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package sun.nio.ch;

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


An abstract selector impl.
/** * An abstract selector impl. */
abstract class AbstractPollSelectorImpl extends SelectorImpl { // The poll fd array PollArrayWrapper pollWrapper; // Initial capacity of the pollfd array protected final int INIT_CAP = 10; // The list of SelectableChannels serviced by this Selector protected SelectionKeyImpl[] channelArray; // In some impls the first entry of channelArray is bogus protected int channelOffset = 0; // The number of valid channels in this Selector's poll array protected int totalChannels; // True if this Selector has been closed private boolean closed = false; // Lock for close and cleanup private Object closeLock = new Object(); AbstractPollSelectorImpl(SelectorProvider sp, int channels, int offset) { super(sp); this.totalChannels = channels; this.channelOffset = offset; } public void putEventOps(SelectionKeyImpl sk, int ops) { synchronized (closeLock) { if (closed) throw new ClosedSelectorException(); pollWrapper.putEventOps(sk.getIndex(), ops); } } public Selector wakeup() { pollWrapper.interrupt(); return this; } protected abstract int doSelect(long timeout) throws IOException; protected void implClose() throws IOException { synchronized (closeLock) { if (closed) return; closed = true; // Deregister channels for(int i=channelOffset; i<totalChannels; i++) { SelectionKeyImpl ski = channelArray[i]; assert(ski.getIndex() != -1); ski.setIndex(-1); deregister(ski); SelectableChannel selch = channelArray[i].channel(); if (!selch.isOpen() && !selch.isRegistered()) ((SelChImpl)selch).kill(); } implCloseInterrupt(); pollWrapper.free(); pollWrapper = null; selectedKeys = null; channelArray = null; totalChannels = 0; } } protected abstract void implCloseInterrupt() throws IOException;
Copy the information in the pollfd structs into the opss of the corresponding Channels. Add the ready keys to the ready queue.
/** * Copy the information in the pollfd structs into the opss * of the corresponding Channels. Add the ready keys to the * ready queue. */
protected int updateSelectedKeys() { int numKeysUpdated = 0; // Skip zeroth entry; it is for interrupts only for (int i=channelOffset; i<totalChannels; i++) { int rOps = pollWrapper.getReventOps(i); if (rOps != 0) { SelectionKeyImpl sk = channelArray[i]; pollWrapper.putReventOps(i, 0); if (selectedKeys.contains(sk)) { if (sk.channel.translateAndSetReadyOps(rOps, sk)) { numKeysUpdated++; } } else { sk.channel.translateAndSetReadyOps(rOps, sk); if ((sk.nioReadyOps() & sk.nioInterestOps()) != 0) { selectedKeys.add(sk); numKeysUpdated++; } } } } return numKeysUpdated; } protected void implRegister(SelectionKeyImpl ski) { synchronized (closeLock) { if (closed) throw new ClosedSelectorException(); // Check to see if the array is large enough if (channelArray.length == totalChannels) { // Make a larger array int newSize = pollWrapper.totalChannels * 2; SelectionKeyImpl temp[] = new SelectionKeyImpl[newSize]; // Copy over for (int i=channelOffset; i<totalChannels; i++) temp[i] = channelArray[i]; channelArray = temp; // Grow the NativeObject poll array pollWrapper.grow(newSize); } channelArray[totalChannels] = ski; ski.setIndex(totalChannels); pollWrapper.addEntry(ski.channel); totalChannels++; keys.add(ski); } } protected void implDereg(SelectionKeyImpl ski) throws IOException { // Algorithm: Copy the sc from the end of the list and put it into // the location of the sc to be removed (since order doesn't // matter). Decrement the sc count. Update the index of the sc // that is moved. int i = ski.getIndex(); assert (i >= 0); if (i != totalChannels - 1) { // Copy end one over it SelectionKeyImpl endChannel = channelArray[totalChannels-1]; channelArray[i] = endChannel; endChannel.setIndex(i); pollWrapper.release(i); PollArrayWrapper.replaceEntry(pollWrapper, totalChannels - 1, pollWrapper, i); } else { pollWrapper.release(i); } // Destroy the last one channelArray[totalChannels-1] = null; totalChannels--; pollWrapper.totalChannels--; ski.setIndex(-1); // Remove the key from keys and selectedKeys keys.remove(ski); selectedKeys.remove(ski); deregister((AbstractSelectionKey)ski); SelectableChannel selch = ski.channel(); if (!selch.isOpen() && !selch.isRegistered()) ((SelChImpl)selch).kill(); } }