope="row" style="font-weight:normal; text-align:center"> 1 </th>
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* <td style="text-align:center">1
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* <td style="text-align:center">1
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* <td style="text-align:center">1
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* <td style="text-align:center">0
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* <td colspan="4" style="text-align:right; padding-right:6em">bits 15-12
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* </tr>
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* <tr>
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* <!-- (value) -->
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* <th scope="row" style="font-weight:normal; text-align:center"> 2 </th>
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* <td style="text-align:center">1
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* <td style="text-align:center">0
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* <td colspan="6" style="text-align:right; padding-right:6em">bits 11-6
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* </tr>
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* <tr>
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* <!-- (value) -->
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* <th scope="row" style="font-weight:normal; text-align:center"> 3 </th>
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* <td style="text-align:center">1
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* <td style="text-align:center">0
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* <td colspan="6" style="text-align:right; padding-right:6em">bits 5-0
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* </tr>
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* </tbody>
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* </table>
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*
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* <p>
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* The differences between this format and the
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* standard UTF-8 format are the following:
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* <ul>
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* <li>The null byte {@code '\u005Cu0000'} is encoded in 2-byte format
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* rather than 1-byte, so that the encoded strings never have
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* embedded nulls.
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* <li>Only the 1-byte, 2-byte, and 3-byte formats are used.
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* <li><a href="../lang/Character.html#unicode">Supplementary characters</a>
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* are represented in the form of surrogate pairs.
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* </ul>
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* @author Frank Yellin
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* @see java.io.DataInputStream
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* @see java.io.DataOutput
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* @since 1.0
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*/
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public
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interface DataInput {
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/**
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* Reads some bytes from an input
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* stream and stores them into the buffer
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* array {@code b}. The number of bytes
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* read is equal
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* to the length of {@code b}.
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* <p>
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* This method blocks until one of the
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* following conditions occurs:
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* <ul>
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* <li>{@code b.length}
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* bytes of input data are available, in which
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* case a normal return is made.
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*
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* <li>End of
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* file is detected, in which case an {@code EOFException}
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* is thrown.
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*
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* <li>An I/O error occurs, in
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* which case an {@code IOException} other
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* than {@code EOFException} is thrown.
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* </ul>
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* <p>
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* If {@code b} is {@code null},
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* a {@code NullPointerException} is thrown.
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* If {@code b.length} is zero, then
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* no bytes are read. Otherwise, the first
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* byte read is stored into element {@code b[0]},
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* the next one into {@code b[1]}, and
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* so on.
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* If an exception is thrown from
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* this method, then it may be that some but
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* not all bytes of {@code b} have been
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* updated with data from the input stream.
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*
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* @param b the buffer into which the data is read.
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* @throws NullPointerException if {@code b} is {@code null}.
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* @throws EOFException if this stream reaches the end before reading
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* all the bytes.
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* @throws IOException if an I/O error occurs.
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*/
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void readFully(byte b[]) throws IOException;
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/**
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*
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* Reads {@code len}
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* bytes from
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* an input stream.
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* <p>
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* This method
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* blocks until one of the following conditions
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* occurs:
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* <ul>
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* <li>{@code len} bytes
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* of input data are available, in which case
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* a normal return is made.
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*
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* <li>End of file
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* is detected, in which case an {@code EOFException}
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* is thrown.
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*
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* <li>An I/O error occurs, in
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* which case an {@code IOException} other
|
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* than {@code EOFException} is thrown.
|
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* </ul>
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* <p>
|
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* If {@code b} is {@code null},
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* a {@code NullPointerException} is thrown.
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* If {@code off} is negative, or {@code len}
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* is negative, or {@code off+len} is
|
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* greater than the length of the array {@code b},
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* then an {@code IndexOutOfBoundsException}
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* is thrown.
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* If {@code len} is zero,
|
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* then no bytes are read. Otherwise, the first
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* byte read is stored into element {@code b[off]},
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* the next one into {@code b[off+1]},
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* and so on. The number of bytes read is,
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* at most, equal to {@code len}.
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*
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* @param b the buffer into which the data is read.
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* @param off an int specifying the offset in the data array {@code b}.
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* @param len an int specifying the number of bytes to read.
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* @throws NullPointerException if {@code b} is {@code null}.
|
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* @throws IndexOutOfBoundsException if {@code off} is negative,
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* {@code len} is negative, or {@code len} is greater than
|
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* {@code b.length - off}.
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* @throws EOFException if this stream reaches the end before reading
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* all the bytes.
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* @throws IOException if an I/O error occurs.
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*/
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void readFully(byte b[], int off, int len) throws IOException;
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/**
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* Makes an attempt to skip over
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* {@code n} bytes
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* of data from the input
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* stream, discarding the skipped bytes. However,
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* it may skip
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* over some smaller number of
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* bytes, possibly zero. This may result from
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* any of a
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* number of conditions; reaching
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* end of file before {@code n} bytes
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* have been skipped is
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* only one possibility.
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* This method never throws an {@code EOFException}.
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* The actual
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* number of bytes skipped is returned.
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*
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* @param n the number of bytes to be skipped.
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* @return the number of bytes actually skipped.
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* @exception IOException if an I/O error occurs.
|
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*/
|
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int skipBytes(int n) throws IOException;
|
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|
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/**
|
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* Reads one input byte and returns
|
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* {@code true} if that byte is nonzero,
|
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* {@code false} if that byte is zero.
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* This method is suitable for reading
|
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* the byte written by the {@code writeBoolean}
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* method of interface {@code DataOutput}.
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*
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* @return the {@code boolean} value read.
|
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* @exception EOFException if this stream reaches the end before reading
|
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* all the bytes.
|
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* @exception IOException if an I/O error occurs.
|
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*/
|
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boolean readBoolean() throws IOException;
|
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|
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/**
|
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* Reads and returns one input byte.
|
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* The byte is treated as a signed value in
|
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* the range {@code -128} through {@code 127},
|
||||
* inclusive.
|
||||
* This method is suitable for
|
||||
* reading the byte written by the {@code writeByte}
|
||||
* method of interface {@code DataOutput}.
|
||||
*
|
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* @return the 8-bit value read.
|
||||
* @exception EOFException if this stream reaches the end before reading
|
||||
* all the bytes.
|
||||
* @exception IOException if an I/O error occurs.
|
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*/
|
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byte readByte() throws IOException;
|
||||
|
||||
/**
|
||||
* Reads one input byte, zero-extends
|
||||
* it to type {@code int}, and returns
|
||||
* the result, which is therefore in the range
|
||||
* {@code 0}
|
||||
* through {@code 255}.
|
||||
* This method is suitable for reading
|
||||
* the byte written by the {@code writeByte}
|
||||
* method of interface {@code DataOutput}
|
||||
* if the argument to {@code writeByte}
|
||||
* was intended to be a value in the range
|
||||
* {@code 0} through {@code 255}.
|
||||
*
|
||||
* @return the unsigned 8-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 readUnsignedByte() throws IOException;
|
||||
|
||||
/**
|
||||
* Reads two input bytes and returns
|
||||
* a {@code short} value. Let {@code a}
|
||||
* be the first byte read and {@code b}
|
||||
* be the second byte. The value
|
||||
* returned
|
||||
* is:
|
||||
* <pre>{@code (short)((a << 8) | (b & 0xff))
|
||||
* }</pre>
|
||||
* This method
|
||||
* is suitable for reading the bytes written
|
||||
* by the {@code writeShort} method of
|
||||
* interface {@code DataOutput}.
|
||||
*
|
||||
* @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} value in the range {@code 0}
|
||||
* through {@code 65535}. Let {@code a}
|
||||
* be the first byte read and
|
||||
* {@code b}
|
||||
* be the second byte. The value returned is:
|
||||
* <pre>{@code (((a & 0xff) << 8) | (b & 0xff))
|
||||
* }</pre>
|
||||
* This method is suitable for reading the bytes
|
||||
* written by the {@code writeShort} method
|
||||
* of interface {@code DataOutput} if
|
||||
* the argument to {@code writeShort}
|
||||
* was intended to be a value in the range
|
||||
* {@code 0} through {@code 65535}.
|
||||
*
|
||||
* @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 two input bytes and returns a {@code char} value.
|
||||
* Let {@code a}
|
||||
* be the first byte read and {@code b}
|
||||
* be the second byte. The value
|
||||
* returned is:
|
||||
* <pre>{@code (char)((a << 8) | (b & 0xff))
|
||||
* }</pre>
|
||||
* This method
|
||||
* is suitable for reading bytes written by
|
||||
* the {@code writeChar} method of interface
|
||||
* {@code DataOutput}.
|
||||
*
|
||||
* @return the {@code char} value 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} value. Let {@code a-d}
|
||||
* be the first through fourth bytes read. The value returned is:
|
||||
* <pre>{@code
|
||||
* (((a & 0xff) << 24) | ((b & 0xff) << 16) |
|
||||
* ((c & 0xff) << 8) | (d & 0xff))
|
||||
* }</pre>
|
||||
* This method is suitable
|
||||
* for reading bytes written by the {@code writeInt}
|
||||
* method of interface {@code DataOutput}.
|
||||
*
|
||||
* @return the {@code int} 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} value. Let {@code a-h}
|
||||
* be the first through eighth bytes read.
|
||||
* The value returned is:
|
||||
* <pre>{@code
|
||||
* (((long)(a & 0xff) << 56) |
|
||||
* ((long)(b & 0xff) << 48) |
|
||||
* ((long)(c & 0xff) << 40) |
|
||||
* ((long)(d & 0xff) << 32) |
|
||||
* ((long)(e & 0xff) << 24) |
|
||||
* ((long)(f & 0xff) << 16) |
|
||||
* ((long)(g & 0xff) << 8) |
|
||||
* ((long)(h & 0xff)))
|
||||
* }</pre>
|
||||
* <p>
|
||||
* This method is suitable
|
||||
* for reading bytes written by the {@code writeLong}
|
||||
* method of interface {@code DataOutput}.
|
||||
*
|
||||
* @return the {@code long} 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 four input bytes and returns
|
||||
* a {@code float} value. It does this
|
||||
* by first constructing an {@code int}
|
||||
* value in exactly the manner
|
||||
* of the {@code readInt}
|
||||
* method, then converting this {@code int}
|
||||
* value to a {@code float} in
|
||||
* exactly the manner of the method {@code Float.intBitsToFloat}.
|
||||
* This method is suitable for reading
|
||||
* bytes written by the {@code writeFloat}
|
||||
* method of interface {@code DataOutput}.
|
||||
*
|
||||
* @return the {@code float} value read.
|
||||
* @exception EOFException if this stream reaches the end before reading
|
||||
* all the bytes.
|
||||
* @exception IOException if an I/O error occurs.
|
||||
*/
|
||||
float readFloat() throws IOException;
|
||||
|
||||
/**
|
||||
* Reads eight input bytes and returns
|
||||
* a {@code double} value. It does this
|
||||
* by first constructing a {@code long}
|
||||
* value in exactly the manner
|
||||
* of the {@code readLong}
|
||||
* method, then converting this {@code long}
|
||||
* value to a {@code double} in exactly
|
||||
* the manner of the method {@code Double.longBitsToDouble}.
|
||||
* This method is suitable for reading
|
||||
* bytes written by the {@code writeDouble}
|
||||
* method of interface {@code DataOutput}.
|
||||
*
|
||||
* @return the {@code double} value read.
|
||||
* @exception EOFException if this stream reaches the end before reading
|
||||
* all the bytes.
|
||||
* @exception IOException if an I/O error occurs.
|
||||
*/
|
||||
double readDouble() throws IOException;
|
||||
|
||||
/**
|
||||
* Reads the next line of text from the input stream.
|
||||
* It reads successive bytes, converting
|
||||
* each byte separately into a character,
|
||||
* until it encounters a line terminator or
|
||||
* end of
|
||||
* file; the characters read are then
|
||||
* returned as a {@code String}. Note
|
||||
* that because this
|
||||
* method processes bytes,
|
||||
* it does not support input of the full Unicode
|
||||
* character set.
|
||||
* <p>
|
||||
* If end of file is encountered
|
||||
* before even one byte can be read, then {@code null}
|
||||
* is returned. Otherwise, each byte that is
|
||||
* read is converted to type {@code char}
|
||||
* by zero-extension. If the character {@code '\n'}
|
||||
* is encountered, it is discarded and reading
|
||||
* ceases. If the character {@code '\r'}
|
||||
* is encountered, it is discarded and, if
|
||||
* the following byte converts  to the
|
||||
* character {@code '\n'}, then that is
|
||||
* discarded also; reading then ceases. If
|
||||
* end of file is encountered before either
|
||||
* of the characters {@code '\n'} and
|
||||
* {@code '\r'} is encountered, reading
|
||||
* ceases. Once reading has ceased, a {@code String}
|
||||
* is returned that contains all the characters
|
||||
* read and not discarded, taken in order.
|
||||
* Note that every character in this string
|
||||
* will have a value less than {@code \u005Cu0100},
|
||||
* that is, {@code (char)256}.
|
||||
*
|
||||
* @return the next line of text from the input stream,
|
||||
* or {@code null} if the end of file is
|
||||
* encountered before a byte can be read.
|
||||
* @exception IOException if an I/O error occurs.
|
||||
*/
|
||||
String readLine() throws IOException;
|
||||
|
||||
/**
|
||||
* Reads in a string that has been encoded using a
|
||||
* <a href="#modified-utf-8">modified UTF-8</a>
|
||||
* format.
|
||||
* The general contract of {@code readUTF}
|
||||
* is that it reads a representation of a Unicode
|
||||
* character string encoded in modified
|
||||
* UTF-8 format; this string of characters
|
||||
* is then returned as a {@code String}.
|
||||
* <p>
|
||||
* First, two bytes are read and used to
|
||||
* construct an unsigned 16-bit integer in
|
||||
* exactly the manner of the {@code readUnsignedShort}
|
||||
* 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}
|
||||
* (where {@code x} means "may be {@code 0}
|
||||
* or {@code 1}"), 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},
|
||||
* then the group consists of that byte {@code a}
|
||||
* and a second byte {@code b}. If there
|
||||
* is no byte {@code b} (because byte
|
||||
* {@code a} was the last of the bytes
|
||||
* to be read), or if byte {@code b} does
|
||||
* not match the bit pattern {@code 10xxxxxx},
|
||||
* then a {@code UTFDataFormatException}
|
||||
* is thrown. Otherwise, the group is converted
|
||||
* to the character:
|
||||
* <pre>{@code (char)(((a & 0x1F) << 6) | (b & 0x3F))
|
||||
* }</pre>
|
||||
* If the first byte of a group
|
||||
* matches the bit pattern {@code 1110xxxx},
|
||||
* then the group consists of that byte {@code a}
|
||||
* and two more bytes {@code b} and {@code c}.
|
||||
* If there is no byte {@code c} (because
|
||||
* byte {@code a} was one of the last
|
||||
* two of the bytes to be read), or either
|
||||
* byte {@code b} or byte {@code c}
|
||||
* does not match the bit pattern {@code 10xxxxxx},
|
||||
* then a {@code UTFDataFormatException}
|
||||
* is thrown. Otherwise, the group is converted
|
||||
* to the character:
|
||||
* <pre>{@code
|
||||
* (char)(((a & 0x0F) << 12) | ((b & 0x3F) << 6) | (c & 0x3F))
|
||||
* }</pre>
|
||||
* If the first byte of a group matches the
|
||||
* pattern {@code 1111xxxx} or the pattern
|
||||
* {@code 10xxxxxx}, then a {@code UTFDataFormatException}
|
||||
* is thrown.
|
||||
* <p>
|
||||
* If end of file is encountered
|
||||
* at any time during this entire process,
|
||||
* then an {@code EOFException} 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},
|
||||
* which is returned.
|
||||
* <p>
|
||||
* The {@code writeUTF}
|
||||
* method of interface {@code DataOutput}
|
||||
* 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 modified UTF-8 encoding of a string.
|
||||
*/
|
||||
String readUTF() throws IOException;
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue