/*
*============================================================================
* This library is free software; you can redistribute it and/or
* modify it under the terms of version 2.1 of the GNU Lesser General Public
* License as published by the Free Software Foundation.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*============================================================================
* Copyright (C) 2007 XenSource Inc.
*============================================================================
*/
package com.xensource.xenapi;
import java.util.Map;
import java.util.Set;
import java.util.Date;
import java.lang.ref.SoftReference;
import java.util.HashMap;
import java.util.HashSet;
import java.io.PrintWriter;
import java.io.StringWriter;
import org.apache.xmlrpc.XmlRpcException;
/**
* Asynchronous event registration and handling
*
* @author XenSource Inc.
*/
public class Event extends XenAPIObject {
/**
* The XenAPI reference to this object.
*/
protected final String ref;
private Event(String ref) {
this.ref = ref;
}
public String toWireString() {
return this.ref;
}
/**
* This code helps ensure there is only one
* Event instance per XenAPI reference.
*/
private static final Map<String,SoftReference<Event>> cache =
new HashMap<String,SoftReference<Event>>();
protected static synchronized Event getInstFromRef(String ref) {
if(Event.cache.containsKey(ref)) {
Event instance =
Event.cache.get(ref).get();
if(instance != null) {
return instance;
}
}
Event instance = new Event(ref);
Event.cache.put(ref, new SoftReference<Event>(instance));
return instance;
}
/**
* Represents all the fields in a Event
*/
public static class Record implements Types.Record{
public String toString() {
StringWriter writer = new StringWriter();
PrintWriter print = new PrintWriter(writer);
print.printf("%1$20s: %2$s\n", "id", this.id);
print.printf("%1$20s: %2$s\n", "timestamp", this.timestamp);
print.printf("%1$20s: %2$s\n", "clazz", this.clazz);
print.printf("%1$20s: %2$s\n", "operation", this.operation);
print.printf("%1$20s: %2$s\n", "ref", this.ref);
print.printf("%1$20s: %2$s\n", "objUuid", this.objUuid);
print.printf("%1$20s: %2$s\n", "snapshot", this.snapshot);
return writer.toString();
}
/**
* Convert a event.Record to a Map
*/
public Map<String,Object> toMap() {
Map<String,Object> map = new HashMap<String,Object>();
map.put("id", this.id == null ? 0 : this.id);
map.put("timestamp", this.timestamp == null ? new Date(0) : this.timestamp);
map.put("class", this.clazz == null ? "" : this.clazz);
map.put("operation", this.operation == null ? Types.EventOperation.UNRECOGNIZED : this.operation);
map.put("ref", this.ref == null ? "" : this.ref);
map.put("obj_uuid", this.objUuid == null ? "" : this.objUuid);
map.put("snapshot", this.snapshot);
return map;
}
/**
* An ID, monotonically increasing, and local to the current session
*/
public Long id;
/**
* The time at which the event occurred
*/
public Date timestamp;
/**
* The name of the class of the object that changed
*/
public String clazz;
/**
* The operation that was performed
*/
public Types.EventOperation operation;
/**
* A reference to the object that changed
*/
public String ref;
/**
* The uuid of the object that changed
*/
public String objUuid;
/**
* The record of the database object that was added, changed or deleted
* (the actual type will be VM.Record, VBD.Record or similar)
*/
public Object snapshot;
}
/**
* Registers this session with the event system. Specifying the empty list will register for all classes.
*
* @param classes register for events for the indicated classes
* @return Task
*/
public static Task registerAsync(Connection c, Set<String> classes) throws
Types.BadServerResponse,
XmlRpcException {
String method_call = "Async.event.register";
String session = c.getSessionReference();
Object[] method_params = {Marshalling.toXMLRPC(session), Marshalling.toXMLRPC(classes)};
Map response = c.dispatch(method_call, method_params);
if(response.get("Status").equals("Success")) {
Object result = response.get("Value");
return Types.toTask(result);
}
throw new Types.BadServerResponse(response);
}
/**
* Registers this session with the event system. Specifying the empty list will register for all classes.
*
* @param classes register for events for the indicated classes
*/
public static void register(Connection c, Set<String> classes) throws
Types.BadServerResponse,
XmlRpcException {
String method_call = "event.register";
String session = c.getSessionReference();
Object[] method_params = {Marshalling.toXMLRPC(session), Marshalling.toXMLRPC(classes)};
Map response = c.dispatch(method_call, method_params);
if(response.get("Status").equals("Success")) {
Object result = response.get("Value");
return;
}
throw new Types.BadServerResponse(response);
}
/**
* Unregisters this session with the event system
*
* @param classes remove this session's registration for the indicated classes
* @return Task
*/
public static Task unregisterAsync(Connection c, Set<String> classes) throws
Types.BadServerResponse,
XmlRpcException {
String method_call = "Async.event.unregister";
String session = c.getSessionReference();
Object[] method_params = {Marshalling.toXMLRPC(session), Marshalling.toXMLRPC(classes)};
Map response = c.dispatch(method_call, method_params);
if(response.get("Status").equals("Success")) {
Object result = response.get("Value");
return Types.toTask(result);
}
throw new Types.BadServerResponse(response);
}
/**
* Unregisters this session with the event system
*
* @param classes remove this session's registration for the indicated classes
*/
public static void unregister(Connection c, Set<String> classes) throws
Types.BadServerResponse,
XmlRpcException {
String method_call = "event.unregister";
String session = c.getSessionReference();
Object[] method_params = {Marshalling.toXMLRPC(session), Marshalling.toXMLRPC(classes)};
Map response = c.dispatch(method_call, method_params);
if(response.get("Status").equals("Success")) {
Object result = response.get("Value");
return;
}
throw new Types.BadServerResponse(response);
}
/**
* Blocking call which returns a (possibly empty) batch of events
*
* @return the batch of events
*/
public static Set<Event.Record> next(Connection c) throws
Types.BadServerResponse,
XmlRpcException,
Types.SessionNotRegistered,
Types.EventsLost {
String method_call = "event.next";
String session = c.getSessionReference();
Object[] method_params = {Marshalling.toXMLRPC(session)};
Map response = c.dispatch(method_call, method_params);
if(response.get("Status").equals("Success")) {
Object result = response.get("Value");
return Types.toSetOfEventRecord(result);
} else if(response.get("Status").equals("Failure")) {
Object[] error = (Object[]) response.get("ErrorDescription");
if(error[0].equals("SESSION_NOT_REGISTERED")) {
throw new Types.SessionNotRegistered((String) error[1]);
}
if(error[0].equals("EVENTS_LOST")) {
throw new Types.EventsLost();
}
}
throw new Types.BadServerResponse(response);
}
/**
* Return the ID of the next event to be generated by the system
*
* @return the event ID
*/
public static Long getCurrentId(Connection c) throws
Types.BadServerResponse,
XmlRpcException {
String method_call = "event.get_current_id";
String session = c.getSessionReference();
Object[] method_params = {Marshalling.toXMLRPC(session)};
Map response = c.dispatch(method_call, method_params);
if(response.get("Status").equals("Success")) {
Object result = response.get("Value");
return Types.toLong(result);
}
throw new Types.BadServerResponse(response);
}
}