├── .gitignore
├── .mvn
    └── wrapper
    │   ├── maven-wrapper.jar
    │   └── maven-wrapper.properties
├── Dockerfile
├── LICENSE
├── README.md
├── bin
    ├── entrypoint.sh
    ├── logging.properties
    └── management.properties
├── doc
    ├── images
    │   ├── jconsole_01_start.png
    │   ├── jconsole_02_address.png
    │   ├── jconsole_03_insecure.png
    │   └── jconsole_04_graph.png
    └── jconsole.md
├── docker-compose.yml
├── mvnw
├── mvnw.cmd
├── pom.xml
└── src
    └── main
        ├── java
            └── com
            │   └── github
            │       └── cstroe
            │           └── loopapp
            │               └── Main.java
        └── resources
            └── log4j2.xml


/.gitignore:
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1 | .idea/
2 | *.iml
3 | 
4 | target/
5 | 


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/.mvn/wrapper/maven-wrapper.jar:
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/.mvn/wrapper/maven-wrapper.properties:
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1 | distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.3.9/apache-maven-3.3.9-bin.zip


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/Dockerfile:
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 1 | FROM openjdk:8-jdk
 2 | 
 3 | # to check for open ports in the container: docker run <container id> netstat -tan
 4 | #RUN apt update && apt install net-tools
 5 | 
 6 | RUN mkdir -p /opt/app
 7 | 
 8 | # An executable jar that will run in this Docker container
 9 | # Run `mvn package` to create it
10 | ADD target/sample-app.jar /opt/app/app.jar
11 | 
12 | # A simple shell script to pass JVM arguments
13 | ADD bin/entrypoint.sh /opt/app/entrypoint.sh
14 | 
15 | # JMX
16 | EXPOSE 9010
17 | 
18 | # JVM debugging port
19 | EXPOSE 5005
20 | 
21 | ENTRYPOINT [ "/opt/app/entrypoint.sh" ]
22 | 


--------------------------------------------------------------------------------
/LICENSE:
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/README.md:
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  1 | # Java JMX with Docker
  2 | 
  3 | The purpose of this project is to present the configuration settings required to expose a JMX port from a JVM running inside a Docker container.
  4 | 
  5 | Docker requires ports to be declared before the application runs.  This conflicts with JMX over RMI (the default JMX protocol), which relies on establishing communication using random ports negotiated at connection time.  The randomly negotiated JMX ports can't be declared in the Docker config, causing JMX connections to fail.
  6 | 
  7 | If connecting from another container linked to the JVM container (same Docker network) then all ports will be accessible, including the randomly negotiated ones.  However, the typical use case for JMX monitoring is to connect from outside the docker network (via mapping to a host port).
  8 | 
  9 | We get around these limitations with careful configuration of the JMX properties.  The main tricks:
 10 | * set `com.sun.management.jmxremote.port` and `com.sun.management.jmxremote.rmi.port` to the exposed port, in our case `9010`, and
 11 | * set `com.sun.management.jmxremote.host` and `java.rmi.server.hostname` to the [catch-all IP address](https://en.wikipedia.org/wiki/0.0.0.0) `0.0.0.0`.
 12 | 
 13 | TL;DR -- [entrypoint.sh](https://github.com/cstroe/java-jmx-in-docker-sample-app/blob/master/bin/entrypoint.sh)
 14 | 
 15 | ## Usage
 16 | 
 17 |     ./mvnw package
 18 |     docker-compose up --build
 19 | 
 20 | [Docker Compose](https://docs.docker.com/compose/install/) will start the application and expose port 9010 as a JMX port on the docker host.
 21 | 
 22 | Using [jconsole](doc/jconsole.md) or [VisualVM](https://visualvm.github.io/), you can connect to `localhost:9010`.
 23 | 
 24 | ## Notes
 25 | 
 26 | The goal of this configuration is to connect with a JMX/RMI client
 27 | from outside of the Docker internal network, usually via a port
 28 | mapped to a host port. 
 29 | 
 30 | The RMI transport is included with the JVM, and therefore is supported
 31 | by all the JMX clients (JConsole, VisualVM, etc).
 32 | 
 33 | Here are some considerations when setting the JVM arguments:
 34 | 
 35 | 1. `com.sun.management.jmxremote.port` and `com.sun.management.jmxremote.rmi.port`
 36 | 
 37 |    These properties are set to the same value for convenience.
 38 |    They don't have to be the same, but you have to expose one
 39 |    extra port if they're not equal.
 40 | 
 41 |    If you _don't_ declare the RMI port, the RMI protocol will choose
 42 |    a ***random port*** at connection time after the initial handshake.
 43 |    This will cause the JMX client to hang as the port will not
 44 |    be externally accessible.
 45 | 
 46 | 2. `com.sun.management.jmxremote.host`
 47 | 
 48 |    This property is required if `java.rmi.server.hostname` is not set
 49 |    and represents the externally accessible hostname or IP of the
 50 |    JVM, used as part of the JmxConnectorUrl. If ConnectorBootstrap
 51 |    logging is enabled, the URL will be printed at JVM startup:
 52 | 
 53 |    > CONFIG: JMX Connector ready at: service:jmx:rmi:///jndi/rmi://172.18.0.2:9010/jmxrmi
 54 | 
 55 |    When running in Docker this hostname or IP should be
 56 |    externally accessible. The value is usually passed into
 57 |    the container through an environment variable, as Docker
 58 |    provides no mechanism for looking up the Docker host's
 59 |    hostname or IP.
 60 | 
 61 |    If neither this property nor `java.rmi.server.hostname` are set, you
 62 |    will get this error at JVM startup:
 63 | 
 64 |    > Error: Exception thrown by the agent : java.net.MalformedURLException: Cannot give port number without host name
 65 | 
 66 |    In our case, we set the host to `0.0.0.0` for the JVM to listen on any available interface.
 67 | 
 68 | 3. `java.util.logging.config.file`
 69 | 
 70 |    The optional path to a [logging.properties](bin/logging.properties) file
 71 |    that configures the Java Logging framework to print RMI debugging messages.
 72 | 
 73 |    Example logging output:
 74 | 
 75 |    > Mar 23, 2017 8:56:26 AM ConnectorBootstrap startRemoteConnectorServer
 76 |    > FINEST: Starting JMX Connector Server:
 77 |    > 	com.sun.management.jmxremote.port=9010
 78 |    > 	com.sun.management.jmxremote.host=0.0.0.0
 79 |    > 	com.sun.management.jmxremote.rmi.port=9010
 80 |    > 	com.sun.management.jmxremote.ssl=false
 81 |    > 	com.sun.management.jmxremote.registry.ssl=false
 82 |    > 	com.sun.management.jmxremote.ssl.config.file=null
 83 |    > 	com.sun.management.jmxremote.ssl.enabled.cipher.suites=null
 84 |    > 	com.sun.management.jmxremote.ssl.enabled.protocols=null
 85 |    > 	com.sun.management.jmxremote.ssl.need.client.auth=false
 86 |    > 	com.sun.management.jmxremote.authenticate=false
 87 |    > 	No Authentication
 88 |    > Mar 23, 2017 8:56:26 AM ConnectorBootstrap startRemoteConnectorServer
 89 |    > CONFIG: JMX Connector ready at: service:jmx:rmi:///jndi/rmi://0.0.0.0:9010/jmxrmi
 90 |    
 91 |    JMX logging configuration happens early in the JVM startup and
 92 |    uses the Java Logging framework.  This logging is useful for debugging purposes.
 93 | 
 94 | 4. `com.sun.management.config.file`
 95 | 
 96 |    This optional configuration option points to a file that
 97 |    is read in by ConnectorBootstrap at startup time
 98 |    to set `com.sun.management.jmxremote.*` properties.
 99 |    However, since no environment variable substitution is done
100 |    any properties that must be set via environment variables
101 |    cannot be specified in that file, and must be passed from this
102 |    shell script (see below).
103 |    
104 |    The properties in the [management.properties](bin/management.properties)
105 |    file can be passed directly to the JVM as command line arguments.
106 |    See [entrypoint.sh](bin/entrypoint.sh).
107 | 
108 | 5. `java.rmi.server.hostname`
109 | 
110 |    This is a critical property when using JMX with a JVM running 
111 |    inside a Docker container.  It should be set to
112 |    the externally accessible hostname or IP of the Docker container,
113 |    same as `com.sun.management.jmxremote.host`.
114 | 
115 |    ***If this property is incorrect (or not set) all JMX connections will fail!***
116 | 
117 |    In our case, we use the catch-all IP `0.0.0.0` to have the JVM
118 |    listen on any available address.  This avoids us having to specify
119 |    the host IP of the Docker machine, and requires no further special
120 |    configuration.
121 | 
122 | ## Links
123 | 
124 | ### GitHub
125 | 
126 | * [oracle/docker-images](https://github.com/oracle/docker-images/tree/master/OracleCoherence/docs/5.monitoring) - Very informative, talks about JMXMP too.
127 | * [nolexa/docker-jmx-demo](https://github.com/nolexa/docker-jmx-demo) - Explains the same thing as this repository.
128 | * [gimerstedt/jmx-to-spring-boot-in-docker](https://github.com/gimerstedt/jmx-to-spring-boot-in-docker) - Spring Boot centric
129 | * [zacker330/Java-JMX-example](https://github.com/zacker330/Java-JMX-example) - adds simple authentication, Jolokia agent
130 | * [jolokia/jolokia](https://github.com/jolokia/jolokia) - a JVM agent that uses JSON over HTTP, instead of RMI, has other [features](https://jolokia.org/features-nb.html)
131 | * [prometheus/jmx\_exporter](https://github.com/prometheus/jmx_exporter) - a JVM agent that exposes JMX metrics for [Prometheus](https://github.com/prometheus/prometheus)
132 | 
133 | ### Blog Posts
134 | 
135 | * [JMX Ports (Baeldung)](https://www.baeldung.com/jmx-ports) - for local apps not Docker, also describes `-XX:+DisableAttachMechanism` and `com.sun.management.jmxremote`
136 | * [Remote Java Debugging With Docker](https://ptmccarthy.github.io/2014/07/24/remote-jmx-with-docker/)
137 | * [Monitoring Java Applications Running Inside Docker Containers](http://www.jamasoftware.com/blog/monitoring-java-applications/)
138 | * [Monitoring JVM apps in a Docker environment](http://mintbeans.com/jvm-monitoring-docker/)
139 | * [JMX Monitoring with Docker and the ELK Stack](https://www.ivankrizsan.se/2015/09/27/jmx-monitoring-with-the-elk-stack/)
140 | * [How to connect VisualVM to Docker](http://www.ethanjoachimeldridge.info/tech-blog/connect-visualvm-docker)
141 | * [JMX: RMI vs. JMXMP](https://meteatamel.wordpress.com/2012/02/13/jmx-rmi-vs-jmxmp/) - Outdated, but talks about why JMXMP fits better with Docker
142 | 
143 | ### Forums
144 | 
145 | * https://forums.docker.com/t/enable-jmx-rmi-access-to-a-docker-container/625/5
146 | 
147 | ### StackOverflow
148 | 
149 | * [Why Java opens 3 ports when JMX is configured?](https://stackoverflow.com/questions/20884353/why-java-opens-3-ports-when-jmx-is-configured)
150 | * [How to activate JMX on my JVM for access with jconsole?](http://stackoverflow.com/questions/856881/how-to-activate-jmx-on-my-jvm-for-access-with-jconsole)
151 | * [How to access JMX interface in docker from outside?](http://stackoverflow.com/questions/31257968/how-to-access-jmx-interface-in-docker-from-outside)
152 | * [Access through jmx to java application into Docker container on remote host in local network](http://serverfault.com/questions/789976/access-through-jmx-to-java-application-into-docker-container-on-remote-host-in-l) - Very concise explanation of using JMXMP
153 | * [multiple app nodes how to expose jmx in kubernetes?](https://stackoverflow.com/questions/35184558/multiple-app-nodes-how-to-expose-jmx-in-kubernetes/39927197#39927197)
154 | * [Profiling Java application in kubernetes](https://stackoverflow.com/questions/41720185/profiling-java-application-in-kubernetes?noredirect=1&lq=1)
155 | * [JConsole over ssh local port forwarding](https://stackoverflow.com/questions/15093376/jconsole-over-ssh-local-port-forwarding)
156 | * [How to use VisualVM and JMX?](https://stackoverflow.com/questions/30104142/how-to-use-visualvm-and-jmx)
157 | 
158 | ### YouTube
159 | 
160 | * [Using JMX to monitor an Application Server running on Docker](https://www.youtube.com/watch?v=tVL3hkA149o) - This video sets `java.rmi.server.hostname` to the Docker host IP address, which is not what we recommend in this repo.  It's also using some specific Dell JMX web interface.  Consider removing this link.
161 | 
162 | ### Other documentation
163 | 
164 | * [confluent](http://docs.confluent.io/3.0.1/cp-docker-images/docs/operations/monitoring.html#using-jmx)
165 | * [Oracle Guide](https://docs.oracle.com/javase/8/docs/technotes/guides/management/agent.html)
166 | 


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/bin/entrypoint.sh:
--------------------------------------------------------------------------------
 1 | #!/usr/bin/env bash
 2 | set -x
 3 | 
 4 | JMX_PORT=9010
 5 | HOST="0.0.0.0"
 6 | 
 7 | java \
 8 |   -Dsun.management.jmxremote.level=FINEST \
 9 |   -Dsun.management.jmxremote.handlers=java.util.logging.ConsoleHandler \
10 |   -Djava.util.logging.ConsoleHandler.level=FINEST \
11 |   -Dcom.sun.management.jmxremote.local.only=false \
12 |   -Dcom.sun.management.jmxremote.ssl=false \
13 |   -Dcom.sun.management.jmxremote.authenticate=false \
14 |   -Dcom.sun.management.jmxremote.port=$JMX_PORT \
15 |   -Dcom.sun.management.jmxremote.rmi.port=$JMX_PORT \
16 |   -Dcom.sun.management.jmxremote.host=$HOST \
17 |   -Djava.rmi.server.hostname=$HOST \
18 |   -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005 \
19 |   -jar /opt/app/app.jar
20 | 
21 | 


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/bin/logging.properties:
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1 | sun.management.jmxremote.level = FINEST
2 | sun.management.jmxremote.handlers = java.util.logging.ConsoleHandler
3 | java.util.logging.ConsoleHandler.level = FINEST


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/bin/management.properties:
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1 | com.sun.management.jmxremote.port=9010
2 | com.sun.management.jmxremote.local.only=false
3 | com.sun.management.jmxremote.ssl=false
4 | com.sun.management.jmxremote.authenticate=false
5 | com.sun.management.jmxremote.host=eth0
6 | com.sun.management.jmxremote.rmi.port=9010


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https://raw.githubusercontent.com/cstroe/java-jmx-in-docker-sample-app/39f472d688e97e2583ecc76128cd10560022343d/doc/images/jconsole_04_graph.png


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/doc/jconsole.md:
--------------------------------------------------------------------------------
 1 | # Using JConsole to connect to an application via JMX
 2 | 
 3 | NOTE: The shell commands are for a \*nix operating system (Linux, \*BSD, etc...).  The GUI steps should be the same for all operating systems.
 4 | 
 5 | ## Installation
 6 | 
 7 | The `jconsole` application is included with any JDK (Java Development Kit).  If you have the `JAVA_HOME` environment variable set, you can verify this with:
 8 | 
 9 | ```shell
10 | ls -la $JAVA_HOME/bin/jconsole
11 | ```
12 | 
13 | Otherwise, you can verify with:
14 | 
15 | ```shell
16 | which jconsole
17 | ```
18 | 
19 | If you don't have a JDK installed, there usually exist instructions for your operating system to install a JDK.  Installing a JRE (Java Runtime Environment) is not enough, as it doesn't include `jconsole`.
20 | 
21 | ## Connect to application via JMX
22 | 
23 | First, start JConsole by running the binary:
24 | 
25 | ```shell
26 | jconsole
27 | ```
28 | 
29 | This will bring up the initial jconsole window:
30 | 
31 | ![Screenshot of the window shown when jconsole initially starts.  A panel titled "JConsole: New Connection" is shown.](images/jconsole_01_start.png)
32 | 
33 | Click into the "Remote Process" field and enter the address of your JMX port, in our case `localhost:9010`.
34 | Since we have not setup any authentication, we don't need to enter a username or password.
35 | Then click the "Connect" button to start the connection.
36 | 
37 | ![Screenshot of entering the remote address in the JConsole New Connection panel.](images/jconsole_02_address.png)
38 | 
39 | 
40 | JConsole will warn you about the insecure connection.  Just click the "Insecure connection" button to proceed.
41 | 
42 | ![Screenshot of the insecure connection warning dialog, with two buttons, "Cancel" and "Insecure connection".](images/jconsole_03_insecure.png)
43 | 
44 | Finally, at this point JConsole will start reading JVM metrics over JMX.  On the main screen you can see memory, threads, classes, and CPU usage:
45 | 
46 | ![Screenshot of the default graphs shown by jconsole after connecting to a running JVM process, including memory, threads, classes, and CPU usage.](images/jconsole_04_graph.png)
47 | 
48 | ## Links
49 | 
50 | * More info about JConsole: [OpenJDK JConsole](http://openjdk.java.net/tools/svc/jconsole/)
51 | 


--------------------------------------------------------------------------------
/docker-compose.yml:
--------------------------------------------------------------------------------
1 | version: "2"
2 | services:
3 |   loop:
4 |     build: .
5 |     ports:
6 |       - "9010:9010"
7 |       - "5005:5005"
8 | 


--------------------------------------------------------------------------------
/mvnw:
--------------------------------------------------------------------------------
  1 | #!/bin/sh
  2 | # ----------------------------------------------------------------------------
  3 | # Licensed to the Apache Software Foundation (ASF) under one
  4 | # or more contributor license agreements.  See the NOTICE file
  5 | # distributed with this work for additional information
  6 | # regarding copyright ownership.  The ASF licenses this file
  7 | # to you under the Apache License, Version 2.0 (the
  8 | # "License"); you may not use this file except in compliance
  9 | # with the License.  You may obtain a copy of the License at
 10 | #
 11 | #    http://www.apache.org/licenses/LICENSE-2.0
 12 | #
 13 | # Unless required by applicable law or agreed to in writing,
 14 | # software distributed under the License is distributed on an
 15 | # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 16 | # KIND, either express or implied.  See the License for the
 17 | # specific language governing permissions and limitations
 18 | # under the License.
 19 | # ----------------------------------------------------------------------------
 20 | 
 21 | # ----------------------------------------------------------------------------
 22 | # Maven2 Start Up Batch script
 23 | #
 24 | # Required ENV vars:
 25 | # ------------------
 26 | #   JAVA_HOME - location of a JDK home dir
 27 | #
 28 | # Optional ENV vars
 29 | # -----------------
 30 | #   M2_HOME - location of maven2's installed home dir
 31 | #   MAVEN_OPTS - parameters passed to the Java VM when running Maven
 32 | #     e.g. to debug Maven itself, use
 33 | #       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
 34 | #   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
 35 | # ----------------------------------------------------------------------------
 36 | 
 37 | if [ -z "$MAVEN_SKIP_RC" ] ; then
 38 | 
 39 |   if [ -f /etc/mavenrc ] ; then
 40 |     . /etc/mavenrc
 41 |   fi
 42 | 
 43 |   if [ -f "$HOME/.mavenrc" ] ; then
 44 |     . "$HOME/.mavenrc"
 45 |   fi
 46 | 
 47 | fi
 48 | 
 49 | # OS specific support.  $var _must_ be set to either true or false.
 50 | cygwin=false;
 51 | darwin=false;
 52 | mingw=false
 53 | case "`uname`" in
 54 |   CYGWIN*) cygwin=true ;;
 55 |   MINGW*) mingw=true;;
 56 |   Darwin*) darwin=true
 57 |            #
 58 |            # Look for the Apple JDKs first to preserve the existing behaviour, and then look
 59 |            # for the new JDKs provided by Oracle.
 60 |            #
 61 |            if [ -z "$JAVA_HOME" ] && [ -L /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK ] ; then
 62 |              #
 63 |              # Apple JDKs
 64 |              #
 65 |              export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home
 66 |            fi
 67 | 
 68 |            if [ -z "$JAVA_HOME" ] && [ -L /System/Library/Java/JavaVirtualMachines/CurrentJDK ] ; then
 69 |              #
 70 |              # Apple JDKs
 71 |              #
 72 |              export JAVA_HOME=/System/Library/Java/JavaVirtualMachines/CurrentJDK/Contents/Home
 73 |            fi
 74 | 
 75 |            if [ -z "$JAVA_HOME" ] && [ -L "/Library/Java/JavaVirtualMachines/CurrentJDK" ] ; then
 76 |              #
 77 |              # Oracle JDKs
 78 |              #
 79 |              export JAVA_HOME=/Library/Java/JavaVirtualMachines/CurrentJDK/Contents/Home
 80 |            fi
 81 | 
 82 |            if [ -z "$JAVA_HOME" ] && [ -x "/usr/libexec/java_home" ]; then
 83 |              #
 84 |              # Apple JDKs
 85 |              #
 86 |              export JAVA_HOME=`/usr/libexec/java_home`
 87 |            fi
 88 |            ;;
 89 | esac
 90 | 
 91 | if [ -z "$JAVA_HOME" ] ; then
 92 |   if [ -r /etc/gentoo-release ] ; then
 93 |     JAVA_HOME=`java-config --jre-home`
 94 |   fi
 95 | fi
 96 | 
 97 | if [ -z "$M2_HOME" ] ; then
 98 |   ## resolve links - $0 may be a link to maven's home
 99 |   PRG="$0"
100 | 
101 |   # need this for relative symlinks
102 |   while [ -h "$PRG" ] ; do
103 |     ls=`ls -ld "$PRG"`
104 |     link=`expr "$ls" : '.*-> \(.*\)$'`
105 |     if expr "$link" : '/.*' > /dev/null; then
106 |       PRG="$link"
107 |     else
108 |       PRG="`dirname "$PRG"`/$link"
109 |     fi
110 |   done
111 | 
112 |   saveddir=`pwd`
113 | 
114 |   M2_HOME=`dirname "$PRG"`/..
115 | 
116 |   # make it fully qualified
117 |   M2_HOME=`cd "$M2_HOME" && pwd`
118 | 
119 |   cd "$saveddir"
120 |   # echo Using m2 at $M2_HOME
121 | fi
122 | 
123 | # For Cygwin, ensure paths are in UNIX format before anything is touched
124 | if $cygwin ; then
125 |   [ -n "$M2_HOME" ] &&
126 |     M2_HOME=`cygpath --unix "$M2_HOME"`
127 |   [ -n "$JAVA_HOME" ] &&
128 |     JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
129 |   [ -n "$CLASSPATH" ] &&
130 |     CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
131 | fi
132 | 
133 | # For Migwn, ensure paths are in UNIX format before anything is touched
134 | if $mingw ; then
135 |   [ -n "$M2_HOME" ] &&
136 |     M2_HOME="`(cd "$M2_HOME"; pwd)`"
137 |   [ -n "$JAVA_HOME" ] &&
138 |     JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
139 |   # TODO classpath?
140 | fi
141 | 
142 | if [ -z "$JAVA_HOME" ]; then
143 |   javaExecutable="`which javac`"
144 |   if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
145 |     # readlink(1) is not available as standard on Solaris 10.
146 |     readLink=`which readlink`
147 |     if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
148 |       if $darwin ; then
149 |         javaHome="`dirname \"$javaExecutable\"`"
150 |         javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
151 |       else
152 |         javaExecutable="`readlink -f \"$javaExecutable\"`"
153 |       fi
154 |       javaHome="`dirname \"$javaExecutable\"`"
155 |       javaHome=`expr "$javaHome" : '\(.*\)/bin'`
156 |       JAVA_HOME="$javaHome"
157 |       export JAVA_HOME
158 |     fi
159 |   fi
160 | fi
161 | 
162 | if [ -z "$JAVACMD" ] ; then
163 |   if [ -n "$JAVA_HOME"  ] ; then
164 |     if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
165 |       # IBM's JDK on AIX uses strange locations for the executables
166 |       JAVACMD="$JAVA_HOME/jre/sh/java"
167 |     else
168 |       JAVACMD="$JAVA_HOME/bin/java"
169 |     fi
170 |   else
171 |     JAVACMD="`which java`"
172 |   fi
173 | fi
174 | 
175 | if [ ! -x "$JAVACMD" ] ; then
176 |   echo "Error: JAVA_HOME is not defined correctly." >&2
177 |   echo "  We cannot execute $JAVACMD" >&2
178 |   exit 1
179 | fi
180 | 
181 | if [ -z "$JAVA_HOME" ] ; then
182 |   echo "Warning: JAVA_HOME environment variable is not set."
183 | fi
184 | 
185 | CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
186 | 
187 | # traverses directory structure from process work directory to filesystem root
188 | # first directory with .mvn subdirectory is considered project base directory
189 | find_maven_basedir() {
190 |   local basedir=$(pwd)
191 |   local wdir=$(pwd)
192 |   while [ "$wdir" != '/' ] ; do
193 |     if [ -d "$wdir"/.mvn ] ; then
194 |       basedir=$wdir
195 |       break
196 |     fi
197 |     wdir=$(cd "$wdir/.."; pwd)
198 |   done
199 |   echo "${basedir}"
200 | }
201 | 
202 | # concatenates all lines of a file
203 | concat_lines() {
204 |   if [ -f "$1" ]; then
205 |     echo "$(tr -s '\n' ' ' < "$1")"
206 |   fi
207 | }
208 | 
209 | export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-$(find_maven_basedir)}
210 | MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
211 | 
212 | # For Cygwin, switch paths to Windows format before running java
213 | if $cygwin; then
214 |   [ -n "$M2_HOME" ] &&
215 |     M2_HOME=`cygpath --path --windows "$M2_HOME"`
216 |   [ -n "$JAVA_HOME" ] &&
217 |     JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
218 |   [ -n "$CLASSPATH" ] &&
219 |     CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
220 |   [ -n "$MAVEN_PROJECTBASEDIR" ] &&
221 |     MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
222 | fi
223 | 
224 | # Provide a "standardized" way to retrieve the CLI args that will
225 | # work with both Windows and non-Windows executions.
226 | MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
227 | export MAVEN_CMD_LINE_ARGS
228 | 
229 | WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
230 | 
231 | # avoid using MAVEN_CMD_LINE_ARGS below since that would loose parameter escaping in $@
232 | exec "$JAVACMD" \
233 |   $MAVEN_OPTS \
234 |   -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
235 |   "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
236 |   ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"
237 | 


--------------------------------------------------------------------------------
/mvnw.cmd:
--------------------------------------------------------------------------------
  1 | @REM ----------------------------------------------------------------------------
  2 | @REM Licensed to the Apache Software Foundation (ASF) under one
  3 | @REM or more contributor license agreements.  See the NOTICE file
  4 | @REM distributed with this work for additional information
  5 | @REM regarding copyright ownership.  The ASF licenses this file
  6 | @REM to you under the Apache License, Version 2.0 (the
  7 | @REM "License"); you may not use this file except in compliance
  8 | @REM with the License.  You may obtain a copy of the License at
  9 | @REM
 10 | @REM    http://www.apache.org/licenses/LICENSE-2.0
 11 | @REM
 12 | @REM Unless required by applicable law or agreed to in writing,
 13 | @REM software distributed under the License is distributed on an
 14 | @REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 15 | @REM KIND, either express or implied.  See the License for the
 16 | @REM specific language governing permissions and limitations
 17 | @REM under the License.
 18 | @REM ----------------------------------------------------------------------------
 19 | 
 20 | @REM ----------------------------------------------------------------------------
 21 | @REM Maven2 Start Up Batch script
 22 | @REM
 23 | @REM Required ENV vars:
 24 | @REM JAVA_HOME - location of a JDK home dir
 25 | @REM
 26 | @REM Optional ENV vars
 27 | @REM M2_HOME - location of maven2's installed home dir
 28 | @REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
 29 | @REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a key stroke before ending
 30 | @REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
 31 | @REM     e.g. to debug Maven itself, use
 32 | @REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
 33 | @REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
 34 | @REM ----------------------------------------------------------------------------
 35 | 
 36 | @REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
 37 | @echo off
 38 | @REM enable echoing my setting MAVEN_BATCH_ECHO to 'on'
 39 | @if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
 40 | 
 41 | @REM set %HOME% to equivalent of $HOME
 42 | if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
 43 | 
 44 | @REM Execute a user defined script before this one
 45 | if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
 46 | @REM check for pre script, once with legacy .bat ending and once with .cmd ending
 47 | if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
 48 | if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
 49 | :skipRcPre
 50 | 
 51 | @setlocal
 52 | 
 53 | set ERROR_CODE=0
 54 | 
 55 | @REM To isolate internal variables from possible post scripts, we use another setlocal
 56 | @setlocal
 57 | 
 58 | @REM ==== START VALIDATION ====
 59 | if not "%JAVA_HOME%" == "" goto OkJHome
 60 | 
 61 | echo.
 62 | echo Error: JAVA_HOME not found in your environment. >&2
 63 | echo Please set the JAVA_HOME variable in your environment to match the >&2
 64 | echo location of your Java installation. >&2
 65 | echo.
 66 | goto error
 67 | 
 68 | :OkJHome
 69 | if exist "%JAVA_HOME%\bin\java.exe" goto init
 70 | 
 71 | echo.
 72 | echo Error: JAVA_HOME is set to an invalid directory. >&2
 73 | echo JAVA_HOME = "%JAVA_HOME%" >&2
 74 | echo Please set the JAVA_HOME variable in your environment to match the >&2
 75 | echo location of your Java installation. >&2
 76 | echo.
 77 | goto error
 78 | 
 79 | @REM ==== END VALIDATION ====
 80 | 
 81 | :init
 82 | 
 83 | set MAVEN_CMD_LINE_ARGS=%MAVEN_CONFIG% %*
 84 | 
 85 | @REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
 86 | @REM Fallback to current working directory if not found.
 87 | 
 88 | set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
 89 | IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
 90 | 
 91 | set EXEC_DIR=%CD%
 92 | set WDIR=%EXEC_DIR%
 93 | :findBaseDir
 94 | IF EXIST "%WDIR%"\.mvn goto baseDirFound
 95 | cd ..
 96 | IF "%WDIR%"=="%CD%" goto baseDirNotFound
 97 | set WDIR=%CD%
 98 | goto findBaseDir
 99 | 
100 | :baseDirFound
101 | set MAVEN_PROJECTBASEDIR=%WDIR%
102 | cd "%EXEC_DIR%"
103 | goto endDetectBaseDir
104 | 
105 | :baseDirNotFound
106 | set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
107 | cd "%EXEC_DIR%"
108 | 
109 | :endDetectBaseDir
110 | 
111 | IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
112 | 
113 | @setlocal EnableExtensions EnableDelayedExpansion
114 | for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
115 | @endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
116 | 
117 | :endReadAdditionalConfig
118 | 
119 | SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
120 | 
121 | set WRAPPER_JAR=""%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar""
122 | set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
123 | 
124 | # avoid using MAVEN_CMD_LINE_ARGS below since that would loose parameter escaping in %*
125 | %MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
126 | if ERRORLEVEL 1 goto error
127 | goto end
128 | 
129 | :error
130 | set ERROR_CODE=1
131 | 
132 | :end
133 | @endlocal & set ERROR_CODE=%ERROR_CODE%
134 | 
135 | if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
136 | @REM check for post script, once with legacy .bat ending and once with .cmd ending
137 | if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
138 | if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
139 | :skipRcPost
140 | 
141 | @REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
142 | if "%MAVEN_BATCH_PAUSE%" == "on" pause
143 | 
144 | if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
145 | 
146 | exit /B %ERROR_CODE%
147 | 


--------------------------------------------------------------------------------
/pom.xml:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="UTF-8"?>
 2 | <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 3 | 	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 4 | 	<modelVersion>4.0.0</modelVersion>
 5 | 
 6 | 	<groupId>com.github.cstroe</groupId>
 7 | 	<artifactId>java-jmx-in-docker-sample-app</artifactId>
 8 | 	<version>0.0.1-SNAPSHOT</version>
 9 | 	<packaging>jar</packaging>
10 | 
11 | 	<properties>
12 | 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
13 | 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
14 | 		<java.version>1.8</java.version>
15 | 	</properties>
16 | 
17 |     <build>
18 |         <finalName>sample-app</finalName>
19 |         <plugins>
20 |             <plugin>
21 |                 <!-- Tell Maven to use Java 8 for our source code -->
22 |                 <groupId>org.apache.maven.plugins</groupId>
23 |                 <artifactId>maven-compiler-plugin</artifactId>
24 |                 <version>3.5.1</version>
25 |                 <configuration>
26 |                     <source>1.8</source>
27 |                     <target>1.8</target>
28 |                 </configuration>
29 |             </plugin>
30 |             <plugin>
31 |                 <groupId>org.apache.maven.plugins</groupId>
32 |                 <artifactId>maven-shade-plugin</artifactId>
33 |                 <version>2.3</version>
34 |                 <executions>
35 |                     <execution>
36 |                         <phase>package</phase>
37 |                         <goals>
38 |                             <goal>shade</goal>
39 |                         </goals>
40 |                         <configuration>
41 |                             <createDependencyReducedPom>false</createDependencyReducedPom>
42 |                             <transformers>
43 |                                 <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
44 |                                     <mainClass>com.github.cstroe.loopapp.Main</mainClass>
45 |                                 </transformer>
46 |                             </transformers>
47 |                         </configuration>
48 |                     </execution>
49 |                 </executions>
50 |             </plugin>
51 |         </plugins>
52 |     </build>
53 | 
54 |     <dependencies>
55 |         <!-- Using Log4j2 instead of SLF4J -->
56 |         <dependency>
57 |             <groupId>org.apache.logging.log4j</groupId>
58 |             <artifactId>log4j-api</artifactId>
59 |             <version>2.17.1</version>
60 |         </dependency>
61 |         <dependency>
62 |             <groupId>org.apache.logging.log4j</groupId>
63 |             <artifactId>log4j-core</artifactId>
64 |             <version>2.17.1</version>
65 |         </dependency>
66 | 	</dependencies>
67 | </project>
68 | 


--------------------------------------------------------------------------------
/src/main/java/com/github/cstroe/loopapp/Main.java:
--------------------------------------------------------------------------------
 1 | package com.github.cstroe.loopapp;
 2 | 
 3 | import org.apache.logging.log4j.LogManager;
 4 | import org.apache.logging.log4j.Logger;
 5 | 
 6 | public class Main {
 7 |     private static final Logger log = LogManager.getLogger(Main.class);
 8 | 
 9 |     public static void main(String[] args) throws InterruptedException {
10 |         int counter = 0;
11 |         while(true) {
12 |             if(counter % 10 == 0) {
13 |                 log.info("Waiting ... {}", counter);
14 |             }
15 |             counter++;
16 |             Thread.sleep(500);
17 |         }
18 |     }
19 | }
20 | 


--------------------------------------------------------------------------------
/src/main/resources/log4j2.xml:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="UTF-8"?>
 2 | 
 3 | <!-- Simple configuration for Log4j2 to output to standard out -->
 4 | <Configuration status="info">
 5 |     <Appenders>
 6 |         <Console name="STDOUT" target="SYSTEM_OUT">
 7 |             <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
 8 |         </Console>
 9 |     </Appenders>
10 | 
11 |     <Loggers>
12 |         <Root level="info">
13 |             <AppenderRef ref="STDOUT"/>
14 |         </Root>
15 |     </Loggers>
16 | </Configuration>


--------------------------------------------------------------------------------