/*
* Copyright 1998-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package sun.misc;
import java.net.URL;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.io.InputStream;
import java.security.CodeSigner;
import java.util.jar.Manifest;
import java.util.jar.Attributes;
import java.nio.ByteBuffer;
import sun.nio.ByteBuffered;
/**
* This class is used to represent a Resource that has been loaded
* from the class path.
*
* @author David Connelly
* @since 1.2
*/
public abstract class Resource {
/**
* Returns the name of the Resource.
*/
public abstract String getName();
/**
* Returns the URL of the Resource.
*/
public abstract URL getURL();
/**
* Returns the CodeSource URL for the Resource.
*/
public abstract URL getCodeSourceURL();
/**
* Returns an InputStream for reading the Resource data.
*/
public abstract InputStream getInputStream() throws IOException;
/**
* Returns the length of the Resource data, or -1 if unknown.
*/
public abstract int getContentLength() throws IOException;
private InputStream cis;
/* Cache result in case getBytes is called after getByteBuffer. */
private synchronized InputStream cachedInputStream() throws IOException {
if (cis == null) {
cis = getInputStream();
}
return cis;
}
/**
* Returns the Resource data as an array of bytes.
*/
public byte[] getBytes() throws IOException {
byte[] b;
// Get stream before content length so that a FileNotFoundException
// can propagate upwards without being caught too early
InputStream in = cachedInputStream();
// This code has been uglified to protect against interrupts.
// Even if a thread has been interrupted when loading resources,
// the IO should not abort, so must carefully retry, failing only
// if the retry leads to some other IO exception.
boolean isInterrupted = Thread.interrupted();
int len;
for (;;) {
try {
len = getContentLength();
break;
} catch (InterruptedIOException iioe) {
Thread.interrupted();
isInterrupted = true;
}
}
try {
if (len != -1) {
// Read exactly len bytes from the input stream
b = new byte[len];
while (len > 0) {
int n = 0;
try {
n = in.read(b, b.length - len, len);
} catch (InterruptedIOException iioe) {
Thread.interrupted();
isInterrupted = true;
}
if (n == -1) {
throw new IOException("unexpected EOF");
}
len -= n;
}
} else {
// Read until end of stream is reached
b = new byte[1024];
int total = 0;
for (;;) {
len = 0;
try {
len = in.read(b, total, b.length - total);
if (len == -1)
break;
} catch (InterruptedIOException iioe) {
Thread.interrupted();
isInterrupted = true;
}
total += len;
if (total >= b.length) {
byte[] tmp = new byte[total * 2];
System.arraycopy(b, 0, tmp, 0, total);
b = tmp;
}
}
// Trim array to correct size, if necessary
if (total != b.length) {
byte[] tmp = new byte[total];
System.arraycopy(b, 0, tmp, 0, total);
b = tmp;
}
}
} finally {
try {
in.close();
} catch (InterruptedIOException iioe) {
isInterrupted = true;
} catch (IOException ignore) {}
if (isInterrupted) {
Thread.currentThread().interrupt();
}
}
return b;
}
/**
* Returns the Resource data as a ByteBuffer, but only if the input stream
* was implemented on top of a ByteBuffer. Return <tt>null</tt> otherwise.
*/
public ByteBuffer getByteBuffer() throws IOException {
InputStream in = cachedInputStream();
if (in instanceof ByteBuffered) {
return ((ByteBuffered)in).getByteBuffer();
}
return null;
}
/**
* Returns the Manifest for the Resource, or null if none.
*/
public Manifest getManifest() throws IOException {
return null;
}
/**
* Returns theCertificates for the Resource, or null if none.
*/
public java.security.cert.Certificate[] getCertificates() {
return null;
}
/**
* Returns the code signers for the Resource, or null if none.
*/
public CodeSigner[] getCodeSigners() {
return null;
}
}