org.jgroups.stack.ProtocolStack Maven / Gradle / Ivy
package org.jgroups.stack;
import org.jgroups.Address;
import org.jgroups.Event;
import org.jgroups.Global;
import org.jgroups.JChannel;
import org.jgroups.annotations.Property;
import org.jgroups.conf.ClassConfigurator;
import org.jgroups.conf.PropertyConverter;
import org.jgroups.conf.ProtocolConfiguration;
import org.jgroups.protocols.TP;
import org.jgroups.util.AsciiString;
import org.jgroups.util.MessageBatch;
import org.jgroups.util.Tuple;
import org.jgroups.util.Util;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.*;
import java.util.Map.Entry;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
* A ProtocolStack manages a number of protocols layered above each other. It
* creates all protocol classes, initializes them and, when ready, starts all of
* them, beginning with the bottom most protocol. It also dispatches messages
* received from the stack to registered objects (e.g. channel, GMP) and sends
* messages sent by those objects down the stack.
*
* The ProtocolStack makes use of the Configurator to setup and initialize
* stacks, and to destroy them again when not needed anymore
*
* @author Bela Ban
*/
public class ProtocolStack extends Protocol {
public static final int ABOVE = 1; // used by insertProtocol()
public static final int BELOW = 2; // used by insertProtocol()
protected static final String max_list_print_size="max-list-print-size";
/**
* Holds the shared transports, keyed by 'TP.singleton_name'. The values are the transport and the use count for
* init() (decremented by destroy()) and start() (decremented by stop()
*/
protected static final ConcurrentMap> singleton_transports=new ConcurrentHashMap<>();
protected Protocol top_prot;
protected Protocol bottom_prot;
protected JChannel channel;
protected volatile boolean stopped=true;
public ProtocolStack topProtocol(Protocol top) {this.top_prot=top; return this;}
public ProtocolStack bottomProtocol(Protocol bottom) {this.bottom_prot=bottom; return this;}
protected final DiagnosticsHandler.ProbeHandler props_handler=new DiagnosticsHandler.ProbeHandler() {
public Map handleProbe(String... keys) {
for(String key: keys) {
if(key.equals("props")) {
String tmp=printProtocolSpec(true);
HashMap map=new HashMap<>(1);
map.put("props", tmp);
return map;
}
if(key.startsWith(max_list_print_size)) {
int index=key.indexOf("=");
if(index >= 0) {
Util.MAX_LIST_PRINT_SIZE=Integer.valueOf(key.substring(index+1));
}
HashMap map=new HashMap<>(1);
map.put(max_list_print_size, String.valueOf(Util.MAX_LIST_PRINT_SIZE));
return map;
}
if(key.startsWith("print-protocols")) {
List prots=getProtocols();
Collections.reverse(prots);
StringBuilder sb=new StringBuilder();
for(Protocol prot: prots)
sb.append(prot.getName()).append("\n");
HashMap map=new HashMap<>(1);
map.put("protocols", sb.toString());
return map;
}
if(key.startsWith("remove-protocol")) {
key=key.substring("remove-protocol".length());
int index=key.indexOf("=");
if(index != -1) {
String prot_name=key.substring(index +1);
if(prot_name != null && !prot_name.isEmpty()) {
try {
Protocol removed=removeProtocol(prot_name);
if(removed != null)
log.debug("removed protocol " + prot_name + " from stack");
}
catch(Exception e) {
log.error("failed removing protocol " + prot_name, e);
}
}
}
}
if(key.startsWith("insert-protocol")) {
key=key.substring("insert-protocol".length()+1);
int index=key.indexOf("=");
if(index == -1) break;
// 1. name of the protocol to be inserted
String prot_name=key.substring(0, index).trim();
if(findProtocol(prot_name) != null) {
log.error("Protocol %s cannot be inserted as it is already present", prot_name);
break;
}
Protocol prot=null;
try {
prot=createProtocol(prot_name);
//prot.init();
//prot.start();
}
catch(Exception e) {
log.error("failed creating an instance of " + prot_name, e);
break;
}
key=key.substring(index+1);
index=key.indexOf('=');
if(index == -1) {
log.error("= missing in insert-protocol command");
break;
}
// 2. "above" or "below"
String tmp=key.substring(0, index);
if(!tmp.equalsIgnoreCase("above") && !tmp.equalsIgnoreCase("below")) {
log.error("Missing \"above\" or \"below\" in insert-protocol command");
break;
}
key=key.substring(index+1);
String neighbor_prot=key.trim();
Protocol neighbor=findProtocol(neighbor_prot);
if(neighbor == null) {
log.error("Neighbor protocol " + neighbor_prot + " not found in stack");
break;
}
int position=tmp.equalsIgnoreCase("above")? ABOVE : BELOW;
try {
insertProtocol(prot, position, neighbor.getClass());
}
catch(Exception e) {
log.error("failed inserting protocol " + prot_name + " " + tmp + " " + neighbor_prot, e);
}
try {
prot.init();
prot.start();
}
catch(Exception e) {
log.error("failed creating an instance of " + prot_name, e);
}
}
}
return null;
}
public String[] supportedKeys() {
return new String[]{"props", max_list_print_size + "[=number]", "print-protocols", "\nremove-protocol=",
"\ninsert-protocol==above | below="};
}
};
public ProtocolStack(JChannel channel) throws Exception {
this.channel=channel;
Class tmp=ClassConfigurator.class; // load this class, trigger init()
tmp.newInstance();
}
/** Used for programmatic creation of ProtocolStack */
public ProtocolStack() {
}
public JChannel getChannel() {return channel;}
public ProtocolStack setChannel(JChannel ch) {
this.channel=ch; return this;
}
/** Returns all protocols in a list, from top to bottom. These are not copies of protocols,
so modifications will affect the actual instances ! */
public List getProtocols() {
List v=new ArrayList<>(15);
Protocol p=top_prot;
while(p != null) {
v.add(p);
p=p.getDownProtocol();
}
return v;
}
public List copyProtocols(ProtocolStack targetStack) throws IllegalAccessException, InstantiationException {
List list=getProtocols();
List retval=new ArrayList<>(list.size());
for(Protocol prot: list) {
Protocol new_prot=prot.getClass().newInstance();
new_prot.setProtocolStack(targetStack);
retval.add(new_prot);
for(Class clazz=prot.getClass(); clazz != null; clazz=clazz.getSuperclass()) {
// copy all fields marked with @Property
Field[] fields=clazz.getDeclaredFields();
for(Field field: fields) {
if(field.isAnnotationPresent(Property.class)) {
Object value=Util.getField(field, prot);
Util.setField(field, new_prot, value);
}
}
// copy all setters marked with @Property
Method[] methods=clazz.getDeclaredMethods();
for(Method method: methods) {
String methodName=method.getName();
if(method.isAnnotationPresent(Property.class) && Configurator.isSetPropertyMethod(method)) {
Property annotation=method.getAnnotation(Property.class);
List possible_names=new LinkedList<>();
if(annotation.name() != null)
possible_names.add(annotation.name());
possible_names.add(Util.methodNameToAttributeName(methodName));
Field field=Util.findField(prot, possible_names);
if(field != null) {
Object value=Util.getField(field, prot);
Util.setField(field, new_prot, value);
}
}
}
}
}
return retval;
}
/** Returns the bottom most protocol */
public TP getTransport() {
return (TP)getBottomProtocol();
}
public static ConcurrentMap> getSingletonTransports() {
return singleton_transports;
}
/**
*
* @return Map>
*/
public Map dumpStats() {
Protocol p;
Map retval=new HashMap<>(), tmp;
String prot_name;
p=top_prot;
while(p != null) {
prot_name=p.getName();
tmp=p.dumpStats();
if(prot_name != null && tmp != null)
retval.put(prot_name, tmp);
p=p.getDownProtocol();
}
return retval;
}
public Map dumpStats(String protocol_name) {
return dumpStats(protocol_name, null);
}
public Map dumpStats(String protocol_name, List attrs) {
Protocol prot=findProtocol(protocol_name);
if(prot == null)
return null;
Map retval=new HashMap<>(), tmp;
tmp=prot.dumpStats();
if(tmp != null) {
if(attrs != null && !attrs.isEmpty()) {
// weed out attrs not in list
for(Iterator it=tmp.keySet().iterator(); it.hasNext();) {
String attrname=it.next();
boolean found=false;
for(String attr: attrs) {
if(attrname.startsWith(attr)) {
found=true;
break; // found
}
}
if(!found)
it.remove();
}
}
retval.put(protocol_name, tmp);
}
return retval;
}
/**
* Prints the names of the protocols, from the bottom to top. If include_properties is true,
* the properties for each protocol will also be printed.
*/
public String printProtocolSpec(boolean include_properties) {
StringBuilder sb=new StringBuilder();
List protocols=getProtocols();
if(protocols == null || protocols.isEmpty()) return null;
boolean first_colon_printed=false;
Collections.reverse(protocols);
for(Protocol prot: protocols) {
String prot_name=prot.getClass().getName();
int index=prot_name.indexOf(Global.PREFIX);
if(index >= 0)
prot_name=prot_name.substring(Global.PREFIX.length());
if(first_colon_printed) {
sb.append(":");
}
else {
first_colon_printed=true;
}
sb.append(prot_name);
if(include_properties) {
Map tmp=getProps(prot);
if(!tmp.isEmpty()) {
boolean printed=false;
sb.append("(");
for(Map.Entry entry: tmp.entrySet()) {
if(printed) {
sb.append(";");
}
else {
printed=true;
}
sb.append(entry.getKey()).append("=").append(entry.getValue());
}
sb.append(")\n");
}
}
}
return sb.toString();
}
public String printProtocolSpecAsXML() {
StringBuilder sb=new StringBuilder();
Protocol prot=bottom_prot;
int len, max_len=30;
sb.append("\n");
while(prot != null) {
String prot_name=prot.getName();
if(prot_name != null) {
if("ProtocolStack".equals(prot_name))
break;
sb.append(" <").append(prot_name).append(" ");
Map tmpProps=getProps(prot);
if(tmpProps != null) {
len=prot_name.length();
String s;
for(Iterator> it=tmpProps.entrySet().iterator();it.hasNext();) {
Entry entry=it.next();
s=entry.getKey() + "=\"" + entry.getValue() + "\" ";
if(len + s.length() > max_len) {
sb.append("\n ");
len=8;
}
sb.append(s);
len+=s.length();
}
}
sb.append("/>\n");
prot=prot.getUpProtocol();
}
}
sb.append(" ");
return sb.toString();
}
public String printProtocolSpecAsPlainString() {
return printProtocolSpecAsPlainString(false);
}
private String printProtocolSpecAsPlainString(boolean print_props) {
StringBuilder sb=new StringBuilder();
List protocols=getProtocols();
if(protocols == null) return null;
Collections.reverse(protocols);
for(Protocol prot: protocols) {
sb.append(prot.getClass().getName()).append("\n");
if(print_props) {
Map tmp=getProps(prot);
for(Map.Entry entry: tmp.entrySet()) {
sb.append(" ").append(entry.getKey()).append("=").append(entry.getValue()).append("\n");
}
}
}
return sb.toString();
}
private static Map getProps(Protocol prot) {
Map retval=new HashMap<>();
for(Class clazz=prot.getClass(); clazz != null; clazz=clazz.getSuperclass()) {
// copy all fields marked with @Property
Field[] fields=clazz.getDeclaredFields();
Property annotation;
for(Field field: fields) {
if(field.isAnnotationPresent(Property.class)) {
Object value=Util.getField(field, prot);
if(value != null) {
annotation=field.getAnnotation(Property.class);
Class conv_class=annotation.converter();
PropertyConverter conv=null;
try {
conv=(PropertyConverter)conv_class.newInstance();
}
catch(Exception e) {
}
String tmp=conv != null? conv.toString(value) : value.toString();
retval.put(field.getName(), tmp);
}
}
}
// copy all setters marked with @Property
Method[] methods=clazz.getDeclaredMethods();
for(Method method: methods) {
String methodName=method.getName();
if(method.isAnnotationPresent(Property.class) && Configurator.isSetPropertyMethod(method)) {
annotation=method.getAnnotation(Property.class);
List possible_names=new LinkedList<>();
if(annotation.name() != null)
possible_names.add(annotation.name());
possible_names.add(Util.methodNameToAttributeName(methodName));
Field field=Util.findField(prot, possible_names);
if(field != null) {
Object value=Util.getField(field, prot);
if(value != null) {
Class conv_class=annotation.converter();
PropertyConverter conv=null;
try {
conv=(PropertyConverter)conv_class.newInstance();
}
catch(Exception e) {
}
String tmp=conv != null? conv.toString(value) : value.toString();
retval.put(field.getName(), tmp);
}
}
}
}
}
return retval;
}
public void setup(List configs) throws Exception {
if(top_prot == null) {
top_prot=new Configurator(this).setupProtocolStack(configs);
top_prot.setUpProtocol(this);
this.setDownProtocol(top_prot);
bottom_prot=getBottomProtocol();
initProtocolStack();
}
}
public void setup(ProtocolStack stack) throws Exception {
if(top_prot == null) {
top_prot=new Configurator(this).setupProtocolStack(stack);
top_prot.setUpProtocol(this);
this.setDownProtocol(top_prot);
bottom_prot=getBottomProtocol();
initProtocolStack();
}
}
/**
* Adds a protocol at the tail of the protocol list
* @param prot
* @return
* @since 2.11
*/
public ProtocolStack addProtocol(Protocol prot) {
if(prot == null)
return this;
prot.setProtocolStack(this);
prot.setUpProtocol(this);
if(bottom_prot == null) {
top_prot=bottom_prot=prot;
return this;
}
prot.setDownProtocol(top_prot);
prot.getDownProtocol().setUpProtocol(prot);
top_prot=prot;
return this;
}
/**
* Adds a list of protocols
* @param prots
* @return
* @since 2.11
*/
public ProtocolStack addProtocols(Protocol ... prots) {
if(prots != null) {
for(Protocol prot: prots)
addProtocol(prot);
}
return this;
}
/**
* Adds a list of protocols
* @param prots
* @return
* @since 2.1
*/
public ProtocolStack addProtocols(List prots) {
if(prots != null) {
for(Protocol prot: prots)
addProtocol(prot);
}
return this;
}
/**
* Inserts an already created (and initialized) protocol into the protocol list. Sets the links
* to the protocols above and below correctly and adjusts the linked list of protocols accordingly.
* Note that this method may change the value of top_prot or bottom_prot.
* @param prot The protocol to be inserted. Before insertion, a sanity check will ensure that none
* of the existing protocols have the same name as the new protocol.
* @param position Where to place the protocol with respect to the neighbor_prot (ABOVE, BELOW)
* @param neighbor_prot The name of the neighbor protocol. An exception will be thrown if this name
* is not found
* @exception Exception Will be thrown when the new protocol cannot be created, or inserted.
*/
public void insertProtocol(Protocol prot, int position, String neighbor_prot) throws Exception {
if(neighbor_prot == null) throw new IllegalArgumentException("neighbor_prot is null");
if(position != ProtocolStack.ABOVE && position != ProtocolStack.BELOW)
throw new IllegalArgumentException("position has to be ABOVE or BELOW");
Protocol neighbor=findProtocol(neighbor_prot);
if(neighbor == null)
throw new IllegalArgumentException("protocol " + neighbor_prot + " not found in " + printProtocolSpec(false));
if(position == ProtocolStack.BELOW && neighbor instanceof TP)
throw new IllegalArgumentException("Cannot insert protocol " + prot.getName() + " below transport protocol");
insertProtocolInStack(prot, neighbor, position);
}
public void insertProtocolInStack(Protocol prot, Protocol neighbor, int position) {
// connect to the protocol layer below and above
if(position == ProtocolStack.BELOW) {
prot.setUpProtocol(neighbor);
Protocol below=neighbor.getDownProtocol();
prot.setDownProtocol(below);
if(below != null)
below.setUpProtocol(prot);
neighbor.setDownProtocol(prot);
}
else { // ABOVE is default
Protocol above=neighbor.getUpProtocol();
checkAndSwitchTop(neighbor, prot);
prot.setUpProtocol(above);
if(above != null)
above.setDownProtocol(prot);
prot.setDownProtocol(neighbor);
neighbor.setUpProtocol(prot);
}
}
private void checkAndSwitchTop(Protocol oldTop, Protocol newTop){
if(oldTop == top_prot) {
top_prot = newTop;
top_prot.setUpProtocol(this);
}
}
public void insertProtocol(Protocol prot, int position, Class neighbor_prot) throws Exception {
if(neighbor_prot == null) throw new IllegalArgumentException("neighbor_prot is null");
if(position != ProtocolStack.ABOVE && position != ProtocolStack.BELOW)
throw new IllegalArgumentException("position has to be ABOVE or BELOW");
Protocol neighbor=findProtocol(neighbor_prot);
if(neighbor == null)
throw new IllegalArgumentException("protocol \"" + neighbor_prot + "\" not found in " + stack.printProtocolSpec(false));
if(position == ProtocolStack.BELOW && neighbor instanceof TP)
throw new IllegalArgumentException("protocol \"" + prot + "\" cannot be inserted below the transport protocol (" +
neighbor + ")");
insertProtocolInStack(prot, neighbor, position);
}
public void insertProtocol(Protocol prot, int position, Class ... neighbor_prots) throws Exception {
if(neighbor_prots == null) throw new IllegalArgumentException("neighbor_prots is null");
if(position != ProtocolStack.ABOVE && position != ProtocolStack.BELOW)
throw new IllegalArgumentException("position has to be ABOVE or BELOW");
Protocol neighbor=findProtocol(neighbor_prots);
if(neighbor == null)
throw new IllegalArgumentException("protocol \"" + Arrays.toString(neighbor_prots) + "\" not found in " + stack.printProtocolSpec(false));
insertProtocolInStack(prot, neighbor, position);
}
public void insertProtocolAtTop(Protocol prot) {
if(prot == null)
throw new IllegalArgumentException("prot needs to be non-null");
// check if prot already exists (we cannot have more than 1 protocol of a given class)
Class clazz=prot.getClass();
Protocol existing_instance=findProtocol(clazz);
if(existing_instance != null)
return;
top_prot.up_prot=prot;
prot.down_prot=top_prot;
prot.up_prot=this;
top_prot=prot;
log.debug("inserted " + prot + " at the top of the stack");
}
/**
* Removes a protocol from the stack. Stops the protocol and readjusts the linked lists of
* protocols.
* @param prot_name The name of the protocol. Since all protocol names in a stack have to be unique
* (otherwise the stack won't be created), the name refers to just 1 protocol.
* @exception Exception Thrown if the protocol cannot be stopped correctly.
*/
public Protocol removeProtocol(String prot_name) {
if(prot_name == null) return null;
return removeProtocol(findProtocol(prot_name));
}
public void removeProtocols(String ... protocols) {
for(String protocol: protocols)
removeProtocol(protocol);
}
public Protocol removeProtocol(Class ... protocols) {
Protocol retval=null;
if(protocols != null)
for(Class cl: protocols) {
Protocol tmp=removeProtocol(cl);
if(tmp != null)
retval=tmp;
}
return retval;
}
public Protocol removeProtocol(Class prot) {
if(prot == null)
return null;
return removeProtocol(findProtocol(prot));
}
public Protocol removeProtocol(Protocol prot) {
if(prot == null) return null;
Protocol above=prot.getUpProtocol(), below=prot.getDownProtocol();
checkAndSwitchTop(prot, below);
if(above != null)
above.setDownProtocol(below);
if(below != null)
below.setUpProtocol(above);
prot.setUpProtocol(null);
prot.setDownProtocol(null);
try {
prot.stop();
}
catch(Throwable t) {
log.error("failed stopping " + prot.getName() + ": " + t);
}
try {
prot.destroy();
}
catch(Throwable t) {
log.error("failed destroying " + prot.getName() + ": " + t);
}
return prot;
}
/** Returns a given protocol or null if not found */
public Protocol findProtocol(String name) {
Protocol tmp=top_prot;
String prot_name;
while(tmp != null) {
prot_name=tmp.getName();
if(prot_name != null && prot_name.equals(name))
return tmp;
tmp=tmp.getDownProtocol();
}
return null;
}
public Protocol getBottomProtocol() {
Protocol curr_prot=this;
while(curr_prot != null && curr_prot.getDownProtocol() !=null) {
curr_prot=curr_prot.getDownProtocol();
}
return curr_prot;
}
public Protocol getTopProtocol() {
return top_prot;
}
public Protocol findProtocol(Class clazz) {
Protocol tmp=top_prot;
while(tmp != null) {
Class protClass=tmp.getClass();
if(clazz.isAssignableFrom(protClass)){
return tmp;
}
tmp=tmp.getDownProtocol();
}
return null;
}
/**
* Finds the first protocol of a list and returns it. Returns null if no protocol can be found
* @param classes A list of protocol classes to find
* @return Protocol The protocol found
*/
public Protocol findProtocol(Class ... classes) {
for(Class clazz: classes) {
Protocol prot=findProtocol(clazz);
if(prot != null)
return prot;
}
return null;
}
/**
* Replaces one protocol instance with another. Should be done before the stack is connected
* @param existing_prot
* @param new_prot
*/
public void replaceProtocol(Protocol existing_prot, Protocol new_prot) throws Exception {
Protocol up_neighbor=existing_prot.getUpProtocol(), down_neighbor=existing_prot.getDownProtocol();
new_prot.setUpProtocol(existing_prot.getUpProtocol());
new_prot.setDownProtocol(existing_prot.getDownProtocol());
up_neighbor.setDownProtocol(new_prot);
if(down_neighbor != null)
down_neighbor.setUpProtocol(new_prot);
existing_prot.setDownProtocol(null);
existing_prot.setUpProtocol(null);
existing_prot.stop();
existing_prot.destroy();
if(new_prot.getUpProtocol() == this)
top_prot=new_prot;
new_prot.init();
}
protected Protocol createProtocol(String classname) throws Exception {
String defaultProtocolName=ProtocolConfiguration.protocol_prefix + '.' + classname;
Class clazz=null;
try {
clazz=Util.loadClass(defaultProtocolName, getClass());
}
catch(ClassNotFoundException e) {
}
if(clazz == null) {
try {
clazz=Util.loadClass(classname, getClass());
}
catch(ClassNotFoundException e) {
}
if(clazz == null) {
throw new Exception("unable to load class for protocol " + classname + " (either as an absolute - "
+ classname + " - or relative - " + defaultProtocolName + " - package name)");
}
}
Protocol retval=(Protocol)clazz.newInstance();
if(retval == null)
throw new Exception("creation of instance for protocol " + classname + "failed");
retval.setProtocolStack(this);
return retval;
}
public void init() throws Exception {
List protocols=getProtocols();
Collections.reverse(protocols);
top_prot=Configurator.connectProtocols(protocols);
top_prot.setUpProtocol(this);
this.setDownProtocol(top_prot);
bottom_prot=getBottomProtocol();
Configurator.setDefaultValues(protocols);
initProtocolStack();
}
public void initProtocolStack() throws Exception {
List protocols = getProtocols();
Collections.reverse(protocols);
for(Protocol prot: protocols) {
if(prot.getProtocolStack() == null)
prot.setProtocolStack(this);
if(prot instanceof TP) {
TP transport=(TP)prot;
if(transport.isSingleton()) {
String singleton_name=transport.getSingletonName();
synchronized(singleton_transports) {
Tuple val=singleton_transports.get(singleton_name);
if(val == null)
singleton_transports.put(singleton_name, new Tuple<>(transport,new RefCounter((short)1, (short)0)));
else {
RefCounter counter=val.getVal2();
short num_inits=counter.incrementInitCount();
if(num_inits >= 1)
continue;
}
prot.init(); // if shared TP, call init() with lock : https://issues.jboss.org/browse/JGRP-1887
continue;
}
}
}
prot.init();
}
}
public void destroy() {
if(top_prot != null) {
for(Protocol prot: getProtocols()) {
if(prot instanceof TP) {
TP transport=(TP)prot;
if(transport.isSingleton()) {
String singleton_name=transport.getSingletonName();
synchronized(singleton_transports) {
Tuple val=singleton_transports.get(singleton_name);
if(val != null) {
ProtocolStack.RefCounter counter=val.getVal2();
short num_inits=counter.decrementInitCount();
if(num_inits >= 1) {
continue;
}
else
singleton_transports.remove(singleton_name);
}
}
}
}
prot.destroy();
}
/*
*Do not null top_prot reference since we need recreation of channel properties (JChannel#getProperties)
*during channel recreation, especially if those properties were modified after channel was created.
*We modify channel properties after channel creation in some tests for example
*
*/
//top_prot=null;
}
}
/**
* Start all layers. The {@link Protocol#start()} method is called in each protocol,
* from top to bottom.
* Each layer can perform some initialization, e.g. create a multicast socket
*/
public void startStack(String cluster, Address local_addr) throws Exception {
if(stopped == false) return;
final AsciiString cluster_name=new AsciiString(cluster);
Protocol above_prot=null;
for(final Protocol prot: getProtocols()) {
if(prot instanceof TP) {
String singleton_name=((TP)prot).getSingletonName();
TP transport=(TP)prot;
if(transport.isSingleton() && cluster_name != null) {
final Map up_prots=transport.getUpProtocols();
synchronized(singleton_transports) {
synchronized(up_prots) {
Set keys=up_prots.keySet();
if(keys.contains(cluster_name))
throw new IllegalStateException("cluster '" + cluster_name + "' is already connected to singleton " +
"transport: " + keys);
for(Iterator> it=up_prots.entrySet().iterator(); it.hasNext();) {
Map.Entry entry=it.next();
Protocol tmp=entry.getValue();
if(tmp == above_prot) {
it.remove();
}
}
if(above_prot != null) {
TP.ProtocolAdapter ad=new TP.ProtocolAdapter(new AsciiString(cluster_name), local_addr, prot.getId(),
above_prot, prot,
transport.getThreadNamingPattern());
ad.setProtocolStack(above_prot.getProtocolStack());
above_prot.setDownProtocol(ad);
up_prots.put(cluster_name, ad);
}
}
Tuple val=singleton_transports.get(singleton_name);
if(val != null) {
ProtocolStack.RefCounter counter=val.getVal2();
short num_starts=counter.incrementStartCount();
if(num_starts >= 1) {
continue;
}
else {
try {
prot.start();
}
catch(Exception ex) {
counter.decrementStartCount();
up_prots.remove(cluster_name);
throw ex;
}
above_prot=prot;
continue;
}
}
}
}
}
prot.start();
above_prot=prot;
}
TP transport=getTransport();
transport.registerProbeHandler(props_handler);
stopped=false;
}
/**
* Iterates through all the protocols from top to bottom and does the following:
*
* - Waits until all messages in the down queue have been flushed (ie., size is 0)
*
- Calls stop() on the protocol
*
*/
public void stopStack(String cluster) {
if(stopped) return;
final AsciiString cluster_name=new AsciiString(cluster);
for(final Protocol prot: getProtocols()) {
if(prot instanceof TP) {
TP transport=(TP)prot;
if(transport.isSingleton()) {
String singleton_name=transport.getSingletonName();
final Map up_prots=transport.getUpProtocols();
synchronized(up_prots) {
Protocol adapter=up_prots.remove(cluster_name);
if(adapter != null) {
Protocol neighbor_above=adapter.getUpProtocol();
if(neighbor_above != null)
neighbor_above.setDownProtocol(transport);
}
}
synchronized(singleton_transports) {
Tuple val=singleton_transports.get(singleton_name);
if(val != null) {
ProtocolStack.RefCounter counter=val.getVal2();
short num_starts=counter.decrementStartCount();
if(num_starts > 0) {
continue; // don't call TP.stop() if we still have references to the transport
}
//else
// singletons.remove(singleton_name); // do the removal in destroyProtocolStack()
}
}
}
}
prot.stop();
}
TP transport=getTransport();
transport.unregisterProbeHandler(props_handler);
stopped=true;
}
/*--------------------------- Protocol functionality ------------------------------*/
public String getName() {return "ProtocolStack";}
public Object up(Event evt) {
return channel.up(evt);
}
public void up(MessageBatch batch) {
channel.up(batch);
}
public Object down(Event evt) {
if(top_prot != null)
return top_prot.down(evt);
return null;
}
/**
* Keeps track of the number os times init()/destroy() and start()/stop have been called. The variables
* init_count and start_count are incremented or decremented accoordingly. Note that this class is not synchronized
*/
public static class RefCounter {
private short init_count=0;
private short start_count=0;
public RefCounter(short init_count, short start_count) {
this.init_count=init_count;
this.start_count=start_count;
}
public short getInitCount() {
return init_count;
}
public short getStartCount() {
return start_count;
}
/**
* Increments init_count, returns the old value before incr
* @return
*/
public short incrementInitCount(){
return init_count++;
}
public short decrementInitCount() {
init_count=(short)Math.max(init_count -1, 0);
return init_count;
}
public short decrementStartCount() {
start_count=(short)Math.max(start_count -1, 0);
return start_count;
}
public short incrementStartCount() {
return start_count++;
}
public String toString() {
return "init_count=" + init_count + ", start_count=" + start_count;
}
}
}