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package sun.nio.ch;

import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.nio.channels.spi.*;
import java.util.Objects;

This class is defined here rather than in java.nio.channels.Channels so that code can be shared with SocketAdaptor.
Author:Mike McCloskey, Mark Reinhold
Since:1.4
/** * This class is defined here rather than in java.nio.channels.Channels * so that code can be shared with SocketAdaptor. * * @author Mike McCloskey * @author Mark Reinhold * @since 1.4 */
public class ChannelInputStream extends InputStream { public static int read(ReadableByteChannel ch, ByteBuffer bb, boolean block) throws IOException { if (ch instanceof SelectableChannel) { SelectableChannel sc = (SelectableChannel)ch; synchronized (sc.blockingLock()) { boolean bm = sc.isBlocking(); if (!bm) throw new IllegalBlockingModeException(); if (bm != block) sc.configureBlocking(block); int n = ch.read(bb); if (bm != block) sc.configureBlocking(bm); return n; } } else { return ch.read(bb); } } protected final ReadableByteChannel ch; private ByteBuffer bb = null; private byte[] bs = null; // Invoker's previous array private byte[] b1 = null; public ChannelInputStream(ReadableByteChannel ch) { this.ch = ch; } public synchronized int read() throws IOException { if (b1 == null) b1 = new byte[1]; int n = this.read(b1); if (n == 1) return b1[0] & 0xff; return -1; } public synchronized int read(byte[] bs, int off, int len) throws IOException { Objects.checkFromIndexSize(off, len, bs.length); if (len == 0) return 0; ByteBuffer bb = ((this.bs == bs) ? this.bb : ByteBuffer.wrap(bs)); bb.limit(Math.min(off + len, bb.capacity())); bb.position(off); this.bb = bb; this.bs = bs; return read(bb); } protected int read(ByteBuffer bb) throws IOException { return ChannelInputStream.read(ch, bb, true); } public int available() throws IOException { // special case where the channel is to a file if (ch instanceof SeekableByteChannel) { SeekableByteChannel sbc = (SeekableByteChannel)ch; long rem = Math.max(0, sbc.size() - sbc.position()); return (rem > Integer.MAX_VALUE) ? Integer.MAX_VALUE : (int)rem; } return 0; } public synchronized long skip(long n) throws IOException { // special case where the channel is to a file if (ch instanceof SeekableByteChannel) { SeekableByteChannel sbc = (SeekableByteChannel)ch; long pos = sbc.position(); long newPos; if (n > 0) { newPos = pos + n; long size = sbc.size(); if (newPos < 0 || newPos > size) { newPos = size; } } else { newPos = Long.max(pos + n, 0); } sbc.position(newPos); return newPos - pos; } return super.skip(n); } public void close() throws IOException { ch.close(); } }