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AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during
compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based
@AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step.
This library is a superset of AspectJ weaver and hence also of AspectJ runtime.
/*******************************************************************************
* Copyright (c) 2003, 2011 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.osgi.framework.internal.reliablefile;
import java.io.*;
/**
* A ReliableFile FileInputStream replacement class.
* This class can be used just like FileInputStream. The class
* is in partnership with ReliableFileOutputStream to avoid losing
* file data by using multiple files.
*
* @see ReliableFileOutputStream
*/
public class ReliableFileInputStream extends FilterInputStream {
/**
* ReliableFile object for this file.
*/
private ReliableFile reliable;
/**
* size of crc and signature
*/
private int sigSize;
/**
* current position reading from file
*/
private long readPos;
/**
* total file length available for reading
*/
private long length;
/**
* Constructs a new ReliableFileInputStream on the file named name. If the
* file does not exist, the FileNotFoundException is thrown.
* The name may be absolute or relative
* to the System property "user.dir".
*
* @param name the file on which to stream reads.
* @exception java.io.IOException If an error occurs opening the file.
*/
public ReliableFileInputStream(String name) throws IOException {
this(ReliableFile.getReliableFile(name), ReliableFile.GENERATION_LATEST, ReliableFile.OPEN_BEST_AVAILABLE);
}
/**
* Constructs a new ReliableFileInputStream on the File file. If the
* file does not exist, the FileNotFoundException is thrown.
*
* @param file the File on which to stream reads.
* @exception java.io.IOException If an error occurs opening the file.
*/
public ReliableFileInputStream(File file) throws IOException {
this(ReliableFile.getReliableFile(file), ReliableFile.GENERATION_LATEST, ReliableFile.OPEN_BEST_AVAILABLE);
}
/**
* Constructs a new ReliableFileInputStream on the File file. If the
* file does not exist, the FileNotFoundException is thrown.
*
* @param file the File on which to stream reads.
* @param generation a specific generation requested.
* @param openMask mask used to open data.
* are invalid (corrupt, missing, etc).
* @exception java.io.IOException If an error occurs opening the file.
*/
public ReliableFileInputStream(File file, int generation, int openMask) throws IOException {
this(ReliableFile.getReliableFile(file), generation, openMask);
}
/**
*
* @param reliable The ReliableFile on which to read.
* @param generation a specific generation requested.
* @param openMask mask used to open data.
* are invalid (corrupt, missing, etc).
* @throws IOException If an error occurs opening the file.
*/
private ReliableFileInputStream(ReliableFile reliable, int generation, int openMask) throws IOException {
super(reliable.getInputStream(generation, openMask));
this.reliable = reliable;
sigSize = reliable.getSignatureSize();
readPos = 0;
this.length = reliable.getInputLength();
if (sigSize > length)
length = 0; // shouldn't ever happen
else
length -= sigSize;
}
/**
* Closes this input stream and releases any system resources associated
* with the stream.
*
* @exception java.io.IOException If an error occurs closing the file.
*/
@Override
public synchronized void close() throws IOException {
if (reliable != null) {
try {
super.close();
} finally {
reliable.closeInputFile();
reliable = null;
}
}
}
/**
* Override default FilterInputStream method.
* @see FilterInputStream#read(byte[], int, int)
*/
@Override
public synchronized int read(byte b[], int off, int len) throws IOException {
if (readPos >= length) {
return -1;
}
int num = super.read(b, off, len);
if (num != -1) {
if (num + readPos > length) {
num = (int) (length - readPos);
}
readPos += num;
}
return num;
}
/**
* Override default FilterInputStream method.
* @see FilterInputStream#read(byte[])
*/
@Override
public synchronized int read(byte b[]) throws IOException {
return read(b, 0, b.length);
}
/**
* Override default FilterInputStream method.
* @see FilterInputStream#read()
*/
@Override
public synchronized int read() throws IOException {
if (readPos >= length) {
return -1;
}
int num = super.read();
if (num != -1) {
readPos++;
}
return num;
}
/**
* Override default available method.
* @throws IOException
* @see FilterInputStream#available()
*/
@Override
public synchronized int available() throws IOException {
if (readPos < length) // just in case
return (int) (length - readPos);
return 0;
}
/**
* Override default skip method.
* @see FilterInputStream#skip(long)
*/
@Override
public synchronized long skip(long n) throws IOException {
long len = super.skip(n);
if (readPos + len > length)
len = length - readPos;
readPos += len;
return len;
}
/**
* Override default markSupported method.
* @see FilterInputStream#markSupported()
*/
@Override
public boolean markSupported() {
return false;
}
/**
* Override default mark method.
* @see FilterInputStream#mark(int)
*/
@Override
public void mark(int readlimit) {
//ignore
}
/**
* Override default reset method.
* @see FilterInputStream#reset()
*/
@Override
public void reset() throws IOException {
throw new IOException("reset not supported."); //$NON-NLS-1$
}
}