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/*
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* Copyright 1994-2007 Sun Microsystems, Inc. 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. Sun designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Sun 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
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*/
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package java.io;
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import java.nio.channels.FileChannel;
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import sun.nio.ch.FileChannelImpl;
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/**
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* Instances of this class support both reading and writing to a
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* random access file. A random access file behaves like a large
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* array of bytes stored in the file system. There is a kind of cursor,
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* or index into the implied array, called the <em>file pointer</em>;
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* input operations read bytes starting at the file pointer and advance
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* the file pointer past the bytes read. If the random access file is
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* created in read/write mode, then output operations are also available;
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* output operations write bytes starting at the file pointer and advance
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* the file pointer past the bytes written. Output operations that write
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* past the current end of the implied array cause the array to be
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* extended. The file pointer can be read by the
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* <code>getFilePointer</code> method and set by the <code>seek</code>
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* method.
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* <p>
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* It is generally true of all the reading routines in this class that
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* if end-of-file is reached before the desired number of bytes has been
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* read, an <code>EOFException</code> (which is a kind of
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* <code>IOException</code>) is thrown. If any byte cannot be read for
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* any reason other than end-of-file, an <code>IOException</code> other
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* than <code>EOFException</code> is thrown. In particular, an
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* <code>IOException</code> may be thrown if the stream has been closed.
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*
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* @author unascribed
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* @since JDK1.0
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*/
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public class RandomAccessFile implements DataOutput, DataInput, Closeable {
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private FileDescriptor fd;
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private FileChannel channel = null;
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private boolean rw;
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private Object closeLock = new Object();
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private volatile boolean closed = false;
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private static final int O_RDONLY = 1;
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private static final int O_RDWR = 2;
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private static final int O_SYNC = 4;
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private static final int O_DSYNC = 8;
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/**
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* Creates a random access file stream to read from, and optionally
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* to write to, a file with the specified name. A new
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* {@link FileDescriptor} object is created to represent the
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* connection to the file.
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*
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* <p> The <tt>mode</tt> argument specifies the access mode with which the
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* file is to be opened. The permitted values and their meanings are as
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* specified for the <a
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* href="#mode"><tt>RandomAccessFile(File,String)</tt></a> constructor.
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*
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* <p>
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* If there is a security manager, its <code>checkRead</code> method
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* is called with the <code>name</code> argument
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* as its argument to see if read access to the file is allowed.
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* If the mode allows writing, the security manager's
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* <code>checkWrite</code> method
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* is also called with the <code>name</code> argument
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* as its argument to see if write access to the file is allowed.
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*
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* @param name the system-dependent filename
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* @param mode the access <a href="#mode">mode</a>
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* @exception IllegalArgumentException if the mode argument is not equal
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* to one of <tt>"r"</tt>, <tt>"rw"</tt>, <tt>"rws"</tt>, or
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* <tt>"rwd"</tt>
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* @exception FileNotFoundException
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* if the mode is <tt>"r"</tt> but the given string does not
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* denote an existing regular file, or if the mode begins with
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* <tt>"rw"</tt> but the given string does not denote an
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* existing, writable regular file and a new regular file of
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* that name cannot be created, or if some other error occurs
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* while opening or creating the file
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* @exception SecurityException if a security manager exists and its
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* <code>checkRead</code> method denies read access to the file
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* or the mode is "rw" and the security manager's
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* <code>checkWrite</code> method denies write access to the file
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* @see java.lang.SecurityException
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* @see java.lang.SecurityManager#checkRead(java.lang.String)
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* @see java.lang.SecurityManager#checkWrite(java.lang.String)
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* @revised 1.4
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* @spec JSR-51
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*/
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public RandomAccessFile(String name, String mode)
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throws FileNotFoundException
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{
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this(name != null ? new File(name) : null, mode);
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}
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/**
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* Creates a random access file stream to read from, and optionally to
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* write to, the file specified by the {@link File} argument. A new {@link
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* FileDescriptor} object is created to represent this file connection.
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*
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* <a name="mode"><p> The <tt>mode</tt> argument specifies the access mode
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* in which the file is to be opened. The permitted values and their
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* meanings are:
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*
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* <blockquote><table summary="Access mode permitted values and meanings">
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* <tr><th><p align="left">Value</p></th><th><p align="left">Meaning</p></th></tr>
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* <tr><td valign="top"><tt>"r"</tt></td>
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* <td> Open for reading only. Invoking any of the <tt>write</tt>
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* methods of the resulting object will cause an {@link
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* java.io.IOException} to be thrown. </td></tr>
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* <tr><td valign="top"><tt>"rw"</tt></td>
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* <td> Open for reading and writing. If the file does not already
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* exist then an attempt will be made to create it. </td></tr>
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* <tr><td valign="top"><tt>"rws"</tt></td>
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* <td> Open for reading and writing, as with <tt>"rw"</tt>, and also
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* require that every update to the file's content or metadata be
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* written synchronously to the underlying storage device. </td></tr>
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* <tr><td valign="top"><tt>"rwd" </tt></td>
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* <td> Open for reading and writing, as with <tt>"rw"</tt>, and also
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* require that every update to the file's content be written
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* synchronously to the underlying storage device. </td></tr>
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* </table></blockquote>
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*
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* The <tt>"rws"</tt> and <tt>"rwd"</tt> modes work much like the {@link
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* java.nio.channels.FileChannel#force(boolean) force(boolean)} method of
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* the {@link java.nio.channels.FileChannel} class, passing arguments of
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* <tt>true</tt> and <tt>false</tt>, respectively, except that they always
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* apply to every I/O operation and are therefore often more efficient. If
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* the file resides on a local storage device then when an invocation of a
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* method of this class returns it is guaranteed that all changes made to
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* the file by that invocation will have been written to that device. This
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* is useful for ensuring that critical information is not lost in the
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* event of a system crash. If the file does not reside on a local device
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* then no such guarantee is made.
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*
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* <p> The <tt>"rwd"</tt> mode can be used to reduce the number of I/O
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* operations performed. Using <tt>"rwd"</tt> only requires updates to the
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* file's content to be written to storage; using <tt>"rws"</tt> requires
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* updates to both the file's content and its metadata to be written, which
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* generally requires at least one more low-level I/O operation.
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*
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* <p> If there is a security manager, its <code>checkRead</code> method is
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* called with the pathname of the <code>file</code> argument as its
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* argument to see if read access to the file is allowed. If the mode
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* allows writing, the security manager's <code>checkWrite</code> method is
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* also called with the path argument to see if write access to the file is
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* allowed.
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*
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* @param file the file object
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* @param mode the access mode, as described
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* <a href="#mode">above</a>
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* @exception IllegalArgumentException if the mode argument is not equal
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* to one of <tt>"r"</tt>, <tt>"rw"</tt>, <tt>"rws"</tt>, or
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* <tt>"rwd"</tt>
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* @exception FileNotFoundException
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* if the mode is <tt>"r"</tt> but the given file object does
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* not denote an existing regular file, or if the mode begins
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* with <tt>"rw"</tt> but the given file object does not denote
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* an existing, writable regular file and a new regular file of
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* that name cannot be created, or if some other error occurs
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* while opening or creating the file
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* @exception SecurityException if a security manager exists and its
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* <code>checkRead</code> method denies read access to the file
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* or the mode is "rw" and the security manager's
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* <code>checkWrite</code> method denies write access to the file
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* @see java.lang.SecurityManager#checkRead(java.lang.String)
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* @see java.lang.SecurityManager#checkWrite(java.lang.String)
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* @see java.nio.channels.FileChannel#force(boolean)
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* @revised 1.4
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* @spec JSR-51
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*/
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public RandomAccessFile(File file, String mode)
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throws FileNotFoundException
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{
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String name = (file != null ? file.getPath() : null);
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int imode = -1;
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if (mode.equals("r"))
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imode = O_RDONLY;
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else if (mode.startsWith("rw")) {
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imode = O_RDWR;
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rw = true;
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if (mode.length() > 2) {
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if (mode.equals("rws"))
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imode |= O_SYNC;
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else if (mode.equals("rwd"))
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imode |= O_DSYNC;
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else
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imode = -1;
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}
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}
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if (imode < 0)
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throw new IllegalArgumentException("Illegal mode \"" + mode
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+ "\" must be one of "
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+ "\"r\", \"rw\", \"rws\","
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+ " or \"rwd\"");
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SecurityManager security = System.getSecurityManager();
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if (security != null) {
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security.checkRead(name);
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if (rw) {
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security.checkWrite(name);
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}
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}
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if (name == null) {
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throw new NullPointerException();
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}
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fd = new FileDescriptor();
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fd.incrementAndGetUseCount();
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open(name, imode);
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}
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/**
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* Returns the opaque file descriptor object associated with this
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* stream. </p>
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*
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* @return the file descriptor object associated with this stream.
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* @exception IOException if an I/O error occurs.
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* @see java.io.FileDescriptor
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*/
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public final FileDescriptor getFD() throws IOException {
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if (fd != null) return fd;
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throw new IOException();
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}
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/**
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* Returns the unique {@link java.nio.channels.FileChannel FileChannel}
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* object associated with this file.
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*
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* <p> The {@link java.nio.channels.FileChannel#position()
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* </code>position<code>} of the returned channel will always be equal to
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* this object's file-pointer offset as returned by the {@link
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* #getFilePointer getFilePointer} method. Changing this object's
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* file-pointer offset, whether explicitly or by reading or writing bytes,
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* will change the position of the channel, and vice versa. Changing the
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* file's length via this object will change the length seen via the file
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* channel, and vice versa.
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*
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* @return the file channel associated with this file
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*
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* @since 1.4
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* @spec JSR-51
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*/
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public final FileChannel getChannel() {
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synchronized (this) {
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if (channel == null) {
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channel = FileChannelImpl.open(fd, true, rw, this);
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/*
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* FileDescriptor could be shared by FileInputStream or
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* FileOutputStream.
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* Ensure that FD is GC'ed only when all the streams/channels
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* are done using it.
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* Increment fd's use count. Invoking the channel's close()
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* method will result in decrementing the use count set for
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* the channel.
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*/
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fd.incrementAndGetUseCount();
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}
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return channel;
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}
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}
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/**
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* Opens a file and returns the file descriptor. The file is
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* opened in read-write mode if the O_RDWR bit in <code>mode</code>
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* is true, else the file is opened as read-only.
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* If the <code>name</code> refers to a directory, an IOException
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* is thrown.
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*
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* @param name the name of the file
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* @param mode the mode flags, a combination of the O_ constants
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* defined above
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*/
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private native void open(String name, int mode)
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throws FileNotFoundException;
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// 'Read' primitives
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/**
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* Reads a byte of data from this file. The byte is returned as an
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* integer in the range 0 to 255 (<code>0x00-0x0ff</code>). This
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* method blocks if no input is yet available.
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* <p>
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* Although <code>RandomAccessFile</code> is not a subclass of
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* <code>InputStream</code>, this method behaves in exactly the same
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* way as the {@link InputStream#read()} method of
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* <code>InputStream</code>.
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*
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* @return the next byte of data, or <code>-1</code> if the end of the
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* file has been reached.
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* @exception IOException if an I/O error occurs. Not thrown if
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* end-of-file has been reached.
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*/
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public native int read() throws IOException;
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/**
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* Reads a sub array as a sequence of bytes.
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* @param b the buffer into which the data is read.
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* @param off the start offset of the data.
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* @param len the number of bytes to read.
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* @exception IOException If an I/O error has occurred.
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*/
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private native int readBytes(byte b[], int off, int len) throws IOException;
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/**
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* Reads up to <code>len</code> bytes of data from this file into an
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* array of bytes. This method blocks until at least one byte of input
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* is available.
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* <p>
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* Although <code>RandomAccessFile</code> is not a subclass of
|
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* <code>InputStream</code>, this method behaves in exactly the
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* same way as the {@link InputStream#read(byte[], int, int)} method of
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* <code>InputStream</code>.
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*
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* @param b the buffer into which the data is read.
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* @param off the start offset in array <code>b</code>
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* at which the data is written.
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* @param len the maximum number of bytes read.
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* @return the total number of bytes read into the buffer, or
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* <code>-1</code> if there is no more data because the end of
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* the file has been reached.
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* @exception IOException If the first byte cannot be read for any reason
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* other than end of file, or if the random access file has been closed, or if
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* some other I/O error occurs.
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* @exception NullPointerException If <code>b</code> is <code>null</code>.
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* @exception IndexOutOfBoundsException If <code>off</code> is negative,
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* <code>len</code> is negative, or <code>len</code> is greater than
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* <code>b.length - off</code>
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*/
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public int read(byte b[], int off, int len) throws IOException {
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return readBytes(b, off, len);
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}
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/**
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* Reads up to <code>b.length</code> bytes of data from this file
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* into an array of bytes. This method blocks until at least one byte
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* of input is available.
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* <p>
|
|
363 |
* Although <code>RandomAccessFile</code> is not a subclass of
|
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364 |
* <code>InputStream</code>, this method behaves in exactly the
|
|
365 |
* same way as the {@link InputStream#read(byte[])} method of
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* <code>InputStream</code>.
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*
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* @param b the buffer into which the data is read.
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* @return the total number of bytes read into the buffer, or
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* <code>-1</code> if there is no more data because the end of
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* this file has been reached.
|
|
372 |
* @exception IOException If the first byte cannot be read for any reason
|
|
373 |
* other than end of file, or if the random access file has been closed, or if
|
|
374 |
* some other I/O error occurs.
|
|
375 |
* @exception NullPointerException If <code>b</code> is <code>null</code>.
|
|
376 |
*/
|
|
377 |
public int read(byte b[]) throws IOException {
|
|
378 |
return readBytes(b, 0, b.length);
|
|
379 |
}
|
|
380 |
|
|
381 |
/**
|
|
382 |
* Reads <code>b.length</code> bytes from this file into the byte
|
|
383 |
* array, starting at the current file pointer. This method reads
|
|
384 |
* repeatedly from the file until the requested number of bytes are
|
|
385 |
* read. This method blocks until the requested number of bytes are
|
|
386 |
* read, the end of the stream is detected, or an exception is thrown.
|
|
387 |
*
|
|
388 |
* @param b the buffer into which the data is read.
|
|
389 |
* @exception EOFException if this file reaches the end before reading
|
|
390 |
* all the bytes.
|
|
391 |
* @exception IOException if an I/O error occurs.
|
|
392 |
*/
|
|
393 |
public final void readFully(byte b[]) throws IOException {
|
|
394 |
readFully(b, 0, b.length);
|
|
395 |
}
|
|
396 |
|
|
397 |
/**
|
|
398 |
* Reads exactly <code>len</code> bytes from this file into the byte
|
|
399 |
* array, starting at the current file pointer. This method reads
|
|
400 |
* repeatedly from the file until the requested number of bytes are
|
|
401 |
* read. This method blocks until the requested number of bytes are
|
|
402 |
* read, the end of the stream is detected, or an exception is thrown.
|
|
403 |
*
|
|
404 |
* @param b the buffer into which the data is read.
|
|
405 |
* @param off the start offset of the data.
|
|
406 |
* @param len the number of bytes to read.
|
|
407 |
* @exception EOFException if this file reaches the end before reading
|
|
408 |
* all the bytes.
|
|
409 |
* @exception IOException if an I/O error occurs.
|
|
410 |
*/
|
|
411 |
public final void readFully(byte b[], int off, int len) throws IOException {
|
|
412 |
int n = 0;
|
|
413 |
do {
|
|
414 |
int count = this.read(b, off + n, len - n);
|
|
415 |
if (count < 0)
|
|
416 |
throw new EOFException();
|
|
417 |
n += count;
|
|
418 |
} while (n < len);
|
|
419 |
}
|
|
420 |
|
|
421 |
/**
|
|
422 |
* Attempts to skip over <code>n</code> bytes of input discarding the
|
|
423 |
* skipped bytes.
|
|
424 |
* <p>
|
|
425 |
*
|
|
426 |
* This method may skip over some smaller number of bytes, possibly zero.
|
|
427 |
* This may result from any of a number of conditions; reaching end of
|
|
428 |
* file before <code>n</code> bytes have been skipped is only one
|
|
429 |
* possibility. This method never throws an <code>EOFException</code>.
|
|
430 |
* The actual number of bytes skipped is returned. If <code>n</code>
|
|
431 |
* is negative, no bytes are skipped.
|
|
432 |
*
|
|
433 |
* @param n the number of bytes to be skipped.
|
|
434 |
* @return the actual number of bytes skipped.
|
|
435 |
* @exception IOException if an I/O error occurs.
|
|
436 |
*/
|
|
437 |
public int skipBytes(int n) throws IOException {
|
|
438 |
long pos;
|
|
439 |
long len;
|
|
440 |
long newpos;
|
|
441 |
|
|
442 |
if (n <= 0) {
|
|
443 |
return 0;
|
|
444 |
}
|
|
445 |
pos = getFilePointer();
|
|
446 |
len = length();
|
|
447 |
newpos = pos + n;
|
|
448 |
if (newpos > len) {
|
|
449 |
newpos = len;
|
|
450 |
}
|
|
451 |
seek(newpos);
|
|
452 |
|
|
453 |
/* return the actual number of bytes skipped */
|
|
454 |
return (int) (newpos - pos);
|
|
455 |
}
|
|
456 |
|
|
457 |
// 'Write' primitives
|
|
458 |
|
|
459 |
/**
|
|
460 |
* Writes the specified byte to this file. The write starts at
|
|
461 |
* the current file pointer.
|
|
462 |
*
|
|
463 |
* @param b the <code>byte</code> to be written.
|
|
464 |
* @exception IOException if an I/O error occurs.
|
|
465 |
*/
|
|
466 |
public native void write(int b) throws IOException;
|
|
467 |
|
|
468 |
/**
|
|
469 |
* Writes a sub array as a sequence of bytes.
|
|
470 |
* @param b the data to be written
|
|
471 |
|
|
472 |
* @param off the start offset in the data
|
|
473 |
* @param len the number of bytes that are written
|
|
474 |
* @exception IOException If an I/O error has occurred.
|
|
475 |
*/
|
|
476 |
private native void writeBytes(byte b[], int off, int len) throws IOException;
|
|
477 |
|
|
478 |
/**
|
|
479 |
* Writes <code>b.length</code> bytes from the specified byte array
|
|
480 |
* to this file, starting at the current file pointer.
|
|
481 |
*
|
|
482 |
* @param b the data.
|
|
483 |
* @exception IOException if an I/O error occurs.
|
|
484 |
*/
|
|
485 |
public void write(byte b[]) throws IOException {
|
|
486 |
writeBytes(b, 0, b.length);
|
|
487 |
}
|
|
488 |
|
|
489 |
/**
|
|
490 |
* Writes <code>len</code> bytes from the specified byte array
|
|
491 |
* starting at offset <code>off</code> to this file.
|
|
492 |
*
|
|
493 |
* @param b the data.
|
|
494 |
* @param off the start offset in the data.
|
|
495 |
* @param len the number of bytes to write.
|
|
496 |
* @exception IOException if an I/O error occurs.
|
|
497 |
*/
|
|
498 |
public void write(byte b[], int off, int len) throws IOException {
|
|
499 |
writeBytes(b, off, len);
|
|
500 |
}
|
|
501 |
|
|
502 |
// 'Random access' stuff
|
|
503 |
|
|
504 |
/**
|
|
505 |
* Returns the current offset in this file.
|
|
506 |
*
|
|
507 |
* @return the offset from the beginning of the file, in bytes,
|
|
508 |
* at which the next read or write occurs.
|
|
509 |
* @exception IOException if an I/O error occurs.
|
|
510 |
*/
|
|
511 |
public native long getFilePointer() throws IOException;
|
|
512 |
|
|
513 |
/**
|
|
514 |
* Sets the file-pointer offset, measured from the beginning of this
|
|
515 |
* file, at which the next read or write occurs. The offset may be
|
|
516 |
* set beyond the end of the file. Setting the offset beyond the end
|
|
517 |
* of the file does not change the file length. The file length will
|
|
518 |
* change only by writing after the offset has been set beyond the end
|
|
519 |
* of the file.
|
|
520 |
*
|
|
521 |
* @param pos the offset position, measured in bytes from the
|
|
522 |
* beginning of the file, at which to set the file
|
|
523 |
* pointer.
|
|
524 |
* @exception IOException if <code>pos</code> is less than
|
|
525 |
* <code>0</code> or if an I/O error occurs.
|
|
526 |
*/
|
|
527 |
public native void seek(long pos) throws IOException;
|
|
528 |
|
|
529 |
/**
|
|
530 |
* Returns the length of this file.
|
|
531 |
*
|
|
532 |
* @return the length of this file, measured in bytes.
|
|
533 |
* @exception IOException if an I/O error occurs.
|
|
534 |
*/
|
|
535 |
public native long length() throws IOException;
|
|
536 |
|
|
537 |
/**
|
|
538 |
* Sets the length of this file.
|
|
539 |
*
|
|
540 |
* <p> If the present length of the file as returned by the
|
|
541 |
* <code>length</code> method is greater than the <code>newLength</code>
|
|
542 |
* argument then the file will be truncated. In this case, if the file
|
|
543 |
* offset as returned by the <code>getFilePointer</code> method is greater
|
|
544 |
* than <code>newLength</code> then after this method returns the offset
|
|
545 |
* will be equal to <code>newLength</code>.
|
|
546 |
*
|
|
547 |
* <p> If the present length of the file as returned by the
|
|
548 |
* <code>length</code> method is smaller than the <code>newLength</code>
|
|
549 |
* argument then the file will be extended. In this case, the contents of
|
|
550 |
* the extended portion of the file are not defined.
|
|
551 |
*
|
|
552 |
* @param newLength The desired length of the file
|
|
553 |
* @exception IOException If an I/O error occurs
|
|
554 |
* @since 1.2
|
|
555 |
*/
|
|
556 |
public native void setLength(long newLength) throws IOException;
|
|
557 |
|
|
558 |
/**
|
|
559 |
* Closes this random access file stream and releases any system
|
|
560 |
* resources associated with the stream. A closed random access
|
|
561 |
* file cannot perform input or output operations and cannot be
|
|
562 |
* reopened.
|
|
563 |
*
|
|
564 |
* <p> If this file has an associated channel then the channel is closed
|
|
565 |
* as well.
|
|
566 |
*
|
|
567 |
* @exception IOException if an I/O error occurs.
|
|
568 |
*
|
|
569 |
* @revised 1.4
|
|
570 |
* @spec JSR-51
|
|
571 |
*/
|
|
572 |
public void close() throws IOException {
|
|
573 |
synchronized (closeLock) {
|
|
574 |
if (closed) {
|
|
575 |
return;
|
|
576 |
}
|
|
577 |
closed = true;
|
|
578 |
}
|
|
579 |
if (channel != null) {
|
|
580 |
/*
|
|
581 |
* Decrement FD use count associated with the channel. The FD use
|
|
582 |
* count is incremented whenever a new channel is obtained from
|
|
583 |
* this stream.
|
|
584 |
*/
|
|
585 |
fd.decrementAndGetUseCount();
|
|
586 |
channel.close();
|
|
587 |
}
|
|
588 |
|
|
589 |
/*
|
|
590 |
* Decrement FD use count associated with this stream.
|
|
591 |
* The count got incremented by FileDescriptor during its construction.
|
|
592 |
*/
|
|
593 |
fd.decrementAndGetUseCount();
|
|
594 |
close0();
|
|
595 |
}
|
|
596 |
|
|
597 |
//
|
|
598 |
// Some "reading/writing Java data types" methods stolen from
|
|
599 |
// DataInputStream and DataOutputStream.
|
|
600 |
//
|
|
601 |
|
|
602 |
/**
|
|
603 |
* Reads a <code>boolean</code> from this file. This method reads a
|
|
604 |
* single byte from the file, starting at the current file pointer.
|
|
605 |
* A value of <code>0</code> represents
|
|
606 |
* <code>false</code>. Any other value represents <code>true</code>.
|
|
607 |
* This method blocks until the byte is read, the end of the stream
|
|
608 |
* is detected, or an exception is thrown.
|
|
609 |
*
|
|
610 |
* @return the <code>boolean</code> value read.
|
|
611 |
* @exception EOFException if this file has reached the end.
|
|
612 |
* @exception IOException if an I/O error occurs.
|
|
613 |
*/
|
|
614 |
public final boolean readBoolean() throws IOException {
|
|
615 |
int ch = this.read();
|
|
616 |
if (ch < 0)
|
|
617 |
throw new EOFException();
|
|
618 |
return (ch != 0);
|
|
619 |
}
|
|
620 |
|
|
621 |
/**
|
|
622 |
* Reads a signed eight-bit value from this file. This method reads a
|
|
623 |
* byte from the file, starting from the current file pointer.
|
|
624 |
* If the byte read is <code>b</code>, where
|
|
625 |
* <code>0 <= b <= 255</code>,
|
|
626 |
* then the result is:
|
|
627 |
* <blockquote><pre>
|
|
628 |
* (byte)(b)
|
|
629 |
* </pre></blockquote>
|
|
630 |
* <p>
|
|
631 |
* This method blocks until the byte is read, the end of the stream
|
|
632 |
* is detected, or an exception is thrown.
|
|
633 |
*
|
|
634 |
* @return the next byte of this file as a signed eight-bit
|
|
635 |
* <code>byte</code>.
|
|
636 |
* @exception EOFException if this file has reached the end.
|
|
637 |
* @exception IOException if an I/O error occurs.
|
|
638 |
*/
|
|
639 |
public final byte readByte() throws IOException {
|
|
640 |
int ch = this.read();
|
|
641 |
if (ch < 0)
|
|
642 |
throw new EOFException();
|
|
643 |
return (byte)(ch);
|
|
644 |
}
|
|
645 |
|
|
646 |
/**
|
|
647 |
* Reads an unsigned eight-bit number from this file. This method reads
|
|
648 |
* a byte from this file, starting at the current file pointer,
|
|
649 |
* and returns that byte.
|
|
650 |
* <p>
|
|
651 |
* This method blocks until the byte is read, the end of the stream
|
|
652 |
* is detected, or an exception is thrown.
|
|
653 |
*
|
|
654 |
* @return the next byte of this file, interpreted as an unsigned
|
|
655 |
* eight-bit number.
|
|
656 |
* @exception EOFException if this file has reached the end.
|
|
657 |
* @exception IOException if an I/O error occurs.
|
|
658 |
*/
|
|
659 |
public final int readUnsignedByte() throws IOException {
|
|
660 |
int ch = this.read();
|
|
661 |
if (ch < 0)
|
|
662 |
throw new EOFException();
|
|
663 |
return ch;
|
|
664 |
}
|
|
665 |
|
|
666 |
/**
|
|
667 |
* Reads a signed 16-bit number from this file. The method reads two
|
|
668 |
* bytes from this file, starting at the current file pointer.
|
|
669 |
* If the two bytes read, in order, are
|
|
670 |
* <code>b1</code> and <code>b2</code>, where each of the two values is
|
|
671 |
* between <code>0</code> and <code>255</code>, inclusive, then the
|
|
672 |
* result is equal to:
|
|
673 |
* <blockquote><pre>
|
|
674 |
* (short)((b1 << 8) | b2)
|
|
675 |
* </pre></blockquote>
|
|
676 |
* <p>
|
|
677 |
* This method blocks until the two bytes are read, the end of the
|
|
678 |
* stream is detected, or an exception is thrown.
|
|
679 |
*
|
|
680 |
* @return the next two bytes of this file, interpreted as a signed
|
|
681 |
* 16-bit number.
|
|
682 |
* @exception EOFException if this file reaches the end before reading
|
|
683 |
* two bytes.
|
|
684 |
* @exception IOException if an I/O error occurs.
|
|
685 |
*/
|
|
686 |
public final short readShort() throws IOException {
|
|
687 |
int ch1 = this.read();
|
|
688 |
int ch2 = this.read();
|
|
689 |
if ((ch1 | ch2) < 0)
|
|
690 |
throw new EOFException();
|
|
691 |
return (short)((ch1 << 8) + (ch2 << 0));
|
|
692 |
}
|
|
693 |
|
|
694 |
/**
|
|
695 |
* Reads an unsigned 16-bit number from this file. This method reads
|
|
696 |
* two bytes from the file, starting at the current file pointer.
|
|
697 |
* If the bytes read, in order, are
|
|
698 |
* <code>b1</code> and <code>b2</code>, where
|
|
699 |
* <code>0 <= b1, b2 <= 255</code>,
|
|
700 |
* then the result is equal to:
|
|
701 |
* <blockquote><pre>
|
|
702 |
* (b1 << 8) | b2
|
|
703 |
* </pre></blockquote>
|
|
704 |
* <p>
|
|
705 |
* This method blocks until the two bytes are read, the end of the
|
|
706 |
* stream is detected, or an exception is thrown.
|
|
707 |
*
|
|
708 |
* @return the next two bytes of this file, interpreted as an unsigned
|
|
709 |
* 16-bit integer.
|
|
710 |
* @exception EOFException if this file reaches the end before reading
|
|
711 |
* two bytes.
|
|
712 |
* @exception IOException if an I/O error occurs.
|
|
713 |
*/
|
|
714 |
public final int readUnsignedShort() throws IOException {
|
|
715 |
int ch1 = this.read();
|
|
716 |
int ch2 = this.read();
|
|
717 |
if ((ch1 | ch2) < 0)
|
|
718 |
throw new EOFException();
|
|
719 |
return (ch1 << 8) + (ch2 << 0);
|
|
720 |
}
|
|
721 |
|
|
722 |
/**
|
|
723 |
* Reads a character from this file. This method reads two
|
|
724 |
* bytes from the file, starting at the current file pointer.
|
|
725 |
* If the bytes read, in order, are
|
|
726 |
* <code>b1</code> and <code>b2</code>, where
|
|
727 |
* <code>0 <= b1, b2 <= 255</code>,
|
|
728 |
* then the result is equal to:
|
|
729 |
* <blockquote><pre>
|
|
730 |
* (char)((b1 << 8) | b2)
|
|
731 |
* </pre></blockquote>
|
|
732 |
* <p>
|
|
733 |
* This method blocks until the two bytes are read, the end of the
|
|
734 |
* stream is detected, or an exception is thrown.
|
|
735 |
*
|
|
736 |
* @return the next two bytes of this file, interpreted as a
|
|
737 |
* <code>char</code>.
|
|
738 |
* @exception EOFException if this file reaches the end before reading
|
|
739 |
* two bytes.
|
|
740 |
* @exception IOException if an I/O error occurs.
|
|
741 |
*/
|
|
742 |
public final char readChar() throws IOException {
|
|
743 |
int ch1 = this.read();
|
|
744 |
int ch2 = this.read();
|
|
745 |
if ((ch1 | ch2) < 0)
|
|
746 |
throw new EOFException();
|
|
747 |
return (char)((ch1 << 8) + (ch2 << 0));
|
|
748 |
}
|
|
749 |
|
|
750 |
/**
|
|
751 |
* Reads a signed 32-bit integer from this file. This method reads 4
|
|
752 |
* bytes from the file, starting at the current file pointer.
|
|
753 |
* If the bytes read, in order, are <code>b1</code>,
|
|
754 |
* <code>b2</code>, <code>b3</code>, and <code>b4</code>, where
|
|
755 |
* <code>0 <= b1, b2, b3, b4 <= 255</code>,
|
|
756 |
* then the result is equal to:
|
|
757 |
* <blockquote><pre>
|
|
758 |
* (b1 << 24) | (b2 << 16) + (b3 << 8) + b4
|
|
759 |
* </pre></blockquote>
|
|
760 |
* <p>
|
|
761 |
* This method blocks until the four bytes are read, the end of the
|
|
762 |
* stream is detected, or an exception is thrown.
|
|
763 |
*
|
|
764 |
* @return the next four bytes of this file, interpreted as an
|
|
765 |
* <code>int</code>.
|
|
766 |
* @exception EOFException if this file reaches the end before reading
|
|
767 |
* four bytes.
|
|
768 |
* @exception IOException if an I/O error occurs.
|
|
769 |
*/
|
|
770 |
public final int readInt() throws IOException {
|
|
771 |
int ch1 = this.read();
|
|
772 |
int ch2 = this.read();
|
|
773 |
int ch3 = this.read();
|
|
774 |
int ch4 = this.read();
|
|
775 |
if ((ch1 | ch2 | ch3 | ch4) < 0)
|
|
776 |
throw new EOFException();
|
|
777 |
return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
|
|
778 |
}
|
|
779 |
|
|
780 |
/**
|
|
781 |
* Reads a signed 64-bit integer from this file. This method reads eight
|
|
782 |
* bytes from the file, starting at the current file pointer.
|
|
783 |
* If the bytes read, in order, are
|
|
784 |
* <code>b1</code>, <code>b2</code>, <code>b3</code>,
|
|
785 |
* <code>b4</code>, <code>b5</code>, <code>b6</code>,
|
|
786 |
* <code>b7</code>, and <code>b8,</code> where:
|
|
787 |
* <blockquote><pre>
|
|
788 |
* 0 <= b1, b2, b3, b4, b5, b6, b7, b8 <=255,
|
|
789 |
* </pre></blockquote>
|
|
790 |
* <p>
|
|
791 |
* then the result is equal to:
|
|
792 |
* <p><blockquote><pre>
|
|
793 |
* ((long)b1 << 56) + ((long)b2 << 48)
|
|
794 |
* + ((long)b3 << 40) + ((long)b4 << 32)
|
|
795 |
* + ((long)b5 << 24) + ((long)b6 << 16)
|
|
796 |
* + ((long)b7 << 8) + b8
|
|
797 |
* </pre></blockquote>
|
|
798 |
* <p>
|
|
799 |
* This method blocks until the eight bytes are read, the end of the
|
|
800 |
* stream is detected, or an exception is thrown.
|
|
801 |
*
|
|
802 |
* @return the next eight bytes of this file, interpreted as a
|
|
803 |
* <code>long</code>.
|
|
804 |
* @exception EOFException if this file reaches the end before reading
|
|
805 |
* eight bytes.
|
|
806 |
* @exception IOException if an I/O error occurs.
|
|
807 |
*/
|
|
808 |
public final long readLong() throws IOException {
|
|
809 |
return ((long)(readInt()) << 32) + (readInt() & 0xFFFFFFFFL);
|
|
810 |
}
|
|
811 |
|
|
812 |
/**
|
|
813 |
* Reads a <code>float</code> from this file. This method reads an
|
|
814 |
* <code>int</code> value, starting at the current file pointer,
|
|
815 |
* as if by the <code>readInt</code> method
|
|
816 |
* and then converts that <code>int</code> to a <code>float</code>
|
|
817 |
* using the <code>intBitsToFloat</code> method in class
|
|
818 |
* <code>Float</code>.
|
|
819 |
* <p>
|
|
820 |
* This method blocks until the four bytes are read, the end of the
|
|
821 |
* stream is detected, or an exception is thrown.
|
|
822 |
*
|
|
823 |
* @return the next four bytes of this file, interpreted as a
|
|
824 |
* <code>float</code>.
|
|
825 |
* @exception EOFException if this file reaches the end before reading
|
|
826 |
* four bytes.
|
|
827 |
* @exception IOException if an I/O error occurs.
|
|
828 |
* @see java.io.RandomAccessFile#readInt()
|
|
829 |
* @see java.lang.Float#intBitsToFloat(int)
|
|
830 |
*/
|
|
831 |
public final float readFloat() throws IOException {
|
|
832 |
return Float.intBitsToFloat(readInt());
|
|
833 |
}
|
|
834 |
|
|
835 |
/**
|
|
836 |
* Reads a <code>double</code> from this file. This method reads a
|
|
837 |
* <code>long</code> value, starting at the current file pointer,
|
|
838 |
* as if by the <code>readLong</code> method
|
|
839 |
* and then converts that <code>long</code> to a <code>double</code>
|
|
840 |
* using the <code>longBitsToDouble</code> method in
|
|
841 |
* class <code>Double</code>.
|
|
842 |
* <p>
|
|
843 |
* This method blocks until the eight bytes are read, the end of the
|
|
844 |
* stream is detected, or an exception is thrown.
|
|
845 |
*
|
|
846 |
* @return the next eight bytes of this file, interpreted as a
|
|
847 |
* <code>double</code>.
|
|
848 |
* @exception EOFException if this file reaches the end before reading
|
|
849 |
* eight bytes.
|
|
850 |
* @exception IOException if an I/O error occurs.
|
|
851 |
* @see java.io.RandomAccessFile#readLong()
|
|
852 |
* @see java.lang.Double#longBitsToDouble(long)
|
|
853 |
*/
|
|
854 |
public final double readDouble() throws IOException {
|
|
855 |
return Double.longBitsToDouble(readLong());
|
|
856 |
}
|
|
857 |
|
|
858 |
/**
|
|
859 |
* Reads the next line of text from this file. This method successively
|
|
860 |
* reads bytes from the file, starting at the current file pointer,
|
|
861 |
* until it reaches a line terminator or the end
|
|
862 |
* of the file. Each byte is converted into a character by taking the
|
|
863 |
* byte's value for the lower eight bits of the character and setting the
|
|
864 |
* high eight bits of the character to zero. This method does not,
|
|
865 |
* therefore, support the full Unicode character set.
|
|
866 |
*
|
|
867 |
* <p> A line of text is terminated by a carriage-return character
|
|
868 |
* (<code>'\r'</code>), a newline character (<code>'\n'</code>), a
|
|
869 |
* carriage-return character immediately followed by a newline character,
|
|
870 |
* or the end of the file. Line-terminating characters are discarded and
|
|
871 |
* are not included as part of the string returned.
|
|
872 |
*
|
|
873 |
* <p> This method blocks until a newline character is read, a carriage
|
|
874 |
* return and the byte following it are read (to see if it is a newline),
|
|
875 |
* the end of the file is reached, or an exception is thrown.
|
|
876 |
*
|
|
877 |
* @return the next line of text from this file, or null if end
|
|
878 |
* of file is encountered before even one byte is read.
|
|
879 |
* @exception IOException if an I/O error occurs.
|
|
880 |
*/
|
|
881 |
|
|
882 |
public final String readLine() throws IOException {
|
|
883 |
StringBuffer input = new StringBuffer();
|
|
884 |
int c = -1;
|
|
885 |
boolean eol = false;
|
|
886 |
|
|
887 |
while (!eol) {
|
|
888 |
switch (c = read()) {
|
|
889 |
case -1:
|
|
890 |
case '\n':
|
|
891 |
eol = true;
|
|
892 |
break;
|
|
893 |
case '\r':
|
|
894 |
eol = true;
|
|
895 |
long cur = getFilePointer();
|
|
896 |
if ((read()) != '\n') {
|
|
897 |
seek(cur);
|
|
898 |
}
|
|
899 |
break;
|
|
900 |
default:
|
|
901 |
input.append((char)c);
|
|
902 |
break;
|
|
903 |
}
|
|
904 |
}
|
|
905 |
|
|
906 |
if ((c == -1) && (input.length() == 0)) {
|
|
907 |
return null;
|
|
908 |
}
|
|
909 |
return input.toString();
|
|
910 |
}
|
|
911 |
|
|
912 |
/**
|
|
913 |
* Reads in a string from this file. The string has been encoded
|
|
914 |
* using a
|
|
915 |
* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
|
|
916 |
* format.
|
|
917 |
* <p>
|
|
918 |
* The first two bytes are read, starting from the current file
|
|
919 |
* pointer, as if by
|
|
920 |
* <code>readUnsignedShort</code>. This value gives the number of
|
|
921 |
* following bytes that are in the encoded string, not
|
|
922 |
* the length of the resulting string. The following bytes are then
|
|
923 |
* interpreted as bytes encoding characters in the modified UTF-8 format
|
|
924 |
* and are converted into characters.
|
|
925 |
* <p>
|
|
926 |
* This method blocks until all the bytes are read, the end of the
|
|
927 |
* stream is detected, or an exception is thrown.
|
|
928 |
*
|
|
929 |
* @return a Unicode string.
|
|
930 |
* @exception EOFException if this file reaches the end before
|
|
931 |
* reading all the bytes.
|
|
932 |
* @exception IOException if an I/O error occurs.
|
|
933 |
* @exception UTFDataFormatException if the bytes do not represent
|
|
934 |
* valid modified UTF-8 encoding of a Unicode string.
|
|
935 |
* @see java.io.RandomAccessFile#readUnsignedShort()
|
|
936 |
*/
|
|
937 |
public final String readUTF() throws IOException {
|
|
938 |
return DataInputStream.readUTF(this);
|
|
939 |
}
|
|
940 |
|
|
941 |
/**
|
|
942 |
* Writes a <code>boolean</code> to the file as a one-byte value. The
|
|
943 |
* value <code>true</code> is written out as the value
|
|
944 |
* <code>(byte)1</code>; the value <code>false</code> is written out
|
|
945 |
* as the value <code>(byte)0</code>. The write starts at
|
|
946 |
* the current position of the file pointer.
|
|
947 |
*
|
|
948 |
* @param v a <code>boolean</code> value to be written.
|
|
949 |
* @exception IOException if an I/O error occurs.
|
|
950 |
*/
|
|
951 |
public final void writeBoolean(boolean v) throws IOException {
|
|
952 |
write(v ? 1 : 0);
|
|
953 |
//written++;
|
|
954 |
}
|
|
955 |
|
|
956 |
/**
|
|
957 |
* Writes a <code>byte</code> to the file as a one-byte value. The
|
|
958 |
* write starts at the current position of the file pointer.
|
|
959 |
*
|
|
960 |
* @param v a <code>byte</code> value to be written.
|
|
961 |
* @exception IOException if an I/O error occurs.
|
|
962 |
*/
|
|
963 |
public final void writeByte(int v) throws IOException {
|
|
964 |
write(v);
|
|
965 |
//written++;
|
|
966 |
}
|
|
967 |
|
|
968 |
/**
|
|
969 |
* Writes a <code>short</code> to the file as two bytes, high byte first.
|
|
970 |
* The write starts at the current position of the file pointer.
|
|
971 |
*
|
|
972 |
* @param v a <code>short</code> to be written.
|
|
973 |
* @exception IOException if an I/O error occurs.
|
|
974 |
*/
|
|
975 |
public final void writeShort(int v) throws IOException {
|
|
976 |
write((v >>> 8) & 0xFF);
|
|
977 |
write((v >>> 0) & 0xFF);
|
|
978 |
//written += 2;
|
|
979 |
}
|
|
980 |
|
|
981 |
/**
|
|
982 |
* Writes a <code>char</code> to the file as a two-byte value, high
|
|
983 |
* byte first. The write starts at the current position of the
|
|
984 |
* file pointer.
|
|
985 |
*
|
|
986 |
* @param v a <code>char</code> value to be written.
|
|
987 |
* @exception IOException if an I/O error occurs.
|
|
988 |
*/
|
|
989 |
public final void writeChar(int v) throws IOException {
|
|
990 |
write((v >>> 8) & 0xFF);
|
|
991 |
write((v >>> 0) & 0xFF);
|
|
992 |
//written += 2;
|
|
993 |
}
|
|
994 |
|
|
995 |
/**
|
|
996 |
* Writes an <code>int</code> to the file as four bytes, high byte first.
|
|
997 |
* The write starts at the current position of the file pointer.
|
|
998 |
*
|
|
999 |
* @param v an <code>int</code> to be written.
|
|
1000 |
* @exception IOException if an I/O error occurs.
|
|
1001 |
*/
|
|
1002 |
public final void writeInt(int v) throws IOException {
|
|
1003 |
write((v >>> 24) & 0xFF);
|
|
1004 |
write((v >>> 16) & 0xFF);
|
|
1005 |
write((v >>> 8) & 0xFF);
|
|
1006 |
write((v >>> 0) & 0xFF);
|
|
1007 |
//written += 4;
|
|
1008 |
}
|
|
1009 |
|
|
1010 |
/**
|
|
1011 |
* Writes a <code>long</code> to the file as eight bytes, high byte first.
|
|
1012 |
* The write starts at the current position of the file pointer.
|
|
1013 |
*
|
|
1014 |
* @param v a <code>long</code> to be written.
|
|
1015 |
* @exception IOException if an I/O error occurs.
|
|
1016 |
*/
|
|
1017 |
public final void writeLong(long v) throws IOException {
|
|
1018 |
write((int)(v >>> 56) & 0xFF);
|
|
1019 |
write((int)(v >>> 48) & 0xFF);
|
|
1020 |
write((int)(v >>> 40) & 0xFF);
|
|
1021 |
write((int)(v >>> 32) & 0xFF);
|
|
1022 |
write((int)(v >>> 24) & 0xFF);
|
|
1023 |
write((int)(v >>> 16) & 0xFF);
|
|
1024 |
write((int)(v >>> 8) & 0xFF);
|
|
1025 |
write((int)(v >>> 0) & 0xFF);
|
|
1026 |
//written += 8;
|
|
1027 |
}
|
|
1028 |
|
|
1029 |
/**
|
|
1030 |
* Converts the float argument to an <code>int</code> using the
|
|
1031 |
* <code>floatToIntBits</code> method in class <code>Float</code>,
|
|
1032 |
* and then writes that <code>int</code> value to the file as a
|
|
1033 |
* four-byte quantity, high byte first. The write starts at the
|
|
1034 |
* current position of the file pointer.
|
|
1035 |
*
|
|
1036 |
* @param v a <code>float</code> value to be written.
|
|
1037 |
* @exception IOException if an I/O error occurs.
|
|
1038 |
* @see java.lang.Float#floatToIntBits(float)
|
|
1039 |
*/
|
|
1040 |
public final void writeFloat(float v) throws IOException {
|
|
1041 |
writeInt(Float.floatToIntBits(v));
|
|
1042 |
}
|
|
1043 |
|
|
1044 |
/**
|
|
1045 |
* Converts the double argument to a <code>long</code> using the
|
|
1046 |
* <code>doubleToLongBits</code> method in class <code>Double</code>,
|
|
1047 |
* and then writes that <code>long</code> value to the file as an
|
|
1048 |
* eight-byte quantity, high byte first. The write starts at the current
|
|
1049 |
* position of the file pointer.
|
|
1050 |
*
|
|
1051 |
* @param v a <code>double</code> value to be written.
|
|
1052 |
* @exception IOException if an I/O error occurs.
|
|
1053 |
* @see java.lang.Double#doubleToLongBits(double)
|
|
1054 |
*/
|
|
1055 |
public final void writeDouble(double v) throws IOException {
|
|
1056 |
writeLong(Double.doubleToLongBits(v));
|
|
1057 |
}
|
|
1058 |
|
|
1059 |
/**
|
|
1060 |
* Writes the string to the file as a sequence of bytes. Each
|
|
1061 |
* character in the string is written out, in sequence, by discarding
|
|
1062 |
* its high eight bits. The write starts at the current position of
|
|
1063 |
* the file pointer.
|
|
1064 |
*
|
|
1065 |
* @param s a string of bytes to be written.
|
|
1066 |
* @exception IOException if an I/O error occurs.
|
|
1067 |
*/
|
|
1068 |
public final void writeBytes(String s) throws IOException {
|
|
1069 |
int len = s.length();
|
|
1070 |
byte[] b = new byte[len];
|
|
1071 |
s.getBytes(0, len, b, 0);
|
|
1072 |
writeBytes(b, 0, len);
|
|
1073 |
}
|
|
1074 |
|
|
1075 |
/**
|
|
1076 |
* Writes a string to the file as a sequence of characters. Each
|
|
1077 |
* character is written to the data output stream as if by the
|
|
1078 |
* <code>writeChar</code> method. The write starts at the current
|
|
1079 |
* position of the file pointer.
|
|
1080 |
*
|
|
1081 |
* @param s a <code>String</code> value to be written.
|
|
1082 |
* @exception IOException if an I/O error occurs.
|
|
1083 |
* @see java.io.RandomAccessFile#writeChar(int)
|
|
1084 |
*/
|
|
1085 |
public final void writeChars(String s) throws IOException {
|
|
1086 |
int clen = s.length();
|
|
1087 |
int blen = 2*clen;
|
|
1088 |
byte[] b = new byte[blen];
|
|
1089 |
char[] c = new char[clen];
|
|
1090 |
s.getChars(0, clen, c, 0);
|
|
1091 |
for (int i = 0, j = 0; i < clen; i++) {
|
|
1092 |
b[j++] = (byte)(c[i] >>> 8);
|
|
1093 |
b[j++] = (byte)(c[i] >>> 0);
|
|
1094 |
}
|
|
1095 |
writeBytes(b, 0, blen);
|
|
1096 |
}
|
|
1097 |
|
|
1098 |
/**
|
|
1099 |
* Writes a string to the file using
|
|
1100 |
* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
|
|
1101 |
* encoding in a machine-independent manner.
|
|
1102 |
* <p>
|
|
1103 |
* First, two bytes are written to the file, starting at the
|
|
1104 |
* current file pointer, as if by the
|
|
1105 |
* <code>writeShort</code> method giving the number of bytes to
|
|
1106 |
* follow. This value is the number of bytes actually written out,
|
|
1107 |
* not the length of the string. Following the length, each character
|
|
1108 |
* of the string is output, in sequence, using the modified UTF-8 encoding
|
|
1109 |
* for each character.
|
|
1110 |
*
|
|
1111 |
* @param str a string to be written.
|
|
1112 |
* @exception IOException if an I/O error occurs.
|
|
1113 |
*/
|
|
1114 |
public final void writeUTF(String str) throws IOException {
|
|
1115 |
DataOutputStream.writeUTF(str, this);
|
|
1116 |
}
|
|
1117 |
|
|
1118 |
private static native void initIDs();
|
|
1119 |
|
|
1120 |
private native void close0() throws IOException;
|
|
1121 |
|
|
1122 |
static {
|
|
1123 |
initIDs();
|
|
1124 |
}
|
|
1125 |
}
|