I'm very new in the debugging the code cloned from the Github. However, till now, I have done below :
cloned the repo to my local machine (git clone ) as well as using "sourcetree" software.
built the code (mvn clean install)
able to import the maven project in IDE (Ecliplse, InteliiJ)
After the build completed I'm able to start the application (eg: start.sh) in the target/bin directory which has been created after the build
Logged into the application's UI succesfully
Questions:
- Now, at this moment I am not sure what is the main class file for aplication and from where and which .java file I shall attach the breakpoint
- Once attached the breakpoint how shall I debug it while traversing through the UI.
Can someone please give me a pointer. Thanks in advance!
Eg: I'm testing all this on "Apache/NiFi-Registry" project.
ref: https://github.com/apache/nifi-registry
You're going to need to edit this line in the nifi-registry.sh script to enable remote debugging
run_nifi_registry_cmd="'${JAVA}' -cp '${BOOTSTRAP_CLASSPATH}' -Xms12m -Xmx24m ${BOOTSTRAP_DIR_PARAMS} org.apache.nifi.registry.bootstrap.RunNiFiRegistry $#"
Is it just me, or is that memory footprint really small?
For example, in Kafka, there is this section of the startup script
# Set Debug options if enabled
if [ "x$KAFKA_DEBUG" != "x" ]; then
# Use default ports
DEFAULT_JAVA_DEBUG_PORT="5005"
if [ -z "$JAVA_DEBUG_PORT" ]; then
JAVA_DEBUG_PORT="$DEFAULT_JAVA_DEBUG_PORT"
fi
# Use the defaults if JAVA_DEBUG_OPTS was not set
DEFAULT_JAVA_DEBUG_OPTS="-agentlib:jdwp=transport=dt_socket,server=y,suspend=${DEBUG_SUSPEND_FLAG:-n},address=$JAVA_DEBUG_PORT"
if [ -z "$JAVA_DEBUG_OPTS" ]; then
JAVA_DEBUG_OPTS="$DEFAULT_JAVA_DEBUG_OPTS"
fi
echo "Enabling Java debug options: $JAVA_DEBUG_OPTS"
KAFKA_OPTS="$JAVA_DEBUG_OPTS $KAFKA_OPTS"
fi
Then it runs eventually ${JAVA} ... ${KAFKA_OPTS}, and if you stop Kafka server and start it with
export KAFKA_DEBUG=y; kafka-server-start ...
Then you can attach a remote debugger on port 5005 by default
I understand you're using NiFi Registry, not Kafka, but basically, you need to add arguments to the JVM and reboot it. You can't just attach to the running Registry and walk through the source code.
Remote debugging a Java application
Related
I've got a Spring Boot application that'd I'd like to automatically generate traces for using the OpenTelemetry Java agent, and subsequently upload those traces to Google Cloud Trace.
I've added the following code to the entry point of my application for sending traces:
OpenTelemetrySdk.builder()
.setTracerProvider(
SdkTracerProvider.builder()
.addSpanProcessor(
SimpleSpanProcessor.create(TraceExporter.createWithDefaultConfiguration())
)
.build()
)
.buildAndRegisterGlobal();
...and I'm running my application with the following system properties:
-javaagent:path/to/opentelemetry-javaagent-all.jar \
-jar myapp.jar
...but I don't know how to connect the two.
Is there some agent configuration I can apply? Something like:
-Dotel.traces.exporter=google_cloud_trace
I ended up resolving this as follows:
Clone the GoogleCloudPlatform /
opentelemetry-operations-java repo
git clone
git#github.com:GoogleCloudPlatform/opentelemetry-operations-java.git
Build the exporter-auto project
./gradlew clean :exporter-auto:shadowJar
Copy the jar produced in exporter-auto/build/libs to my target project
Run the application with the following arguments:
-javaagent:path/to/opentelemetry-javaagent-all.jar
-Dotel.javaagent.experimental.extensions=[artifact-from-step-3].jar
-Dotel.traces.exporter=google_cloud_trace
-Dotel.metrics.exporter=none
-jar myapp.jar
Note: This setup does not require any explicit code changes in the target code base.
I have a basic java app using java.awt Swing UI and I want to create a snap for it so when it's installed there is a launcher available and my UI Launches. I use gradle and the jar task to create a jar which works fine.
Naturally I have in a class that when called loads my app just fine:
package com.foo
class Bar() {
static void main(String... args) { launchUI() }
}
I created a snap folder at the root of the project and a snap.yaml where i followed the instructions on https://snapcraft.io/docs/java-applications so i have a snap yaml that produces a snap file which also installs fine:
name: deepthought
base: core18
version: '0.0.7'
summary: ""
icon: gui/foo.png
description: |
Computes the ultimate answer for life the universe and everything
grade: devel # must be 'stable' to release into candidate/stable channels
confinement: devmode # use 'strict' once you have the right plugs and slots
# This doesn't work
#apps:
# htmldoc:
# command: desktop-launch $SNAP/bin/foo.sh
## desktop: share/applications/htmldoc.desktop
# plugs: [home, network, x11]
parts:
foopart:
plugin: gradle
source: https://github.com/bsautner/foo.git
source-type: git
gradle-options: [] # suppress running of tests and run the war task
gradle-output-dir: build/libs
I've spent quite some time trying to figure out:
If i create a shell script to run a java -jar foo.jar command it ends up in the /snap directory but it's not on the users path so they can't get to it
I've tried creating launchers but always get an error that my launcher can't be found, if i put it in my root folder as /bin/launch.sh snap can't find it and if i put it in the snap/bin/ folder i also get errors to not put things in the snap folder
When I do install my snap, i don't see where it puts my jar i want to execute, so i can't write a script that does that
I'd really appreciate if anyone can share a working snap.yaml for a java program with a launcher and if there is any mention of a path to something that you note where those files are in relation to the path of the /snap/snap.yaml file
ok figured it out - the docs don't say this but the files are relative to the root of the project so even though the yaml says this is the launch
apps:
cmd3:
command: usr/bin/foo.sh
foo.sh should be in the root of the project and the orginize section here moves it to the bin dir
foo:
plugin: gradle
source-type: local
source: .
build-packages:
- openjdk-11-jdk
stage-packages:
- openjdk-11-jdk
- x11-utils
organize:
${SNAPCRAFT_PART_BUILD}/jg-snap: usr/bin/foo.sh
The jar is in the /snap/foo/current/usr/jar directory
I try to get a Newrelic java agent to run in a docker container to monitor a HiveMetaStore server running in the docker container.
In order to get the Newrelic agent started during the startup of the JVM I have to pass-javaagent /path/to/newrelic.jar flag to the JVM.
I tried:
hive --service metastore -javaagent /path/to/newrelic.jar
This failed with "Unrecognized Option" in the HiveMetaStore server code, where it should not have ended up at all.
The hive script invokes the bin/ext/metastore.sh script which in turn invokes
exec $HADOOP jar $JAR $CLASS "$#"
So I tried to patch this invocation:
exec $HADOOP -javaagent /path/to/newrelic.jar jar $JAR $CLASS "$#"
This failed as well.
Then I took a deeper look at the hadoop script. Finally function hadoop_java_exec in libexec//hadoop_functions.sh invokes:
exec "${JAVA}" "-Dproc_${command}" ${HADOOP_OPTS} "${class}" "$#"
So I patched this code:
exec "${JAVA}" "-javaagent /path/to/newrelic.jar" "-Dproc_${command}" ${HADOOP_OPTS} "${class}" "$#"
This again failed.
Last but not least I recognized that one can pass java properties via HADOOP _OPTS (in libexec/hadoop_functions.sh):
function hadoop_finalize_hadoop_opts
{
hadoop_translate_cygwin_path HADOOP_LOG_DIR
hadoop_add_param HADOOP_OPTS hadoop.log.dir "-Dhadoop.log.dir=${HADOOP_LOG_DIR}"
hadoop_add_param HADOOP_OPTS hadoop.log.file "-Dhadoop.log.file=${HADOOP_LOGFILE}"
…
}
But I could not figure out how to pass -javaagent:/path/to/newrelic.jar using this mechanism.
Is anyone out there who has tried this before and can help with that ?
My apology if this is a stupid question. Thanks upfront, Ute
function hadoop_finalize_hadoop_opts
{
hadoop_translate_cygwin_path HADOOP_LOG_DIR
hadoop_add_param HADOOP_OPTS hadoop.log.dir "-Dhadoop.log.dir=${HADOOP_LOG_DIR}"
hadoop_add_param HADOOP_OPTS hadoop.log.file "-Dhadoop.log.file=${HADOOP_LOGFILE}"
…
hadoop_add _param HADOOP_OPTS java.javaagent -javaagent:${NEWRELIC_AGENT_HOME}\/newrelic.jar
}
Adding the last statement to got the agent started. I see in the container:
/usr/lib/jvm/default-jvm/bin/java -Dproc_jar -Dproc_metastore , … , NullAppender - javaagent:/opt/newrelic-agent-5.10.0/newrelic.jar org.apache.hadoop.util.RunJar /opt/apache-hive-3.1.2-bin/lib/hive-metastore-3.1.2.jar org.apache.hadoop.hive.metastore.HiveMetaStore
I don't understand the "NullAppender" yet but at least the agent seems to be running now.
I'm using Intellij with WebSphere 8. When I run from within IDE the server works normally. When I try to run it in debug mode however, it fails with the following error:
C:\IBM\WebSphere\AppServer\profiles\AppSrv01\bin\generated_websphere_server_start_script.cmd
C:\IBM\WebSphere\AppServer\java\bin\java -Dfile.encoding=windows-1252 -classpath "C:\IBM\WebSphere\AppServer\runtimes\com.ibm.ws.admin.client_8.5.0.jar;C:\IBM\WebSphere\AppServer\plugins\com.ibm.ws.security.crypto.jar;C:\Program Files (x86)\JetBrains\IntelliJ IDEA 13.1.3\plugins\webSphereIntegration\lib\webSphereIntegration.jar;C:\Program Files (x86)\JetBrains\IntelliJ IDEA 13.1.3\plugins\JavaEE\lib\javaee-impl.jar;C:\Program Files (x86)\JetBrains\IntelliJ IDEA 13.1.3\lib\openapi.jar;C:\Program Files (x86)\JetBrains\IntelliJ IDEA 13.1.3\plugins\webSphereIntegration\lib\specifics\webSphereClientImpl.jar" com.intellij.javaee.oss.process.JavaeeProcess 62847 com.intellij.j2ee.webSphere.agent.WebSphereAgent
Error: JDWP agent already loaded - please check java command line options
[2014-08-11 01:58:59,248] Artifact x.ear: Server is not connected. Deploy is not available.
JVMJ9TI064E Agent initialization function Agent_OnLoad failed for library jdwp, return code -1
Detected server admin port: 8880
JVMJ9VM015W Initialization error for library j9jvmti26(-3): JVMJ9VM009E J9VMDllMain failed
Detected server http port: 9080
Disconnected from server
I tried almost everything I have no idea what the problem is. I did google it for several hours with no luck.
Do anyone know what this all is about and how can it be fixed?
Here is my server configuration:
Solution 1
unchecked the Pass environment variables check box and restart the server in debug mode. it should work properly.
Run --> Edit Configuration --> websphere server --> Startup/Conections tab
select debug, you will see the Pass environment variables check box. it need to be unchecked for debug to work.
Solution 2
if debug mode of websphere is working in eclipse and not working in intellij that reason i found out is debugging serverice on the websphere is already started and intellij is again trying to start the debggin service. so stop the service from websphere console (Servers > Server Types > WebSphere application servers > [serverName] > Debugging Service) and all the default configurations in intellij should work.
I had the same problem. Finally I figure it out. I hope this solution helps. I'm using Intellij idea 2019.1.3.. and WebSphere 8.5.5.13
check WebSphere start server script find debug env variable name (in my script (WebSphere\AppServer\bin\startServer.bat)
WAS_DEBUG)
add same debug option name to intelliJ IDEA
run- debug configuration environment tab.
Since default env variable is debug and cannot be overridden
check pass env variables
add WAS_DEBUG option as I did
or you can update WAS_DEBUG as DEBUG (same as default in IntelliJ) in server startup.bat script.
Both should work.
Pretty old, but i was able to experience too!
They will try to fix this now in: https://youtrack.jetbrains.com/issue/IDEA-193580
firstly, sorry if the translation is not good, I am Brazilian and I would like to share the solution I made.
First: Locate the file "startServer.bat in "WebSphere\AppServer\bin" and open it with any text editor.
Second: Search for the second incidence of the word "WAS_DEBUG" and replace it with "DEBUG", as shown in the image...
Third: In Intellij, go to the server settings and in the "Startup/Connection" tab, select debug.
Fourth: Now uncheck the "use default" checkbox in "Startup script" and point to the location of the "startServer.bat" file in the webSphere directory.
Fifth: Right on the left side of the checkbox, there is an option to enter a parameter. Click and a "Program Arguments" field will appear. Enter the server name, in my case it was "server1".
Okay, now just test
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I am trying to create a windows service for Apache tomcat 7.0.45.
( in windows version 7)
I executed this :
C:/tomcat7/bin> service install Mytomcat7
Windows service has been created. but it wont start and throws "specific server error code 4".
Can you please help with the steps to create windows service.
I had the same problem!
Found out, that the service.bat didn't configure the service the right way. If you enable the logging from your service starter:
Then you'll see in your loggs something like:
[2014-02-19 16:40:35] [error] ( javajni.c:863 ) [ 2636] FindClass org/apache/catalina/startup/Bootstrap failed
[2014-02-19 16:40:35] [debug] ( javajni.c:964 ) [ 2636] Java Worker thread finished org/apache/catalina/startup/Bootstrap:main with status=3
[2014-02-19 16:40:35] [error] ( prunsrv.c:1183) [ 5000] Failed to start Java
[2014-02-19 16:40:35] [error] ( prunsrv.c:1536) [ 5000] ServiceStart returned 4
You'll notice that there is some classpath problem with the starter. In fact that's the problem! Your service.bat didn't configure the service the right way:
Note: You can also choose "Use default" above "Java Virtual Machine" to use whatever JVM is defined in JAVA_HOME
You'll need to set the classpath correctly:
c:\webclient\apache-tomcat\bin\tomcat-juli.jar;c:\webclient\apache-tomcat\bin\tomcat-juli.jar;c:\webclient\apache-tomcat\bin\bootstrap.jar
In my case i "installed" tomcat at: c:\webclient\apache-tomcat replace that part with yours. In my case not even the Java VM was set.. I'm not shure whether this is a problem with the current versions of tomcat (and it's service.bat), or with some sort of permission problem on the windows server itself..
To solve this error perform the following steps:
Run the tomcat7w.exe monitor application found in <TOMCAT_HOME>/bin.Tomcat7w is a GUI application for monitoring and configuring Tomcat services. If you named your service Mytomcat7 you will need to rename this file to Mytomcat7.exe before running it
In the "Startup" tab change the value of "Mode" from jvm to Java
Do the same in the "Shutdown" tab
The easiest way to setup a tomcat Windows service is to use the Tomcat Windows Service Installer found on the same page as tomcat downloads.
http://tomcat.apache.org/download-70.cgi
However, if you are unable to use this installer. Then you can as you have try the above. The service created 'Mytomcat7' can be managed by the tomcat7w.exe file, after you rename it to 'Mytomcat7w.exe'.
Run the renamed file and you will be able to see all options for the service. The error you are seeing is likely related to an invalid JVM location or JVM mode not set to auto.
Details of settings found here:
http://tomcat.apache.org/tomcat-7.0-doc/windows-service-howto.html
I would just use the installer, it will make your life easier.
http://mirror.ox.ac.uk/sites/rsync.apache.org/tomcat/tomcat-7/v7.0.50/bin/apache-tomcat-7.0.50.exe