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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
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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
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 * accompanied this code).
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package jdk.internal.loader;

import java.io.EOFException;
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.nio.ByteBuffer;
import java.util.Arrays;
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
/** * 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.
/** * Returns the name of the Resource. */
public abstract String getName();
Returns the URL of the Resource.
/** * Returns the URL of the Resource. */
public abstract URL getURL();
Returns the CodeSource URL for the Resource.
/** * Returns the CodeSource URL for the Resource. */
public abstract URL getCodeSourceURL();
Returns an InputStream for reading the Resource data.
/** * 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.
/** * 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.
/** * 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 { b = new byte[0]; if (len == -1) len = Integer.MAX_VALUE; int pos = 0; while (pos < len) { int bytesToRead; if (pos >= b.length) { // Only expand when there's no room bytesToRead = Math.min(len - pos, b.length + 1024); if (bytesToRead < 0) { // Can overflow only due to large b.length bytesToRead = len - pos; } b = Arrays.copyOf(b, pos + bytesToRead); } else { bytesToRead = b.length - pos; } int cc = 0; try { cc = in.read(b, pos, bytesToRead); } catch (InterruptedIOException iioe) { Thread.interrupted(); isInterrupted = true; } if (cc < 0) { if (len != Integer.MAX_VALUE) { throw new EOFException("Detect premature EOF"); } else { if (b.length != pos) { b = Arrays.copyOf(b, pos); } break; } } pos += cc; } } 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 null otherwise.
Returns:Resource data or null.
/** * Returns the Resource data as a ByteBuffer, but only if the input stream * was implemented on top of a ByteBuffer. Return {@code null} otherwise. * @return Resource data or null. */
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.
/** * 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.
/** * 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.
/** * Returns the code signers for the Resource, or null if none. */
public CodeSigner[] getCodeSigners() { return null; } }