org.jgroups.blocks.cs.NioBaseServer Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
package org.jgroups.blocks.cs;
import org.jgroups.Address;
import org.jgroups.annotations.ManagedAttribute;
import org.jgroups.annotations.ManagedOperation;
import org.jgroups.util.SocketFactory;
import org.jgroups.util.ThreadFactory;
import java.nio.channels.*;
import java.util.Iterator;
import java.util.Map;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* @author Bela Ban
* @since 3.6.5
*/
public abstract class NioBaseServer extends BaseServer {
protected Selector selector; // get notified about accepts, data ready to read/write etc
protected Thread acceptor; // the thread which calls select() in a loop
protected final Lock reg_lock=new ReentrantLock(); // for OP_CONNECT registrations
protected volatile boolean registration; // set to true after a registration; the acceptor sets it back to false
@ManagedAttribute(description="Max number of send buffers. Changing this value affects new buffers only",writable=true)
protected int max_send_buffers=5; // size of WriteBuffers send buffer array
@ManagedAttribute(description="Number of times select() was called")
protected int num_selects;
protected boolean copy_on_partial_write=true;
protected long reader_idle_time=20000;
protected NioBaseServer(ThreadFactory f, SocketFactory sf, int recv_buf_size) {
super(f, sf, recv_buf_size);
}
public int maxSendBuffers() {return max_send_buffers;}
public NioBaseServer maxSendBuffers(int num) {this.max_send_buffers=num; return this;}
public boolean selectorOpen() {return selector != null && selector.isOpen();}
public boolean acceptorRunning() {return acceptor != null && acceptor.isAlive();}
public int numSelects() {return num_selects;}
public boolean copyOnPartialWrite() {return copy_on_partial_write;}
public long readerIdleTime() {return reader_idle_time;}
public NioBaseServer readerIdleTime(long t) {reader_idle_time=t; return this;}
public NioBaseServer copyOnPartialWrite(boolean b) {
this.copy_on_partial_write=b;
synchronized(this) {
for(Connection c: conns.values()) {
NioConnection conn=(NioConnection)c;
conn.copyOnPartialWrite(b);
}
}
return this;
}
public synchronized int numPartialWrites() {
int retval=0;
for(Connection c: conns.values()) {
NioConnection conn=(NioConnection)c;
retval+=conn.numPartialWrites();
}
return retval;
}
/** Prints send and receive buffers for all connections */
@ManagedOperation(description="Prints the send and receive buffers")
public String printBuffers() {
StringBuilder sb=new StringBuilder("\n");
synchronized(this) {
for(Map.Entry entry: conns.entrySet()) {
NioConnection val=(NioConnection)entry.getValue();
sb.append(entry.getKey()).append(":\n ").append("recv_buf: ").append(val.recv_buf)
.append("\n send_buf: ").append(val.send_buf).append("\n");
}
}
return sb.toString();
}
protected SelectionKey register(SelectableChannel ch, int interest_ops, NioConnection conn) throws Exception {
reg_lock.lock();
try {
registration=true;
selector.wakeup(); // needed because registration will block until selector.select() returns
return ch.register(selector, interest_ops, conn);
}
finally {
reg_lock.unlock();
}
}
@Override
protected NioConnection createConnection(Address dest) throws Exception {
return new NioConnection(dest, this).copyOnPartialWrite(copy_on_partial_write);
}
protected void handleAccept(SelectionKey key) throws Exception {
;
}
protected void acceptorDone() {
}
protected class Acceptor implements Runnable {
public void run() {
Iterator it=null;
while(running.get() && doSelect()) {
try {
it=selector.selectedKeys().iterator();
}
catch(Throwable ex) {
continue;
}
while(it.hasNext()) {
SelectionKey key=it.next();
NioConnection conn=(NioConnection)key.attachment();
it.remove();
try {
if(!key.isValid())
continue;
// a key can be connectable *and* readable (https://issues.redhat.com/browse/JGRP-2531)
if(key.isConnectable()) {
SocketChannel ch=(SocketChannel)key.channel();
if(ch.finishConnect() || ch.isConnected()) {
conn.clearSelectionKey(SelectionKey.OP_CONNECT);
conn.connected(true);
}
}
else if(key.isAcceptable())
handleAccept(key);
else {
if (key.isReadable())
conn.receive();
if (key.isWritable())
conn.send();
}
}
catch(Throwable ex) {
closeConnection(conn);
}
}
}
acceptorDone();
}
protected boolean doSelect() {
try {
int num=selector.select();
num_selects++;
checkforPendingRegistrations();
if(num == 0) return true;
}
catch(ClosedSelectorException closed_ex) {
log.trace("selector was closed; acceptor terminating");
return false;
}
catch(Throwable t) {
log.warn("acceptor failure", t);
}
return true;
}
protected void checkforPendingRegistrations() {
if(registration) {
reg_lock.lock(); // mostly uncontended -> fast
try {
registration=false;
}
finally {
reg_lock.unlock();
}
}
}
}
}