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This commit is contained in:
Edward Capriolo
2015-01-17 18:21:57 -05:00
parent 4506fe4a79
commit 17f1ad6f4f
14 changed files with 811 additions and 725 deletions
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117
src/main/java/com/google/code/gossip/GossipSettings.java
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@ -7,58 +7,67 @@ package com.google.code.gossip;
*/ */
public class GossipSettings { public class GossipSettings {
/** Time between gossip'ing in ms. Default is 1 second. */ /** Time between gossip'ing in ms. Default is 1 second. */
private int _gossipInterval = 1000; private int _gossipInterval = 1000;
/** Time between cleanups in ms. Default is 10 seconds. */ /** Time between cleanups in ms. Default is 10 seconds. */
private int _cleanupInterval = 10000; private int _cleanupInterval = 10000;
/** /**
* Construct GossipSettings with default settings. * Construct GossipSettings with default settings.
*/ */
public GossipSettings() {} public GossipSettings() {
}
/**
* Construct GossipSettings with given settings. /**
* @param gossipInterval The gossip interval in ms. * Construct GossipSettings with given settings.
* @param cleanupInterval The cleanup interval in ms. *
*/ * @param gossipInterval
public GossipSettings(int gossipInterval, int cleanupInterval) { * The gossip interval in ms.
_gossipInterval = gossipInterval; * @param cleanupInterval
_cleanupInterval = cleanupInterval; * The cleanup interval in ms.
} */
public GossipSettings(int gossipInterval, int cleanupInterval) {
/** _gossipInterval = gossipInterval;
* Set the gossip interval. _cleanupInterval = cleanupInterval;
* This is the time between a gossip message is send. }
* @param gossipInterval The gossip interval in ms.
*/ /**
public void setGossipTimeout(int gossipInterval) { * Set the gossip interval. This is the time between a gossip message is send.
_gossipInterval = gossipInterval; *
} * @param gossipInterval
* The gossip interval in ms.
/** */
* Set the cleanup interval. public void setGossipTimeout(int gossipInterval) {
* This is the time between the last heartbeat received from a member and when it will be marked as dead. _gossipInterval = gossipInterval;
* @param cleanupInterval The cleanup interval in ms. }
*/
public void setCleanupInterval(int cleanupInterval) { /**
_cleanupInterval = cleanupInterval; * Set the cleanup interval. This is the time between the last heartbeat received from a member
} * and when it will be marked as dead.
*
/** * @param cleanupInterval
* Get the gossip interval. * The cleanup interval in ms.
* @return The gossip interval in ms. */
*/ public void setCleanupInterval(int cleanupInterval) {
public int getGossipInterval() { _cleanupInterval = cleanupInterval;
return _gossipInterval; }
}
/**
/** * Get the gossip interval.
* Get the clean interval. *
* @return The cleanup interval. * @return The gossip interval in ms.
*/ */
public int getCleanupInterval() { public int getGossipInterval() {
return _cleanupInterval; return _gossipInterval;
} }
/**
* Get the clean interval.
*
* @return The cleanup interval.
*/
public int getCleanupInterval() {
return _cleanupInterval;
}
} }

86
src/main/java/com/google/code/gossip/GossipTimeoutTimer.java
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@ -6,56 +6,58 @@ import javax.management.NotificationListener;
import javax.management.timer.Timer; import javax.management.timer.Timer;
/** /**
* This object represents a timer for a gossip member. * This object represents a timer for a gossip member. When the timer has elapsed without being
* When the timer has elapsed without being reset in the meantime, it will inform the GossipService about this * reset in the meantime, it will inform the GossipService about this who in turn will put the
* who in turn will put the gossip member on the dead list, because it is apparantly not alive anymore. * gossip member on the dead list, because it is apparantly not alive anymore.
* *
* @author joshclemm, harmenw * @author joshclemm, harmenw
*/ */
public class GossipTimeoutTimer extends Timer { public class GossipTimeoutTimer extends Timer {
/** The amount of time this timer waits before generating a wake-up event. */ /** The amount of time this timer waits before generating a wake-up event. */
private long _sleepTime; private long _sleepTime;
/** The gossip member this timer is for. */ /** The gossip member this timer is for. */
private LocalGossipMember _source; private LocalGossipMember _source;
/** /**
* Constructor. * Constructor. Creates a reset-able timer that wakes up after millisecondsSleepTime.
* Creates a reset-able timer that wakes up after millisecondsSleepTime. *
* @param millisecondsSleepTime The time for this timer to wait before an event. * @param millisecondsSleepTime
* @param service * The time for this timer to wait before an event.
* @param member * @param service
*/ * @param member
public GossipTimeoutTimer(long millisecondsSleepTime, NotificationListener notificationListener, LocalGossipMember member) { */
super(); public GossipTimeoutTimer(long millisecondsSleepTime, NotificationListener notificationListener,
_sleepTime = millisecondsSleepTime; LocalGossipMember member) {
_source = member; super();
addNotificationListener(notificationListener, null, null); _sleepTime = millisecondsSleepTime;
} _source = member;
addNotificationListener(notificationListener, null, null);
}
/** /**
* @see javax.management.timer.Timer#start() * @see javax.management.timer.Timer#start()
*/ */
public void start() { public void start() {
this.reset(); this.reset();
super.start(); super.start();
} }
/** /**
* Resets timer to start counting down from original time. * Resets timer to start counting down from original time.
*/ */
public void reset() { public void reset() {
removeAllNotifications(); removeAllNotifications();
setWakeupTime(_sleepTime); setWakeupTime(_sleepTime);
} }
/** /**
* Adds a new wake-up time for this timer. * Adds a new wake-up time for this timer.
* @param milliseconds *
*/ * @param milliseconds
private void setWakeupTime(long milliseconds) { */
addNotification("type", "message", _source, new Date(System.currentTimeMillis()+milliseconds)); private void setWakeupTime(long milliseconds) {
} addNotification("type", "message", _source, new Date(System.currentTimeMillis() + milliseconds));
}
} }

65
src/main/java/com/google/code/gossip/LocalGossipMember.java
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@ -3,40 +3,47 @@ package com.google.code.gossip;
import javax.management.NotificationListener; import javax.management.NotificationListener;
/** /**
* This object represent a gossip member with the properties known locally. * This object represent a gossip member with the properties known locally. These objects are stored
* These objects are stored in the local list of gossip member.s * in the local list of gossip member.s
* *
* @author harmenw * @author harmenw
*/ */
public class LocalGossipMember extends GossipMember { public class LocalGossipMember extends GossipMember {
/** The timeout timer for this gossip member. */ /** The timeout timer for this gossip member. */
private transient GossipTimeoutTimer timeoutTimer; private transient GossipTimeoutTimer timeoutTimer;
/** /**
* Constructor. * Constructor.
* @param host The hostname or IP address. *
* @param port The port number. * @param host
* @param heartbeat The current heartbeat. * The hostname or IP address.
* @param gossipService The GossipService object. * @param port
* @param cleanupTimeout The cleanup timeout for this gossip member. * The port number.
*/ * @param heartbeat
public LocalGossipMember(String hostname, int port, String id, int heartbeat, NotificationListener notificationListener, int cleanupTimeout) { * The current heartbeat.
super(hostname, port, id, heartbeat); * @param gossipService
* The GossipService object.
this.timeoutTimer = new GossipTimeoutTimer(cleanupTimeout, notificationListener, this); * @param cleanupTimeout
} * The cleanup timeout for this gossip member.
*/
public LocalGossipMember(String hostname, int port, String id, int heartbeat,
NotificationListener notificationListener, int cleanupTimeout) {
super(hostname, port, id, heartbeat);
/** this.timeoutTimer = new GossipTimeoutTimer(cleanupTimeout, notificationListener, this);
* Start the timeout timer. }
*/
public void startTimeoutTimer() {
this.timeoutTimer.start();
}
/** /**
* Reset the timeout timer. * Start the timeout timer.
*/ */
public void resetTimeoutTimer() { public void startTimeoutTimer() {
this.timeoutTimer.reset(); this.timeoutTimer.start();
} }
/**
* Reset the timeout timer.
*/
public void resetTimeoutTimer() {
this.timeoutTimer.reset();
}
} }

42
src/main/java/com/google/code/gossip/LogLevel.java
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@ -2,24 +2,26 @@ package com.google.code.gossip;
public class LogLevel { public class LogLevel {
public static final String CONFIG_ERROR = "ERROR"; public static final String CONFIG_ERROR = "ERROR";
public static final String CONFIG_INFO = "INFO"; public static final String CONFIG_INFO = "INFO";
public static final String CONFIG_DEBUG = "DEBUG"; public static final String CONFIG_DEBUG = "DEBUG";
public static final int ERROR = 1; public static final int ERROR = 1;
public static final int INFO = 2;
public static final int DEBUG = 3; public static final int INFO = 2;
public static int fromString(String logLevel) { public static final int DEBUG = 3;
if (logLevel.equals(CONFIG_ERROR))
return ERROR; public static int fromString(String logLevel) {
else if (logLevel.equals(CONFIG_INFO)) if (logLevel.equals(CONFIG_ERROR))
return INFO; return ERROR;
else if (logLevel.equals(CONFIG_DEBUG)) else if (logLevel.equals(CONFIG_INFO))
return DEBUG; return INFO;
else else if (logLevel.equals(CONFIG_DEBUG))
return INFO; return DEBUG;
} else
return INFO;
}
} }

46
src/main/java/com/google/code/gossip/RemoteGossipMember.java
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@ -1,28 +1,36 @@
package com.google.code.gossip; package com.google.code.gossip;
/** /**
* The object represents a gossip member with the properties as received from a remote gossip member. * The object represents a gossip member with the properties as received from a remote gossip
* member.
* *
* @author harmenw * @author harmenw
*/ */
public class RemoteGossipMember extends GossipMember { public class RemoteGossipMember extends GossipMember {
/** /**
* Constructor. * Constructor.
* @param host The hostname or IP address. *
* @param port The port number. * @param host
* @param heartbeat The current heartbeat. * The hostname or IP address.
*/ * @param port
public RemoteGossipMember(String hostname, int port, String id, int heartbeat) { * The port number.
super(hostname, port, id, heartbeat); * @param heartbeat
} * The current heartbeat.
*/
/** public RemoteGossipMember(String hostname, int port, String id, int heartbeat) {
* Construct a RemoteGossipMember with a heartbeat of 0. super(hostname, port, id, heartbeat);
* @param host The hostname or IP address. }
* @param port The port number.
*/ /**
public RemoteGossipMember(String hostname, int port, String id) { * Construct a RemoteGossipMember with a heartbeat of 0.
super(hostname, port, id, 0); *
} * @param host
* The hostname or IP address.
* @param port
* The port number.
*/
public RemoteGossipMember(String hostname, int port, String id) {
super(hostname, port, id, 0);
}
} }

303
src/main/java/com/google/code/gossip/StartupSettings.java
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@ -17,145 +17,168 @@ import org.json.JSONObject;
* @author harmenw * @author harmenw
*/ */
public class StartupSettings { public class StartupSettings {
/** The port to start the gossip service on. */
private int _port;
/** The logging level of the gossip service. */
private int _logLevel;
/** The gossip settings used at startup. */
private GossipSettings _gossipSettings;
/** The list with gossip members to start with. */
private ArrayList<GossipMember> _gossipMembers;
/**
* Constructor.
* @param port The port to start the service on.
*/
public StartupSettings(int port, int logLevel) {
this(port, logLevel, new GossipSettings());
}
/**
* Constructor.
* @param port The port to start the service on.
*/
public StartupSettings(int port, int logLevel, GossipSettings gossipSettings) {
_port = port;
_logLevel = logLevel;
_gossipSettings = gossipSettings;
_gossipMembers = new ArrayList<GossipMember>();
}
/**
* Set the port of the gossip service.
* @param port The port for the gossip service.
*/
public void setPort(int port) {
_port = port;
}
/**
* Get the port for the gossip service.
* @return The port of the gossip service.
*/
public int getPort() {
return _port;
}
/**
* Set the log level of the gossip service.
* @param logLevel The log level({LogLevel}).
*/
public void setLogLevel(int logLevel) {
_logLevel = logLevel;
}
/**
* Get the log level of the gossip service.
* @return The log level.
*/
public int getLogLevel() {
return _logLevel;
}
/**
* Get the GossipSettings.
* @return The GossipSettings object.
*/
public GossipSettings getGossipSettings() {
return _gossipSettings;
}
/**
* Add a gossip member to the list of members to start with.
* @param member The member to add.
*/
public void addGossipMember(GossipMember member) {
_gossipMembers.add(member);
}
/**
* Get the list with gossip members.
* @return The gossip members.
*/
public ArrayList<GossipMember> getGossipMembers() {
return _gossipMembers;
}
/**
* Parse the settings for the gossip service from a JSON file.
* @param jsonFile The file object which refers to the JSON config file.
* @return The StartupSettings object with the settings from the config file.
* @throws JSONException Thrown when the file is not well-formed JSON.
* @throws FileNotFoundException Thrown when the file cannot be found.
* @throws IOException Thrown when reading the file gives problems.
*/
public static StartupSettings fromJSONFile(File jsonFile) throws JSONException, FileNotFoundException, IOException {
// Read the file to a String.
BufferedReader br = new BufferedReader(new FileReader(jsonFile));
StringBuffer buffer = new StringBuffer();
String line;
while((line = br.readLine()) != null) {
buffer.append(line.trim());
}
// Lets parse the String as JSON.
JSONObject jsonObject = new JSONArray(buffer.toString()).getJSONObject(0);
// Now get the port number.
int port = jsonObject.getInt("port");
// Get the log level from the config file. /** The port to start the gossip service on. */
int logLevel = LogLevel.fromString(jsonObject.getString("log_level")); private int _port;
// Get the gossip_interval from the config file. /** The logging level of the gossip service. */
int gossipInterval = jsonObject.getInt("gossip_interval"); private int _logLevel;
// Get the cleanup_interval from the config file. /** The gossip settings used at startup. */
int cleanupInterval = jsonObject.getInt("cleanup_interval"); private GossipSettings _gossipSettings;
System.out.println("Config [port: " + port + ", log_level: " + logLevel + ", gossip_interval: " + gossipInterval + ", cleanup_interval: " + cleanupInterval + "]"); /** The list with gossip members to start with. */
private ArrayList<GossipMember> _gossipMembers;
// Initiate the settings with the port number.
StartupSettings settings = new StartupSettings(port, logLevel, new GossipSettings(gossipInterval, cleanupInterval)); /**
* Constructor.
// Now iterate over the members from the config file and add them to the settings. *
System.out.print("Config-members ["); * @param port
JSONArray membersJSON = jsonObject.getJSONArray("members"); * The port to start the service on.
for (int i=0; i<membersJSON.length(); i++) { */
JSONObject memberJSON = membersJSON.getJSONObject(i); public StartupSettings(int port, int logLevel) {
RemoteGossipMember member = new RemoteGossipMember(memberJSON.getString("host"), memberJSON.getInt("port"), ""); this(port, logLevel, new GossipSettings());
settings.addGossipMember(member); }
System.out.print(member.getAddress());
if (i < (membersJSON.length() - 1)) /**
System.out.print(", "); * Constructor.
} *
System.out.println("]"); * @param port
* The port to start the service on.
// Return the created settings object. */
return settings; public StartupSettings(int port, int logLevel, GossipSettings gossipSettings) {
} _port = port;
_logLevel = logLevel;
_gossipSettings = gossipSettings;
_gossipMembers = new ArrayList<GossipMember>();
}
/**
* Set the port of the gossip service.
*
* @param port
* The port for the gossip service.
*/
public void setPort(int port) {
_port = port;
}
/**
* Get the port for the gossip service.
*
* @return The port of the gossip service.
*/
public int getPort() {
return _port;
}
/**
* Set the log level of the gossip service.
*
* @param logLevel
* The log level({LogLevel}).
*/
public void setLogLevel(int logLevel) {
_logLevel = logLevel;
}
/**
* Get the log level of the gossip service.
*
* @return The log level.
*/
public int getLogLevel() {
return _logLevel;
}
/**
* Get the GossipSettings.
*
* @return The GossipSettings object.
*/
public GossipSettings getGossipSettings() {
return _gossipSettings;
}
/**
* Add a gossip member to the list of members to start with.
*
* @param member
* The member to add.
*/
public void addGossipMember(GossipMember member) {
_gossipMembers.add(member);
}
/**
* Get the list with gossip members.
*
* @return The gossip members.
*/
public ArrayList<GossipMember> getGossipMembers() {
return _gossipMembers;
}
/**
* Parse the settings for the gossip service from a JSON file.
*
* @param jsonFile
* The file object which refers to the JSON config file.
* @return The StartupSettings object with the settings from the config file.
* @throws JSONException
* Thrown when the file is not well-formed JSON.
* @throws FileNotFoundException
* Thrown when the file cannot be found.
* @throws IOException
* Thrown when reading the file gives problems.
*/
public static StartupSettings fromJSONFile(File jsonFile) throws JSONException,
FileNotFoundException, IOException {
// Read the file to a String.
BufferedReader br = new BufferedReader(new FileReader(jsonFile));
StringBuffer buffer = new StringBuffer();
String line;
while ((line = br.readLine()) != null) {
buffer.append(line.trim());
}
// Lets parse the String as JSON.
JSONObject jsonObject = new JSONArray(buffer.toString()).getJSONObject(0);
// Now get the port number.
int port = jsonObject.getInt("port");
// Get the log level from the config file.
int logLevel = LogLevel.fromString(jsonObject.getString("log_level"));
// Get the gossip_interval from the config file.
int gossipInterval = jsonObject.getInt("gossip_interval");
// Get the cleanup_interval from the config file.
int cleanupInterval = jsonObject.getInt("cleanup_interval");
System.out.println("Config [port: " + port + ", log_level: " + logLevel + ", gossip_interval: "
+ gossipInterval + ", cleanup_interval: " + cleanupInterval + "]");
// Initiate the settings with the port number.
StartupSettings settings = new StartupSettings(port, logLevel, new GossipSettings(
gossipInterval, cleanupInterval));
// Now iterate over the members from the config file and add them to the settings.
System.out.print("Config-members [");
JSONArray membersJSON = jsonObject.getJSONArray("members");
for (int i = 0; i < membersJSON.length(); i++) {
JSONObject memberJSON = membersJSON.getJSONObject(i);
RemoteGossipMember member = new RemoteGossipMember(memberJSON.getString("host"),
memberJSON.getInt("port"), "");
settings.addGossipMember(member);
System.out.print(member.getAddress());
if (i < (membersJSON.length() - 1))
System.out.print(", ");
}
System.out.println("]");
// Return the created settings object.
return settings;
}
} }

118
src/main/java/com/google/code/gossip/examples/GossipExample.java
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@ -1,6 +1,5 @@
package com.google.code.gossip.examples; package com.google.code.gossip.examples;
import java.net.InetAddress; import java.net.InetAddress;
import java.net.UnknownHostException; import java.net.UnknownHostException;
import java.util.ArrayList; import java.util.ArrayList;
@ -12,67 +11,70 @@ import com.google.code.gossip.LogLevel;
import com.google.code.gossip.RemoteGossipMember; import com.google.code.gossip.RemoteGossipMember;
/** /**
* This class is an example of how one could use the gossip service. * This class is an example of how one could use the gossip service. Here we start multiple gossip
* Here we start multiple gossip clients on this host as specified in the config file. * clients on this host as specified in the config file.
* *
* @author harmenw * @author harmenw
*/ */
public class GossipExample extends Thread { public class GossipExample extends Thread {
/** The number of clients to start. */ /** The number of clients to start. */
private static final int NUMBER_OF_CLIENTS = 4; private static final int NUMBER_OF_CLIENTS = 4;
/** /**
* @param args * @param args
*/ */
public static void main(String[] args) { public static void main(String[] args) {
new GossipExample(); new GossipExample();
} }
/**
* Constructor.
* This will start the this thread.
*/
public GossipExample() {
start();
}
/** /**
* @see java.lang.Thread#run() * Constructor. This will start the this thread.
*/ */
public void run() { public GossipExample() {
try { start();
GossipSettings settings = new GossipSettings(); }
ArrayList<GossipService> clients = new ArrayList<GossipService>(); /**
* @see java.lang.Thread#run()
// Get my ip address. */
String myIpAddress = InetAddress.getLocalHost().getHostAddress(); public void run() {
try {
// Create the gossip members and put them in a list and give them a port number starting with 2000. GossipSettings settings = new GossipSettings();
ArrayList<GossipMember> startupMembers = new ArrayList<GossipMember>();
for (int i=0; i<NUMBER_OF_CLIENTS; ++i) { ArrayList<GossipService> clients = new ArrayList<GossipService>();
startupMembers.add(new RemoteGossipMember(myIpAddress, 2000+i, ""));
} // Get my ip address.
String myIpAddress = InetAddress.getLocalHost().getHostAddress();
// Lets start the gossip clients.
// Start the clients, waiting cleaning-interval + 1 second between them which will show the dead list handling. // Create the gossip members and put them in a list and give them a port number starting with
for (GossipMember member : startupMembers) { // 2000.
GossipService gossipService = new GossipService(myIpAddress, member.getPort(), "", LogLevel.DEBUG, startupMembers, settings); ArrayList<GossipMember> startupMembers = new ArrayList<GossipMember>();
clients.add(gossipService); for (int i = 0; i < NUMBER_OF_CLIENTS; ++i) {
gossipService.start(); startupMembers.add(new RemoteGossipMember(myIpAddress, 2000 + i, ""));
sleep(settings.getCleanupInterval() + 1000); }
}
// Lets start the gossip clients.
// After starting all gossip clients, first wait 10 seconds and then shut them down. // Start the clients, waiting cleaning-interval + 1 second between them which will show the
sleep(10000); // dead list handling.
System.err.println("Going to shutdown all services..."); for (GossipMember member : startupMembers) {
// Since they all run in the same virtual machine and share the same executor, if one is shutdown they will all stop. GossipService gossipService = new GossipService(myIpAddress, member.getPort(), "",
clients.get(0).shutdown(); LogLevel.DEBUG, startupMembers, settings);
clients.add(gossipService);
} catch (UnknownHostException e) { gossipService.start();
e.printStackTrace(); sleep(settings.getCleanupInterval() + 1000);
} catch (InterruptedException e) { }
e.printStackTrace();
} // After starting all gossip clients, first wait 10 seconds and then shut them down.
} sleep(10000);
System.err.println("Going to shutdown all services...");
// Since they all run in the same virtual machine and share the same executor, if one is
// shutdown they will all stop.
clients.get(0).shutdown();
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
} }

85
src/main/java/com/google/code/gossip/manager/ActiveGossipThread.java
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@ -8,51 +8,52 @@ import com.google.code.gossip.GossipService;
import com.google.code.gossip.LocalGossipMember; import com.google.code.gossip.LocalGossipMember;
/** /**
* [The active thread: periodically send gossip request.] * [The active thread: periodically send gossip request.] The class handles gossiping the membership
* The class handles gossiping the membership list. * list. This information is important to maintaining a common state among all the nodes, and is
* This information is important to maintaining a common * important for detecting failures.
* state among all the nodes, and is important for detecting
* failures.
*/ */
abstract public class ActiveGossipThread implements Runnable { abstract public class ActiveGossipThread implements Runnable {
private GossipManager _gossipManager;
private final AtomicBoolean _keepRunning;
public ActiveGossipThread(GossipManager gossipManager) { private GossipManager _gossipManager;
_gossipManager = gossipManager;
_keepRunning = new AtomicBoolean(true);
}
@Override private final AtomicBoolean _keepRunning;
public void run() {
while(_keepRunning.get()) {
try {
TimeUnit.MILLISECONDS.sleep(_gossipManager.getSettings().getGossipInterval());
sendMembershipList(_gossipManager.getMyself(), _gossipManager.getMemberList());
} catch (InterruptedException e) {
GossipService.LOGGER.error(e);
_keepRunning.set(false);
}
}
shutdown();
}
public void shutdown(){
_keepRunning.set(false);
}
/**
* Performs the sending of the membership list, after we have
* incremented our own heartbeat.
*/
abstract protected void sendMembershipList(LocalGossipMember me, ArrayList<LocalGossipMember> memberList);
/** public ActiveGossipThread(GossipManager gossipManager) {
* Abstract method which should be implemented by a subclass. _gossipManager = gossipManager;
* This method should return a member of the list to gossip with. _keepRunning = new AtomicBoolean(true);
* @param memberList The list of members which are stored in the local list of members. }
* @return The chosen LocalGossipMember to gossip with.
*/ @Override
abstract protected LocalGossipMember selectPartner(ArrayList<LocalGossipMember> memberList); public void run() {
while (_keepRunning.get()) {
try {
TimeUnit.MILLISECONDS.sleep(_gossipManager.getSettings().getGossipInterval());
sendMembershipList(_gossipManager.getMyself(), _gossipManager.getMemberList());
} catch (InterruptedException e) {
GossipService.LOGGER.error(e);
_keepRunning.set(false);
}
}
shutdown();
}
public void shutdown() {
_keepRunning.set(false);
}
/**
* Performs the sending of the membership list, after we have incremented our own heartbeat.
*/
abstract protected void sendMembershipList(LocalGossipMember me,
ArrayList<LocalGossipMember> memberList);
/**
* Abstract method which should be implemented by a subclass. This method should return a member
* of the list to gossip with.
*
* @param memberList
* The list of members which are stored in the local list of members.
* @return The chosen LocalGossipMember to gossip with.
*/
abstract protected LocalGossipMember selectPartner(ArrayList<LocalGossipMember> memberList);
} }

233
src/main/java/com/google/code/gossip/manager/GossipManager.java
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@ -16,142 +16,147 @@ import com.google.code.gossip.GossipSettings;
import com.google.code.gossip.LocalGossipMember; import com.google.code.gossip.LocalGossipMember;
public abstract class GossipManager extends Thread implements NotificationListener { public abstract class GossipManager extends Thread implements NotificationListener {
/** The maximal number of bytes the packet with the GOSSIP may be. (Default is 100 kb) */ /** The maximal number of bytes the packet with the GOSSIP may be. (Default is 100 kb) */
public static final int MAX_PACKET_SIZE = 102400; public static final int MAX_PACKET_SIZE = 102400;
/** The list of members which are in the gossip group (not including myself). */
private ArrayList<LocalGossipMember> _memberList;
/** The list of members which are known to be dead. */ /** The list of members which are in the gossip group (not including myself). */
private ArrayList<LocalGossipMember> _deadList; private ArrayList<LocalGossipMember> _memberList;
/** The member I am representing. */ /** The list of members which are known to be dead. */
private LocalGossipMember _me; private ArrayList<LocalGossipMember> _deadList;
/** The settings for gossiping. */ /** The member I am representing. */
private GossipSettings _settings; private LocalGossipMember _me;
/** A boolean whether the gossip service should keep running. */ /** The settings for gossiping. */
private AtomicBoolean _gossipServiceRunning; private GossipSettings _settings;
/** A boolean whether the gossip service should keep running. */
private AtomicBoolean _gossipServiceRunning;
/** A ExecutorService used for executing the active and passive gossip threads. */
private ExecutorService _gossipThreadExecutor;
private Class<? extends PassiveGossipThread> _passiveGossipThreadClass;
private PassiveGossipThread passiveGossipThread;
private Class<? extends ActiveGossipThread> _activeGossipThreadClass;
private ActiveGossipThread activeGossipThread;
/** A ExecutorService used for executing the active and passive gossip threads. */
private ExecutorService _gossipThreadExecutor;
private Class<? extends PassiveGossipThread> _passiveGossipThreadClass;
private PassiveGossipThread passiveGossipThread;
private Class<? extends ActiveGossipThread> _activeGossipThreadClass;
private ActiveGossipThread activeGossipThread;
public GossipManager(Class<? extends PassiveGossipThread> passiveGossipThreadClass, public GossipManager(Class<? extends PassiveGossipThread> passiveGossipThreadClass,
Class<? extends ActiveGossipThread> activeGossipThreadClass, String address, int port, Class<? extends ActiveGossipThread> activeGossipThreadClass, String address, int port,
String id, GossipSettings settings, ArrayList<GossipMember> gossipMembers) { String id, GossipSettings settings, ArrayList<GossipMember> gossipMembers) {
_passiveGossipThreadClass = passiveGossipThreadClass; _passiveGossipThreadClass = passiveGossipThreadClass;
_activeGossipThreadClass = activeGossipThreadClass; _activeGossipThreadClass = activeGossipThreadClass;
_settings = settings; _settings = settings;
_me = new LocalGossipMember(address, port, id, 0, this, settings.getCleanupInterval()); _me = new LocalGossipMember(address, port, id, 0, this, settings.getCleanupInterval());
_memberList = new ArrayList<LocalGossipMember>(); _memberList = new ArrayList<LocalGossipMember>();
_deadList = new ArrayList<LocalGossipMember>(); _deadList = new ArrayList<LocalGossipMember>();
for (GossipMember startupMember : gossipMembers) { for (GossipMember startupMember : gossipMembers) {
if (!startupMember.equals(_me)) { if (!startupMember.equals(_me)) {
LocalGossipMember member = new LocalGossipMember(startupMember.getHost(), LocalGossipMember member = new LocalGossipMember(startupMember.getHost(),
startupMember.getPort(), startupMember.getId(), 0, this, startupMember.getPort(), startupMember.getId(), 0, this,
settings.getCleanupInterval()); settings.getCleanupInterval());
_memberList.add(member); _memberList.add(member);
GossipService.LOGGER.debug(member); GossipService.LOGGER.debug(member);
} }
} }
_gossipServiceRunning = new AtomicBoolean(true);
Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {
public void run() {
GossipService.LOGGER.info("Service has been shutdown...");
}
}));
}
/**
* All timers associated with a member will trigger this method when it goes
* off. The timer will go off if we have not heard from this member in
* <code> _settings.T_CLEANUP </code> time.
*/
@Override
public void handleNotification(Notification notification, Object handback) {
LocalGossipMember deadMember = (LocalGossipMember) notification.getUserData();
GossipService.LOGGER.info("Dead member detected: " + deadMember);
synchronized (this._memberList) {
this._memberList.remove(deadMember);
}
synchronized (this._deadList) {
this._deadList.add(deadMember);
}
}
public GossipSettings getSettings() { _gossipServiceRunning = new AtomicBoolean(true);
return _settings; Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {
} public void run() {
GossipService.LOGGER.info("Service has been shutdown...");
}
}));
}
/** /**
* Get a clone of the memberlist. * All timers associated with a member will trigger this method when it goes off. The timer will
* @return * go off if we have not heard from this member in <code> _settings.T_CLEANUP </code> time.
*/ */
public ArrayList<LocalGossipMember> getMemberList() { @Override
return _memberList; public void handleNotification(Notification notification, Object handback) {
} LocalGossipMember deadMember = (LocalGossipMember) notification.getUserData();
GossipService.LOGGER.info("Dead member detected: " + deadMember);
public LocalGossipMember getMyself() { synchronized (this._memberList) {
return _me; this._memberList.remove(deadMember);
} }
synchronized (this._deadList) {
this._deadList.add(deadMember);
}
}
public ArrayList<LocalGossipMember> getDeadList() { public GossipSettings getSettings() {
return _deadList; return _settings;
} }
/** /**
* Starts the client. Specifically, start the various cycles for this protocol. * Get a clone of the memberlist.
* Start the gossip thread and start the receiver thread. *
* @throws InterruptedException * @return
*/ */
public void run() { public ArrayList<LocalGossipMember> getMemberList() {
for (LocalGossipMember member : _memberList) { return _memberList;
if (member != _me) { }
member.startTimeoutTimer();
} public LocalGossipMember getMyself() {
} return _me;
}
public ArrayList<LocalGossipMember> getDeadList() {
return _deadList;
}
/**
* Starts the client. Specifically, start the various cycles for this protocol. Start the gossip
* thread and start the receiver thread.
*
* @throws InterruptedException
*/
public void run() {
for (LocalGossipMember member : _memberList) {
if (member != _me) {
member.startTimeoutTimer();
}
}
_gossipThreadExecutor = Executors.newCachedThreadPool(); _gossipThreadExecutor = Executors.newCachedThreadPool();
try { try {
passiveGossipThread = _passiveGossipThreadClass.getConstructor(GossipManager.class).newInstance(this); passiveGossipThread = _passiveGossipThreadClass.getConstructor(GossipManager.class)
.newInstance(this);
_gossipThreadExecutor.execute(passiveGossipThread); _gossipThreadExecutor.execute(passiveGossipThread);
activeGossipThread = _activeGossipThreadClass.getConstructor(GossipManager.class).newInstance(this); activeGossipThread = _activeGossipThreadClass.getConstructor(GossipManager.class)
.newInstance(this);
_gossipThreadExecutor.execute(activeGossipThread); _gossipThreadExecutor.execute(activeGossipThread);
} catch (InstantiationException | IllegalAccessException | IllegalArgumentException } catch (InstantiationException | IllegalAccessException | IllegalArgumentException
| InvocationTargetException | NoSuchMethodException | SecurityException e1) { | InvocationTargetException | NoSuchMethodException | SecurityException e1) {
throw new RuntimeException(e1); throw new RuntimeException(e1);
} }
GossipService.LOGGER.info("The GossipService is started."); GossipService.LOGGER.info("The GossipService is started.");
while(_gossipServiceRunning.get()) { while (_gossipServiceRunning.get()) {
try { try {
//TODO // TODO
TimeUnit.MILLISECONDS.sleep(1); TimeUnit.MILLISECONDS.sleep(1);
} catch (InterruptedException e) { } catch (InterruptedException e) {
GossipService.LOGGER.info("The GossipClient was interrupted."); GossipService.LOGGER.info("The GossipClient was interrupted.");
} }
} }
} }
/** /**
* Shutdown the gossip service. * Shutdown the gossip service.
*/ */
public void shutdown() { public void shutdown() {
_gossipThreadExecutor.shutdown(); _gossipThreadExecutor.shutdown();
passiveGossipThread.shutdown(); passiveGossipThread.shutdown();
activeGossipThread.shutdown(); activeGossipThread.shutdown();
try { try {
boolean result = _gossipThreadExecutor.awaitTermination(1000, TimeUnit.MILLISECONDS); boolean result = _gossipThreadExecutor.awaitTermination(1000, TimeUnit.MILLISECONDS);
System.err.println("Terminate retuned " + result); System.err.println("Terminate retuned " + result);
} catch (InterruptedException e) { } catch (InterruptedException e) {
e.printStackTrace(); e.printStackTrace();
} }
_gossipServiceRunning.set(false); _gossipServiceRunning.set(false);
} }
} }

78
src/main/java/com/google/code/gossip/manager/PassiveGossipThread.java
View File

@ -18,36 +18,36 @@ import com.google.code.gossip.GossipService;
import com.google.code.gossip.RemoteGossipMember; import com.google.code.gossip.RemoteGossipMember;
/** /**
* [The passive thread: reply to incoming gossip request.] * [The passive thread: reply to incoming gossip request.] This class handles the passive cycle,
* This class handles the passive cycle, where this client * where this client has received an incoming message. For now, this message is always the
* has received an incoming message. For now, this message * membership list, but if you choose to gossip additional information, you will need some logic to
* is always the membership list, but if you choose to gossip * determine the incoming message.
* additional information, you will need some logic to determine
* the incoming message.
*/ */
abstract public class PassiveGossipThread implements Runnable { abstract public class PassiveGossipThread implements Runnable {
/** The socket used for the passive thread of the gossip service. */
private DatagramSocket _server;
private GossipManager _gossipManager;
private AtomicBoolean _keepRunning; /** The socket used for the passive thread of the gossip service. */
private DatagramSocket _server;
public PassiveGossipThread(GossipManager gossipManager) { private GossipManager _gossipManager;
_gossipManager = gossipManager;
try { private AtomicBoolean _keepRunning;
SocketAddress socketAddress = new InetSocketAddress(_gossipManager.getMyself().getHost(), _gossipManager.getMyself().getPort());
_server = new DatagramSocket(socketAddress); public PassiveGossipThread(GossipManager gossipManager) {
GossipService.LOGGER.info("Gossip service successfully initialized on port " + _gossipManager.getMyself().getPort()); _gossipManager = gossipManager;
GossipService.LOGGER.debug("I am " + _gossipManager.getMyself()); try {
} catch (SocketException ex) { SocketAddress socketAddress = new InetSocketAddress(_gossipManager.getMyself().getHost(),
GossipService.LOGGER.error(ex); _gossipManager.getMyself().getPort());
_server = null; _server = new DatagramSocket(socketAddress);
throw new RuntimeException(ex); GossipService.LOGGER.info("Gossip service successfully initialized on port "
} + _gossipManager.getMyself().getPort());
_keepRunning = new AtomicBoolean(true); GossipService.LOGGER.debug("I am " + _gossipManager.getMyself());
} } catch (SocketException ex) {
GossipService.LOGGER.error(ex);
_server = null;
throw new RuntimeException(ex);
}
_keepRunning = new AtomicBoolean(true);
}
@Override @Override
public void run() { public void run() {
@ -127,16 +127,22 @@ abstract public class PassiveGossipThread implements Runnable {
} }
shutdown(); shutdown();
} }
public void shutdown(){ public void shutdown() {
_server.close(); _server.close();
} }
/** /**
* Abstract method for merging the local and remote list. * Abstract method for merging the local and remote list.
* @param gossipManager The GossipManager for retrieving the local members and dead members list. *
* @param senderMember The member who is sending this list, this could be used to send a response if the remote list contains out-dated information. * @param gossipManager
* @param remoteList The list of members known at the remote side. * The GossipManager for retrieving the local members and dead members list.
*/ * @param senderMember
abstract protected void mergeLists(GossipManager gossipManager, RemoteGossipMember senderMember, ArrayList<GossipMember> remoteList); * The member who is sending this list, this could be used to send a response if the
* remote list contains out-dated information.
* @param remoteList
* The list of members known at the remote side.
*/
abstract protected void mergeLists(GossipManager gossipManager, RemoteGossipMember senderMember,
ArrayList<GossipMember> remoteList);
} }

164
src/main/java/com/google/code/gossip/manager/impl/OnlyProcessReceivedPassiveGossipThread.java
View File

@ -11,83 +11,101 @@ import com.google.code.gossip.manager.PassiveGossipThread;
public class OnlyProcessReceivedPassiveGossipThread extends PassiveGossipThread { public class OnlyProcessReceivedPassiveGossipThread extends PassiveGossipThread {
public OnlyProcessReceivedPassiveGossipThread(GossipManager gossipManager) { public OnlyProcessReceivedPassiveGossipThread(GossipManager gossipManager) {
super(gossipManager); super(gossipManager);
} }
/** /**
* Merge remote list (received from peer), and our local member list. * Merge remote list (received from peer), and our local member list. Simply, we must update the
* Simply, we must update the heartbeats that the remote list has with * heartbeats that the remote list has with our list. Also, some additional logic is needed to
* our list. Also, some additional logic is needed to make sure we have * make sure we have not timed out a member and then immediately received a list with that member.
* not timed out a member and then immediately received a list with that *
* member. * @param remoteList
* @param remoteList */
*/ protected void mergeLists(GossipManager gossipManager, RemoteGossipMember senderMember,
protected void mergeLists(GossipManager gossipManager, RemoteGossipMember senderMember, ArrayList<GossipMember> remoteList) { ArrayList<GossipMember> remoteList) {
synchronized (gossipManager.getDeadList()) { synchronized (gossipManager.getDeadList()) {
synchronized (gossipManager.getMemberList()) { synchronized (gossipManager.getMemberList()) {
for (GossipMember remoteMember : remoteList) { for (GossipMember remoteMember : remoteList) {
// Skip myself. We don't want ourselves in the local member list. // Skip myself. We don't want ourselves in the local member list.
if (!remoteMember.equals(gossipManager.getMyself())) { if (!remoteMember.equals(gossipManager.getMyself())) {
if (gossipManager.getMemberList().contains(remoteMember)) { if (gossipManager.getMemberList().contains(remoteMember)) {
GossipService.LOGGER.debug("The local list already contains the remote member (" + remoteMember + ")."); GossipService.LOGGER.debug("The local list already contains the remote member ("
// The local memberlist contains the remote member. + remoteMember + ").");
LocalGossipMember localMember = gossipManager.getMemberList().get(gossipManager.getMemberList().indexOf(remoteMember)); // The local memberlist contains the remote member.
LocalGossipMember localMember = gossipManager.getMemberList().get(
gossipManager.getMemberList().indexOf(remoteMember));
// Let's synchronize it's heartbeat. // Let's synchronize it's heartbeat.
if (remoteMember.getHeartbeat() > localMember.getHeartbeat()) { if (remoteMember.getHeartbeat() > localMember.getHeartbeat()) {
// update local list with latest heartbeat // update local list with latest heartbeat
localMember.setHeartbeat(remoteMember.getHeartbeat()); localMember.setHeartbeat(remoteMember.getHeartbeat());
// and reset the timeout of that member // and reset the timeout of that member
localMember.resetTimeoutTimer(); localMember.resetTimeoutTimer();
} }
// TODO: Otherwise, should we inform the other when the heartbeat is already higher? // TODO: Otherwise, should we inform the other when the heartbeat is already higher?
} else { } else {
// The local list does not contain the remote member. // The local list does not contain the remote member.
GossipService.LOGGER.debug("The local list does not contain the remote member (" + remoteMember + ")."); GossipService.LOGGER.debug("The local list does not contain the remote member ("
+ remoteMember + ").");
// The remote member is either brand new, or a previously declared dead member.
// If its dead, check the heartbeat because it may have come back from the dead.
if (gossipManager.getDeadList().contains(remoteMember)) {
// The remote member is known here as a dead member.
GossipService.LOGGER.debug("The remote member is known here as a dead member.");
LocalGossipMember localDeadMember = gossipManager.getDeadList().get(
gossipManager.getDeadList().indexOf(remoteMember));
// If a member is restarted the heartbeat will restart from 1, so we should check
// that here.
// So a member can become from the dead when it is either larger than a previous
// heartbeat (due to network failure)
// or when the heartbeat is 1 (after a restart of the service).
// TODO: What if the first message of a gossip service is sent to a dead node? The
// second member will receive a heartbeat of two.
// TODO: The above does happen. Maybe a special message for a revived member?
// TODO: Or maybe when a member is declared dead for more than
// _settings.getCleanupInterval() ms, reset the heartbeat to 0.
// It will then accept a revived member.
// The above is now handle by checking whether the heartbeat differs
// _settings.getCleanupInterval(), it must be restarted.
if (remoteMember.getHeartbeat() == 1
|| ((localDeadMember.getHeartbeat() - remoteMember.getHeartbeat()) * -1) > (gossipManager
.getSettings().getCleanupInterval() / 1000)
|| remoteMember.getHeartbeat() > localDeadMember.getHeartbeat()) {
GossipService.LOGGER
.debug("The remote member is back from the dead. We will remove it from the dead list and add it as a new member.");
// The remote member is back from the dead.
// Remove it from the dead list.
gossipManager.getDeadList().remove(localDeadMember);
// Add it as a new member and add it to the member list.
LocalGossipMember newLocalMember = new LocalGossipMember(remoteMember.getHost(),
remoteMember.getPort(), remoteMember.getId(),
remoteMember.getHeartbeat(), gossipManager, gossipManager.getSettings()
.getCleanupInterval());
gossipManager.getMemberList().add(newLocalMember);
newLocalMember.startTimeoutTimer();
GossipService.LOGGER.info("Removed remote member " + remoteMember.getAddress()
+ " from dead list and added to local member list.");
}
} else {
// Brand spanking new member - welcome.
LocalGossipMember newLocalMember = new LocalGossipMember(remoteMember.getHost(),
remoteMember.getPort(), remoteMember.getId(), remoteMember.getHeartbeat(),
gossipManager, gossipManager.getSettings().getCleanupInterval());
gossipManager.getMemberList().add(newLocalMember);
newLocalMember.startTimeoutTimer();
GossipService.LOGGER.info("Added new remote member " + remoteMember.getAddress()
+ " to local member list.");
}
}
}
}
}
}
}
// The remote member is either brand new, or a previously declared dead member.
// If its dead, check the heartbeat because it may have come back from the dead.
if (gossipManager.getDeadList().contains(remoteMember)) {
// The remote member is known here as a dead member.
GossipService.LOGGER.debug("The remote member is known here as a dead member.");
LocalGossipMember localDeadMember = gossipManager.getDeadList().get(gossipManager.getDeadList().indexOf(remoteMember));
// If a member is restarted the heartbeat will restart from 1, so we should check that here.
// So a member can become from the dead when it is either larger than a previous heartbeat (due to network failure)
// or when the heartbeat is 1 (after a restart of the service).
// TODO: What if the first message of a gossip service is sent to a dead node? The second member will receive a heartbeat of two.
// TODO: The above does happen. Maybe a special message for a revived member?
// TODO: Or maybe when a member is declared dead for more than _settings.getCleanupInterval() ms, reset the heartbeat to 0.
// It will then accept a revived member.
// The above is now handle by checking whether the heartbeat differs _settings.getCleanupInterval(), it must be restarted.
if (remoteMember.getHeartbeat() == 1
|| ((localDeadMember.getHeartbeat() - remoteMember.getHeartbeat()) * -1) > (gossipManager.getSettings().getCleanupInterval() / 1000)
|| remoteMember.getHeartbeat() > localDeadMember.getHeartbeat()) {
GossipService.LOGGER.debug("The remote member is back from the dead. We will remove it from the dead list and add it as a new member.");
// The remote member is back from the dead.
// Remove it from the dead list.
gossipManager.getDeadList().remove(localDeadMember);
// Add it as a new member and add it to the member list.
LocalGossipMember newLocalMember = new LocalGossipMember(remoteMember.getHost(), remoteMember.getPort(), remoteMember.getId(), remoteMember.getHeartbeat(), gossipManager, gossipManager.getSettings().getCleanupInterval());
gossipManager.getMemberList().add(newLocalMember);
newLocalMember.startTimeoutTimer();
GossipService.LOGGER.info("Removed remote member " + remoteMember.getAddress() + " from dead list and added to local member list.");
}
} else {
// Brand spanking new member - welcome.
LocalGossipMember newLocalMember = new LocalGossipMember(remoteMember.getHost(), remoteMember.getPort(), remoteMember.getId(), remoteMember.getHeartbeat(), gossipManager, gossipManager.getSettings().getCleanupInterval());
gossipManager.getMemberList().add(newLocalMember);
newLocalMember.startTimeoutTimer();
GossipService.LOGGER.info("Added new remote member " + remoteMember.getAddress() + " to local member list.");
}
}
}
}
}
}
}
} }

143
src/main/java/com/google/code/gossip/manager/impl/SendMembersActiveGossipThread.java
View File

@ -16,79 +16,80 @@ import com.google.code.gossip.manager.GossipManager;
abstract public class SendMembersActiveGossipThread extends ActiveGossipThread { abstract public class SendMembersActiveGossipThread extends ActiveGossipThread {
public SendMembersActiveGossipThread(GossipManager gossipManager) { public SendMembersActiveGossipThread(GossipManager gossipManager) {
super(gossipManager); super(gossipManager);
} }
/**
* Performs the sending of the membership list, after we have
* incremented our own heartbeat.
*/
protected void sendMembershipList(LocalGossipMember me, ArrayList<LocalGossipMember> memberList) {
GossipService.LOGGER.debug("Send sendMembershipList() is called.");
// Increase the heartbeat of myself by 1. /**
me.setHeartbeat(me.getHeartbeat() + 1); * Performs the sending of the membership list, after we have incremented our own heartbeat.
*/
synchronized (memberList) { protected void sendMembershipList(LocalGossipMember me, ArrayList<LocalGossipMember> memberList) {
try { GossipService.LOGGER.debug("Send sendMembershipList() is called.");
LocalGossipMember member = selectPartner(memberList);
// Increase the heartbeat of myself by 1.
me.setHeartbeat(me.getHeartbeat() + 1);
synchronized (memberList) {
try {
LocalGossipMember member = selectPartner(memberList);
if (member != null) {
InetAddress dest = InetAddress.getByName(member.getHost());
// Create a StringBuffer for the JSON message.
JSONArray jsonArray = new JSONArray();
GossipService.LOGGER.debug("Sending memberlist to " + dest + ":" + member.getPort());
GossipService.LOGGER.debug("---------------------");
// First write myself, append the JSON representation of the member to the buffer.
jsonArray.put(me.toJSONObject());
GossipService.LOGGER.debug(me);
// Then write the others.
for (int i = 0; i < memberList.size(); i++) {
LocalGossipMember other = memberList.get(i);
// Append the JSON representation of the member to the buffer.
jsonArray.put(other.toJSONObject());
GossipService.LOGGER.debug(other);
}
GossipService.LOGGER.debug("---------------------");
// Write the objects to a byte array.
byte[] json_bytes = jsonArray.toString().getBytes();
int packet_length = json_bytes.length;
if (packet_length < GossipManager.MAX_PACKET_SIZE) {
// Convert the packet length to the byte representation of the int.
byte[] length_bytes = new byte[4];
length_bytes[0] = (byte) (packet_length >> 24);
length_bytes[1] = (byte) ((packet_length << 8) >> 24);
length_bytes[2] = (byte) ((packet_length << 16) >> 24);
length_bytes[3] = (byte) ((packet_length << 24) >> 24);
GossipService.LOGGER.debug("Sending message (" + packet_length + " bytes): "
+ jsonArray.toString());
if (member != null) {
InetAddress dest = InetAddress.getByName(member.getHost());
// Create a StringBuffer for the JSON message.
JSONArray jsonArray = new JSONArray();
GossipService.LOGGER.debug("Sending memberlist to " + dest + ":" + member.getPort());
GossipService.LOGGER.debug("---------------------");
// First write myself, append the JSON representation of the member to the buffer.
jsonArray.put(me.toJSONObject());
GossipService.LOGGER.debug(me);
// Then write the others.
for (int i=0; i<memberList.size(); i++) {
LocalGossipMember other = memberList.get(i);
// Append the JSON representation of the member to the buffer.
jsonArray.put(other.toJSONObject());
GossipService.LOGGER.debug(other);
}
GossipService.LOGGER.debug("---------------------");
// Write the objects to a byte array.
byte[] json_bytes = jsonArray.toString().getBytes();
int packet_length = json_bytes.length;
if (packet_length < GossipManager.MAX_PACKET_SIZE) {
// Convert the packet length to the byte representation of the int.
byte[] length_bytes = new byte[4];
length_bytes[0] =(byte)( packet_length >> 24 );
length_bytes[1] =(byte)( (packet_length << 8) >> 24 );
length_bytes[2] =(byte)( (packet_length << 16) >> 24 );
length_bytes[3] =(byte)( (packet_length << 24) >> 24 );
GossipService.LOGGER.debug("Sending message ("+packet_length+" bytes): " + jsonArray.toString());
ByteBuffer byteBuffer = ByteBuffer.allocate(4 + json_bytes.length); ByteBuffer byteBuffer = ByteBuffer.allocate(4 + json_bytes.length);
byteBuffer.put(length_bytes); byteBuffer.put(length_bytes);
byteBuffer.put(json_bytes); byteBuffer.put(json_bytes);
byte[] buf = byteBuffer.array(); byte[] buf = byteBuffer.array();
DatagramSocket socket = new DatagramSocket();
DatagramPacket datagramPacket = new DatagramPacket(buf, buf.length, dest, member.getPort());
socket.send(datagramPacket);
socket.close();
} else {
GossipService.LOGGER.error("The length of the to be send message is too large (" + packet_length + " > " + GossipManager.MAX_PACKET_SIZE + ").");
}
}
} catch (IOException e1) { DatagramSocket socket = new DatagramSocket();
e1.printStackTrace(); DatagramPacket datagramPacket = new DatagramPacket(buf, buf.length, dest,
} member.getPort());
} socket.send(datagramPacket);
} socket.close();
} else {
GossipService.LOGGER.error("The length of the to be send message is too large ("
+ packet_length + " > " + GossipManager.MAX_PACKET_SIZE + ").");
}
}
} catch (IOException e1) {
e1.printStackTrace();
}
}
}
} }

48
src/main/java/com/google/code/gossip/manager/random/RandomActiveGossipThread.java
View File

@ -9,30 +9,30 @@ import com.google.code.gossip.manager.GossipManager;
import com.google.code.gossip.manager.impl.SendMembersActiveGossipThread; import com.google.code.gossip.manager.impl.SendMembersActiveGossipThread;
public class RandomActiveGossipThread extends SendMembersActiveGossipThread { public class RandomActiveGossipThread extends SendMembersActiveGossipThread {
/** The Random used for choosing a member to gossip with. */
private Random _random;
public RandomActiveGossipThread(GossipManager gossipManager) { /** The Random used for choosing a member to gossip with. */
super(gossipManager); private Random _random;
_random = new Random();
} public RandomActiveGossipThread(GossipManager gossipManager) {
super(gossipManager);
/** _random = new Random();
* [The selectToSend() function.] }
* Find a random peer from the local membership list.
* In the case where this client is the only member in the list, this method will return null. /**
* @return Member random member if list is greater than 1, null otherwise * [The selectToSend() function.] Find a random peer from the local membership list. In the case
*/ * where this client is the only member in the list, this method will return null.
protected LocalGossipMember selectPartner(ArrayList<LocalGossipMember> memberList) { *
LocalGossipMember member = null; * @return Member random member if list is greater than 1, null otherwise
if (memberList.size() > 0) { */
int randomNeighborIndex = _random.nextInt(memberList.size()); protected LocalGossipMember selectPartner(ArrayList<LocalGossipMember> memberList) {
member = memberList.get(randomNeighborIndex); LocalGossipMember member = null;
} else { if (memberList.size() > 0) {
GossipService.LOGGER.debug("I am alone in this world."); int randomNeighborIndex = _random.nextInt(memberList.size());
} member = memberList.get(randomNeighborIndex);
return member; } else {
} GossipService.LOGGER.debug("I am alone in this world.");
}
return member;
}
} }

8
src/main/java/com/google/code/gossip/manager/random/RandomGossipManager.java
View File

@ -8,7 +8,9 @@ import com.google.code.gossip.manager.GossipManager;
import com.google.code.gossip.manager.impl.OnlyProcessReceivedPassiveGossipThread; import com.google.code.gossip.manager.impl.OnlyProcessReceivedPassiveGossipThread;
public class RandomGossipManager extends GossipManager { public class RandomGossipManager extends GossipManager {
public RandomGossipManager(String address, int port, String id, GossipSettings settings, ArrayList<GossipMember> gossipMembers) { public RandomGossipManager(String address, int port, String id, GossipSettings settings,
super(OnlyProcessReceivedPassiveGossipThread.class, RandomActiveGossipThread.class, address, port, id, settings, gossipMembers); ArrayList<GossipMember> gossipMembers) {
} super(OnlyProcessReceivedPassiveGossipThread.class, RandomActiveGossipThread.class, address,
port, id, settings, gossipMembers);
}
} }