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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package sun.nio.ch;

import java.lang.invoke.ConstantBootstraps;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.VarHandle;
import java.nio.channels.CancelledKeyException;
import java.nio.channels.SelectableChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.spi.AbstractSelectionKey;


An implementation of SelectionKey.
/** * An implementation of SelectionKey. */
public final class SelectionKeyImpl extends AbstractSelectionKey { private static final VarHandle INTERESTOPS = ConstantBootstraps.fieldVarHandle( MethodHandles.lookup(), "interestOps", VarHandle.class, SelectionKeyImpl.class, int.class); private final SelChImpl channel; private final SelectorImpl selector; private volatile int interestOps; private volatile int readyOps; // registered events in kernel, used by some Selector implementations private int registeredEvents; // registered events need to be reset, used by some Selector implementations private volatile boolean reset; // index of key in pollfd array, used by some Selector implementations private int index; SelectionKeyImpl(SelChImpl ch, SelectorImpl sel) { channel = ch; selector = sel; } private void ensureValid() { if (!isValid()) throw new CancelledKeyException(); } int getFDVal() { return channel.getFDVal(); } @Override public SelectableChannel channel() { return (SelectableChannel)channel; } @Override public Selector selector() { return selector; } @Override public int interestOps() { ensureValid(); return interestOps; } @Override public SelectionKey interestOps(int ops) { ensureValid(); if ((ops & ~channel().validOps()) != 0) throw new IllegalArgumentException(); int oldOps = (int) INTERESTOPS.getAndSet(this, ops); if (ops != oldOps) { selector.setEventOps(this); } return this; } @Override public int interestOpsOr(int ops) { ensureValid(); if ((ops & ~channel().validOps()) != 0) throw new IllegalArgumentException(); int oldVal = (int) INTERESTOPS.getAndBitwiseOr(this, ops); if (oldVal != (oldVal | ops)) { selector.setEventOps(this); } return oldVal; } @Override public int interestOpsAnd(int ops) { ensureValid(); int oldVal = (int) INTERESTOPS.getAndBitwiseAnd(this, ops); if (oldVal != (oldVal & ops)) { selector.setEventOps(this); } return oldVal; } @Override public int readyOps() { ensureValid(); return readyOps; } // The nio versions of these operations do not care if a key // has been invalidated. They are for internal use by nio code. public void nioReadyOps(int ops) { readyOps = ops; } public int nioReadyOps() { return readyOps; } public SelectionKey nioInterestOps(int ops) { if ((ops & ~channel().validOps()) != 0) throw new IllegalArgumentException(); interestOps = ops; selector.setEventOps(this); return this; } public int nioInterestOps() { return interestOps; } int translateInterestOps() { return channel.translateInterestOps(interestOps); } boolean translateAndSetReadyOps(int ops) { return channel.translateAndSetReadyOps(ops, this); } boolean translateAndUpdateReadyOps(int ops) { return channel.translateAndUpdateReadyOps(ops, this); } void registeredEvents(int events) { // assert Thread.holdsLock(selector); this.registeredEvents = events; } int registeredEvents() { // assert Thread.holdsLock(selector); return registeredEvents; } int getIndex() { return index; } void setIndex(int i) { index = i; }
Sets the reset flag, re-queues the key, and wakeups up the Selector
/** * Sets the reset flag, re-queues the key, and wakeups up the Selector */
void reset() { reset = true; selector.setEventOps(this); selector.wakeup(); }
Clears the reset flag, returning the previous value of the flag
/** * Clears the reset flag, returning the previous value of the flag */
boolean getAndClearReset() { assert Thread.holdsLock(selector); boolean r = reset; if (r) reset = false; return r; } @Override public String toString() { StringBuilder sb = new StringBuilder(); sb.append("channel=") .append(channel) .append(", selector=") .append(selector); if (isValid()) { sb.append(", interestOps=") .append(interestOps) .append(", readyOps=") .append(readyOps); } else { sb.append(", invalid"); } return sb.toString(); } // used by Selector implementations to record when the key was selected int lastPolled; }