GOSSIP-86 Examples in separate module - Added Readme.
diff --git a/README.md b/README.md
index 86f179a..2eae09d 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,10 @@
The original implementation was forked from https://code.google.com/p/java-gossip/. Several bug fixes and changes have already been added.
+A set of easily-run examples, illustrating various features of Gossip, are available in the gossip-examples module. The README.md file, in that module described how to run those examples.
+
+Below, a list of code snippits which show how to incorproate Apache Gossip into your project.
+
Usage
-----
diff --git a/gossip-examples/.gitignore b/gossip-examples/.gitignore
new file mode 100644
index 0000000..342545a
--- /dev/null
+++ b/gossip-examples/.gitignore
@@ -0,0 +1,2 @@
+# Generated by running examples
+*.mycluster.*.json
diff --git a/gossip-examples/README.md b/gossip-examples/README.md
new file mode 100644
index 0000000..aae7b88
--- /dev/null
+++ b/gossip-examples/README.md
@@ -0,0 +1,246 @@
+Running the Examples
+===================================================
+
+Apache Gossip is designed to run as library used by others. That is, it in intended as a feature to be embedded in other code.
+
+These examples illustrate some simple cases of the invocation of Gossip from an "thin" application layer, to illustrate various
+features of the library.
+
+For additional information see:
+* This [YouTube video](https://www.youtube.com/watch?v=bZXZrp7yBkw&t=39s) illustrating and illuminating the first example.
+* This [YouTube video](https://www.youtube.com/watch?v=SqkJs0QDRdk) illustrating and illuminating the second example.
+* A [general description of the Gossip Protocol](https://en.wikipedia.org/wiki/Gossip_protocol)
+
+Initial setup - Preconditions
+-----------------------------
+These instructions assume that you are using a Unix-like command line interface; translate as necessary.
+
+Prior to running these examples you will need to have your environment set up to run java and Maven
+commands:
+* install java 8 - [https://java.com/](https://java.com/), and
+* install Maven - [https://maven.apache.org/install.html](https://maven.apache.org/install.html)
+
+Then, you will need a local copy of the code. The simplest is to download the project to a local folder:
+* browse to [https://github.com/apache/incubator-gossip](https://github.com/apache/incubator-gossip)
+* click on the "Clone of Download" button
+* click on the "Download ZIP" option
+* unzip the file to in a convenient location
+In what follows, we will call the resulting project folder **incubator-gossip**.
+
+As an alternative, you can also [clone](https://help.github.com/articles/cloning-a-repository/)
+the GitHub repository.
+
+Lastly, you will need to use Maven to build and install the necessary dependencies:
+```
+cd incubator-gossip
+mvn install -DskipTests
+```
+
+When all that is finished are you ready to start running the first example...
+
+
+Running org.apache.gossip.examples.StandAloneNode
+-------------------------------------------------
+This first example illustrates the basic, underlying, communication layer the sets up and maintains a gossip network cluster.
+
+In the [YouTube video](https://www.youtube.com/watch?v=bZXZrp7yBkw&t=39s) there is a description of
+the architecture and a demonstration of running of this example. While the video was created with an earlier version of the system,
+these instructions will get you going on that example.
+
+To run this example from the code (in a clone or download of the archive) simply change your working directory
+to the gossip-examples module and run the application in maven.
+
+Specifically, after cloning or downloading the repository:
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNode -Dexec.args="udp://localhost:10000 0 udp://localhost:10000 0"
+```
+
+This sets up a single StandAloneNode that starts out listening to itself. The arguments are:
+1. The URI (host and port) for the node - **udp://localhost:10000**
+2. The id for the node - **0**
+3. The URI for a "seed" node - **udp://localhost:10000**
+4. The id for that seed node - **0**
+
+Note. To stop the the example, simply kill the process (control-C, for example).
+
+In this application, the output uses a "terminal escape sequence" that clears the
+terminal display and resets the cursor to the upper left corner.
+if, for some reason, this is not working in your case, you can add the (optional) flag '-s' to the args in the
+command line, to suppress this "clear screen" behavior. That is:
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNode -Dexec.args="-s udp://localhost:10000 0 udp://localhost:10000 0"
+```
+
+Normally, you would set up nodes in a network on separate hosts, but in this case, illustrating the basic communications in gossip,
+we are just running all the nodes on the same host, localhost. The seed node will generally be one of the other nodes in the
+network: enough information for this node to (eventually) acquire the list of all nodes in its cluster.
+
+You will see that this gossip node prints out two list of know other nodes, live and dead. The live nodes are nodes assumed to be active and
+connected, the dead nodes are nodes that have "gone missing" long enough to be assumed dormant or disconnected. See details in the video.
+
+With only a single node running in this cluster, there are no other nodes detected, so both the live and dead lists are empty.
+
+Then, in a separate terminal window, cd to the same folder and enter the the same run command with the first two arguments
+changed to reflect the fact that this is a different node
+1. host/port for the node - **udp://localhost:10001**
+2. id for the node - **1**
+
+That is:
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNode -Dexec.args="udp://localhost:10001 1 udp://localhost:10000 0"
+```
+
+Now, because the "seed node" is the first node that we started, this second node is listening to the first node,
+and they exchange list of known nodes. And start listening to each other, so that in short order they both have a list of live notes
+with one member, the other live node in the cluster.
+
+Finally, in yet another terminal window, cd to the same folder and enter the the same run command with the first two arguments changed to
+1. host/port for the node - **udp://localhost:10002**
+2. id for the node - **2**
+
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNode -Dexec.args="udp://localhost:10002 2 udp://localhost:10000 0”
+```
+
+Now the lists of live nodes for the cluster converge to reflect each node's connections to the other two nodes.
+
+To see a node moved to the dead list. Kill the process in one of the running terminals: enter control-c in the terminal window.
+Then the live-dead list of the two remaining nodes will converge to show one node live and one node dead.
+Start the missing node again, and it will again appear in the live list.
+Note, that it does not matter which node goes dormant, every live node (eventually) communicates with some other
+live node in the cluster and gets the necessary updated status information.
+
+If you read the code, you will see that it defines a cluster (name = 'mycluster') and a number of other setup details. See the video for
+a more complete description of the setup and for a more details description of the interactions among the nodes.
+
+Also note, that the process of running these nodes produces a set of JSON files recording node state (in the 'base' directory from where the node
+running). This enables a quicker startup as failed nodes recover. In this example, to recover a node that you have killed,
+using control-c, simply re-issue the command to run the node.
+
+
+Running org.apache.gossip.examples.StandAloneNodeCrdtOrSet
+----------------------------------------------------------
+This second example illustrates the using the data layer to share structured information: a shared representation of a set
+of strings, and a shared counter. The objects representing those shared values are special cases of a Conflict-free Replicated
+Data Type (hence, CRDT).
+
+Here is the problem that is solved by these CRDT objects: since each node in a cluster can message any other node in the cluster
+in any order, the messages that reflect the content of data structure can arrive in any order. For example, one node may add an object
+to the set and send that modified set to another node that removes that object and sends that message to a third node. If the first node
+also sends a message to the third node (with the object in the set), the third node could receive conflicting information. But the CRDT
+data structures always contain enough information to resolve the conflict.
+
+As with the first demo there is a You Tube video that illustrates the problem and shows how it is resolved and illustrates the running
+example: [https://www.youtube.com/watch?v=SqkJs0QDRdk](https://www.youtube.com/watch?v=SqkJs0QDRdk) .
+
+Again, we will run three instances of the example, to illustrate the actions of the nodes in the cluster.
+The arguments to the application are identical to those in the
+first example. The difference in this example is that each node will read "commands" the change the local state of its information. Which we
+will illustrate shortly. But first, lets get the three nodes running:
+
+In the first terminal window:
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNodeCrdtOrSet -Dexec.args="udp://localhost:10000 0 udp://localhost:10000 0"
+```
+
+In the second terminal window:
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNodeCrdtOrSet -Dexec.args="udp://localhost:10001 1 udp://localhost:10000 0"
+```
+
+In the third terminal window:
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneNodeCrdtOrSet -Dexec.args="udp://localhost:10002 2 udp://localhost:10000 0"
+```
+
+Now, at any of the terminal windows, you can type a command from the following set of commands to change the data that is stored locally.
+Note, while you are typing, the terminal output continues, forcing you to type blind, but when you hit the return, to end
+the input line, the input will be briefly displayed before scrolling off the screen.
+
+When you type one of these commands, you can then watch the propagation of that data through the cluster. The commands are:
+```
+a string
+r string
+g number
+```
+* **a** is the 'add' command; it adds the string to the shared set - you should see the set displayed with the new value,
+ eventually, at all nodes.
+* **r** is the 'remove' command; it removes the string from the set (if it exists in the set) - you should see the
+ value eventually leave the set at all nodes
+* **g** is the "global increment" command; it assume that it's argument is a number and adds that number to an accumulator.
+ Eventually, the accumulator at all nodes will settle to the same value.
+
+The CRDT representations of these values assure that all nodes will reach the same end state for the resulting value regardless of the order
+of arrival of information from other nodes in the cluster.
+
+As an augmentation to the video, this [wikipedia article](https://en.wikipedia.org/wiki/Conflict-free_replicated_data_type),
+describing various CRDT representations and their usefulness, as well as some information about interesting applications.
+
+
+Running org.apache.gossip.examples.StandAloneDatacenterAndRack
+--------------------------------------------------------------
+
+This final example illustrates more fine grained control over the expected "responsiveness" of nodes in the cluster.
+
+Apache gossip is designed as a library intended to be embedded in applications which to take advantage of the gossip-protocol
+for peer-to-peer communications. The effectiveness of communications among nodes in a gossip cluster can be tuned
+to the expected latency of message transmission and expected responsiveness of other nodes in the network. This example illustrates
+one model of this type of control: a "data center and rack" model of node distribution. In this model, nodes that are in the same
+'data center' (perhaps on a different 'rack') are assumed to have very lower latency and high fidelity of communications.
+While, nodes in different data centers are assumed to require more time to communicate, and be subject to
+a higher rate of communication failure, so communications can be tuned to tolerate more variation in latency and success of
+transmission, but this result in a longer "settle" time.
+
+Accordingly, the application in this example has a couple of extra arguments, a data center id, and a rack id.
+
+To start the first node (in the first terminal window), type the following:
+
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneDatacenterAndRack -Dexec.args="udp://localhost:10000 0 udp://localhost:10000 0 1 2"
+```
+The first four arguments are the same as in the other two examples, and the last two arguments are the new arguments:
+1. The URI (host and port) for the node - **udp://localhost:10000**
+2. The id for the node - **0**
+3. The URI for a "seed" node - **udp://localhost:10000**
+4. The id for that seed node - **0**
+5. The data center id - **1**
+6. The rack id - **2**
+
+Lets then, set up two additional nodes (each in a separate terminal window), one in the same data center on a different rack,
+and the other in a different data center.
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneDatacenterAndRack -Dexec.args="udp://localhost:10001 1 udp://localhost:10000 0 1 3"
+```
+
+```
+cd incubator-gossip/gossip-examples
+mvn exec:java -Dexec.mainClass=org.apache.gossip.examples.StandAloneDatacenterAndRack -Dexec.args="udp://localhost:10002 2 udp://localhost:10000 0 2 2"
+```
+
+Now, the application running in the first terminal window, is identified as running in data center 1 and on rack 2;
+the application in the second terminal window is running in the same data center in a different rack (data center 1, rack 3).
+While, the application in the third terminal is running in a different data center (data center 2).
+
+If you stop the node in the first terminal window (control-c) you will observe that the process in the third terminal window
+takes longer to settle to the correct state then the process in the second terminal window, because it is expecting
+a greater latency in message transmission and is (therefore) more tolerant to delays (and drops) in messaging, taking it
+longer to detect that the killed process is "off line".
+
+Final Notes
+-----------
+
+That concludes the description of running the examples.
+
+This project is an Apache [incubator project](http://incubator.apache.org/projects/gossip.html).
+The [official web site](http://gossip.incubator.apache.org/community/) has much additional information:
+see especially 'get involved' under 'community'. Enjoy, and please let us know if you are finding this library helpful in any way.
+
diff --git a/gossip-examples/pom.xml b/gossip-examples/pom.xml
new file mode 100644
index 0000000..2246eba
--- /dev/null
+++ b/gossip-examples/pom.xml
@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor
+ license agreements. See the NOTICE file distributed with this work for additional
+ information regarding copyright ownership. The ASF licenses this file to
+ You under the Apache License, Version 2.0 (the "License"); you may not use
+ this file except in compliance with the License. You may obtain a copy of
+ the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required
+ by applicable law or agreed to in writing, software distributed under the
+ License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
+ OF ANY KIND, either express or implied. See the License for the specific
+ language governing permissions and limitations under the License. -->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+ <modelVersion>4.0.0</modelVersion>
+
+ <parent>
+ <groupId>org.apache.gossip</groupId>
+ <artifactId>gossip-parent</artifactId>
+ <version>0.1.3-incubating-SNAPSHOT</version>
+ </parent>
+
+ <name>Gossip Examples</name>
+ <artifactId>gossip-examples</artifactId>
+
+ <version>0.1.3-incubating-SNAPSHOT</version>
+
+ <dependencies>
+ <dependency>
+ <groupId>org.apache.gossip</groupId>
+ <artifactId>gossip-base</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>org.apache.gossip</groupId>
+ <artifactId>gossip-protocol-jackson</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>org.apache.gossip</groupId>
+ <artifactId>gossip-transport-udp</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ </dependencies>
+
+</project>
\ No newline at end of file
diff --git a/gossip-examples/src/main/java/org/apache/gossip/examples/ExampleCommon.java b/gossip-examples/src/main/java/org/apache/gossip/examples/ExampleCommon.java
new file mode 100644
index 0000000..279bff1
--- /dev/null
+++ b/gossip-examples/src/main/java/org/apache/gossip/examples/ExampleCommon.java
@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gossip.examples;
+
+public class ExampleCommon {
+
+ private boolean clearTerminalScreen = true;
+
+ /*
+ * Look for -s in args. If there, suppress terminal-clear on write results Shift args for
+ * positional args, if necessary
+ */
+ public String[] checkArgsForClearFlag(String[] args) {
+ int pos = 0;
+ for (int i = 0; i < args.length; i++) {
+ if (args[i].equals("-s")) {
+ clearTerminalScreen = false;
+ } else {
+ // in the case of the -s flag, shift args
+ // down by one slot; this will end up with
+ // a duplicate entry in the last position of args,
+ // but this is ok, because it will be ignored
+ args[pos++] = args[i];
+ }
+ }
+ return args;
+ }
+
+ public void optionallyClearTerminal() {
+ if (clearTerminalScreen) {
+ System.out.print("\033[H\033[2J");
+ System.out.flush();
+ }
+ }
+}
diff --git a/gossip-base/src/main/java/org/apache/gossip/examples/StandAloneDatacenterAndRack.java b/gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneDatacenterAndRack.java
similarity index 82%
rename from gossip-base/src/main/java/org/apache/gossip/examples/StandAloneDatacenterAndRack.java
rename to gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneDatacenterAndRack.java
index 497894c..1a2643c 100644
--- a/gossip-base/src/main/java/org/apache/gossip/examples/StandAloneDatacenterAndRack.java
+++ b/gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneDatacenterAndRack.java
@@ -32,7 +32,10 @@
public class StandAloneDatacenterAndRack {
- public static void main (String [] args) throws UnknownHostException, InterruptedException {
+ private static ExampleCommon common = new ExampleCommon();
+
+ public static void main(String[] args) throws UnknownHostException, InterruptedException {
+ args = common.checkArgsForClearFlag(args);
GossipSettings s = new GossipSettings();
s.setWindowSize(1000);
s.setGossipInterval(100);
@@ -44,19 +47,21 @@
Map<String, String> props = new HashMap<>();
props.put(DatacenterRackAwareActiveGossiper.DATACENTER, args[4]);
props.put(DatacenterRackAwareActiveGossiper.RACK, args[5]);
- GossipManager manager = GossipManagerBuilder.newBuilder()
- .cluster("mycluster")
+ GossipManager manager = GossipManagerBuilder.newBuilder().cluster("mycluster")
.uri(URI.create(args[0]))
.id(args[1])
.gossipSettings(s)
- .gossipMembers(Arrays.asList(new RemoteMember("mycluster", URI.create(args[2]), args[3])))
+ .gossipMembers(
+ Arrays.asList(new RemoteMember("mycluster", URI.create(args[2]), args[3])))
.properties(props)
.build();
manager.init();
- while (true){
+ while (true) {
+ common.optionallyClearTerminal();
System.out.println("Live: " + manager.getLiveMembers());
System.out.println("Dead: " + manager.getDeadMembers());
Thread.sleep(2000);
}
}
+
}
diff --git a/gossip-base/src/main/java/org/apache/gossip/examples/StandAloneNode.java b/gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneNode.java
similarity index 79%
rename from gossip-base/src/main/java/org/apache/gossip/examples/StandAloneNode.java
rename to gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneNode.java
index 93421b1..70c3e4d 100644
--- a/gossip-base/src/main/java/org/apache/gossip/examples/StandAloneNode.java
+++ b/gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneNode.java
@@ -26,22 +26,28 @@
import org.apache.gossip.manager.GossipManagerBuilder;
public class StandAloneNode {
- public static void main (String [] args) throws UnknownHostException, InterruptedException{
+
+ private static ExampleCommon common = new ExampleCommon();
+
+ public static void main(String[] args) throws UnknownHostException, InterruptedException {
+ args = common.checkArgsForClearFlag(args);
GossipSettings s = new GossipSettings();
s.setWindowSize(1000);
s.setGossipInterval(100);
- GossipManager gossipService = GossipManagerBuilder.newBuilder()
- .cluster("mycluster")
+ GossipManager gossipService = GossipManagerBuilder.newBuilder().cluster("mycluster")
.uri(URI.create(args[0]))
.id(args[1])
- .gossipMembers(Arrays.asList( new RemoteMember("mycluster", URI.create(args[2]), args[3])))
+ .gossipMembers(
+ Arrays.asList(new RemoteMember("mycluster", URI.create(args[2]), args[3])))
.gossipSettings(s)
.build();
gossipService.init();
- while (true){
+ while (true) {
+ common.optionallyClearTerminal();
System.out.println("Live: " + gossipService.getLiveMembers());
System.out.println("Dead: " + gossipService.getDeadMembers());
Thread.sleep(2000);
}
}
+
}
diff --git a/gossip-base/src/main/java/org/apache/gossip/examples/StandAloneNodeCrdtOrSet.java b/gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneNodeCrdtOrSet.java
similarity index 71%
rename from gossip-base/src/main/java/org/apache/gossip/examples/StandAloneNodeCrdtOrSet.java
rename to gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneNodeCrdtOrSet.java
index d78cf5e..7d4db93 100644
--- a/gossip-base/src/main/java/org/apache/gossip/examples/StandAloneNodeCrdtOrSet.java
+++ b/gossip-examples/src/main/java/org/apache/gossip/examples/StandAloneNodeCrdtOrSet.java
@@ -31,56 +31,62 @@
import org.apache.gossip.model.SharedDataMessage;
public class StandAloneNodeCrdtOrSet {
- public static void main (String [] args) throws InterruptedException, IOException{
+
+ private static ExampleCommon common = new ExampleCommon();
+
+ public static void main(String[] args) throws InterruptedException, IOException {
+ args = common.checkArgsForClearFlag(args);
GossipSettings s = new GossipSettings();
s.setWindowSize(1000);
s.setGossipInterval(100);
- GossipManager gossipService = GossipManagerBuilder.newBuilder()
- .cluster("mycluster")
+ GossipManager gossipService = GossipManagerBuilder.newBuilder().cluster("mycluster")
.uri(URI.create(args[0]))
.id(args[1])
- .gossipMembers(Arrays.asList( new RemoteMember("mycluster", URI.create(args[2]), args[3])))
+ .gossipMembers(
+ Arrays.asList(new RemoteMember("mycluster", URI.create(args[2]), args[3])))
.gossipSettings(s)
.build();
gossipService.init();
-
+
new Thread(() -> {
- while (true){
- System.out.println("Live: " + gossipService.getLiveMembers());
- System.out.println("Dead: " + gossipService.getDeadMembers());
- System.out.println("---------- " + (gossipService.findCrdt("abc") == null ? "":
- gossipService.findCrdt("abc").value()));
- System.out.println("********** " + gossipService.findCrdt("abc"));
- System.out.println("^^^^^^^^^^ " + (gossipService.findCrdt("def") == null ? "":
- gossipService.findCrdt("def").value()));
- System.out.println("$$$$$$$$$$ " + gossipService.findCrdt("def"));
- try {
- Thread.sleep(2000);
- } catch (Exception e) {}
+ while (true) {
+ common.optionallyClearTerminal();
+ System.out.println("Live: " + gossipService.getLiveMembers());
+ System.out.println("Dead: " + gossipService.getDeadMembers());
+ System.out.println("---------- " + (gossipService.findCrdt("abc") == null ? ""
+ : gossipService.findCrdt("abc").value()));
+ System.out.println("********** " + gossipService.findCrdt("abc"));
+ System.out.println("^^^^^^^^^^ " + (gossipService.findCrdt("def") == null ? ""
+ : gossipService.findCrdt("def").value()));
+ System.out.println("$$$$$$$$$$ " + gossipService.findCrdt("def"));
+ try {
+ Thread.sleep(2000);
+ } catch (Exception e) {
+ }
}
}).start();
-
+
String line = null;
- try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))){
- while ( (line = br.readLine()) != null){
+ try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
+ while ((line = br.readLine()) != null) {
System.out.println(line);
char op = line.charAt(0);
String val = line.substring(2);
- if (op == 'a'){
+ if (op == 'a') {
addData(val, gossipService);
} else if (op == 'r') {
removeData(val, gossipService);
- } else if (op == 'g'){
+ } else if (op == 'g') {
gcount(val, gossipService);
}
}
}
}
-
- private static void gcount(String val, GossipManager gossipManager){
+
+ private static void gcount(String val, GossipManager gossipManager) {
GrowOnlyCounter c = (GrowOnlyCounter) gossipManager.findCrdt("def");
Long l = Long.valueOf(val);
- if (c == null){
+ if (c == null) {
c = new GrowOnlyCounter(new GrowOnlyCounter.Builder(gossipManager).increment((l)));
} else {
c = new GrowOnlyCounter(c, new GrowOnlyCounter.Builder(gossipManager).increment((l)));
@@ -92,19 +98,19 @@
m.setTimestamp(System.currentTimeMillis());
gossipManager.merge(m);
}
-
- private static void removeData(String val, GossipManager gossipService){
+
+ private static void removeData(String val, GossipManager gossipService) {
@SuppressWarnings("unchecked")
OrSet<String> s = (OrSet<String>) gossipService.findCrdt("abc");
SharedDataMessage m = new SharedDataMessage();
m.setExpireAt(Long.MAX_VALUE);
m.setKey("abc");
- m.setPayload(new OrSet<String>(s , new OrSet.Builder<String>().remove(val)));
+ m.setPayload(new OrSet<String>(s, new OrSet.Builder<String>().remove(val)));
m.setTimestamp(System.currentTimeMillis());
gossipService.merge(m);
}
-
- private static void addData(String val, GossipManager gossipService){
+
+ private static void addData(String val, GossipManager gossipService) {
SharedDataMessage m = new SharedDataMessage();
m.setExpireAt(Long.MAX_VALUE);
m.setKey("abc");
@@ -112,4 +118,5 @@
m.setTimestamp(System.currentTimeMillis());
gossipService.merge(m);
}
+
}
diff --git a/gossip-itest/.gitignore b/gossip-itest/.gitignore
new file mode 100644
index 0000000..f538c88
--- /dev/null
+++ b/gossip-itest/.gitignore
@@ -0,0 +1,5 @@
+# json files generated with running examples in this module
+pernodedata.*.*.json
+ringstate.*.*.json
+shareddata.*.*.json
+
diff --git a/pom.xml b/pom.xml
index 1c48306..8740319 100644
--- a/pom.xml
+++ b/pom.xml
@@ -59,6 +59,7 @@
<module>gossip-transport-udp</module>
<module>gossip-protocol-jackson</module>
<module>gossip-itest</module>
+ <module>gossip-examples</module>
</modules>
<description>A peer to peer cluster discovery service</description>
@@ -195,8 +196,10 @@
<artifactId>apache-rat-plugin</artifactId>
<configuration>
<excludes>
- <exclude>README.md</exclude>
+ <exclude>**/README.md</exclude>
<exclude>eclipse_template.xml</exclude>
+ <!-- files generated by running the examples in gossip-examples -->
+ <exclued>**/*.mycluster.*.json</exclued>
</excludes>
</configuration>
<executions>
