Not able to connect to tcp Server

[rdhivya...@gmail.com]

Hi Team,

I am trying to run my JVM in TCP client mode and my TCP server is listening.
Below is the configuration setup.

Server End:(Configured in my eclipse)

-javaagent:jacoco-0.8.4\lib\jacocoagent.jar=port=9005,output=tcpserver,address=*

Client End:(In my cmd)

SET _JAVA_OPTIONS=-javaagent:jacoco-0.8.4\lib\jacocoagent.jar=port=9005,output=tcpclient,address=127.0.0.1

Problem:When ever i try to execute or compile my code it throws the below error in the clien end.

java.net.ConnectException: Connection refused: connect
at java.base/java.net.PlainSocketImpl.connect0(Native Method)
at java.base/java.net.PlainSocketImpl.socketConnect(PlainSocketImpl.java:101)
at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399)
at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242)
at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224)
at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:403)
at java.base/java.net.Socket.connect(Socket.java:591)
at java.base/java.net.Socket.connect(Socket.java:540)
at java.base/java.net.Socket.<init>(Socket.java:436)
at java.base/java.net.Socket.<init>(Socket.java:213)
at org.jacoco.agent.rt.internal_035b120.output.TcpClientOutput.createSocket(TcpClientOutput.java:85)
at org.jacoco.agent.rt.internal_035b120.output.TcpClientOutput.startup(TcpClientOutput.java:49)
at org.jacoco.agent.rt.internal_035b120.Agent.startup(Agent.java:122)
at org.jacoco.agent.rt.internal_035b120.Agent.getInstance(Agent.java:50)
at org.jacoco.agent.rt.internal_035b120.PreMain.premain(PreMain.java:49)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at java.instrument/sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:513)
at java.instrument/sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:525)
java.lang.NullPointerException
at org.jacoco.agent.rt.internal_035b120.output.TcpClientOutput.writeExecutionData(TcpClientOutput.java:72)
at org.jacoco.agent.rt.internal_035b120.Agent.shutdown(Agent.java:137)
at org.jacoco.agent.rt.internal_035b120.Agent$1.run(Agent.java:54)

I am not sure whether I am configuring it properly.
Guide me to move further.
Thanks

-Dhivya

[Marc Hoffmann]

Hi Dhivya,

what exactly do you want to do? Why do you need tcpserver/tcpclient as
output mode?

You can't connect JaCoCo agents to each other.

Regards,
-marc

[rdhivya...@gmail.com]

Hi Marc,

I would like to get the code coverage report without shutting down my application, I thought the agents will be able to connect to each other. But I was wrong.

Regards,
Dhivya.

[Evgeny Mandrikov]

Please have a look at examples in documentation - https://www.jacoco.org/jacoco/trunk/doc/api.html :

• https://www.jacoco.org/jacoco/trunk/doc/examples/java/ExecutionDataClient.java - connects to agent started with "output=tcpserver"
• https://www.jacoco.org/jacoco/trunk/doc/examples/java/ExecutionDataServer.java - waits connection from agent started with "output=tcpclient"
• https://www.jacoco.org/jacoco/trunk/doc/examples/java/MBeanClient.java - uses JMX to connect to agent started with "jmx=true"
  

[Evgeny Mandrikov]

And there is ready-to-use "dump" command in JaCoCo Command Line Interface - https://www.jacoco.org/jacoco/trunk/doc/cli.html

[rdhivya...@gmail.com]

Hi,

Thanks. I tried setting the agent in tcpserver mode and fetch the exec file using the dump CLI command. But when I try to fetch the report using cli, get the below error.

Configuration:
-javaagent:jacoco-0.8.4\lib\jacocoagent.jar"=port=9005,output=tcpserver,address=*

dump command:
java -jar jacoco-0.8.4\lib\jacococli.jar dump --port 9005 --destfile C:\Dhivya\jacoco\jacoco-11july.exec

Report Command:

java -jar jacoco-0.8.4\lib\jacococli.jar report jacoco-client.exec --classfiles MyRest\target\classes\com\infor\m3\MyRest\excel\* --html jacoco\html-tomcat\ --name cc-report

Error:
[INFO] Loading execution data file C:\Users\dravichandran\eclipse-workspace\Jacoco\jacoco-client.exec.
[INFO] Loading execution data file C:\Users\dravichandran\eclipse-workspace\MyRest\target\classes\com\infor\m3\MyRest\excel\RefreshSheet.class.
Exception in thread "main" java.io.IOException: Invalid execution data file.
at org.jacoco.cli.internal.core.data.ExecutionDataReader.read(ExecutionDataReader.java:89)
at org.jacoco.cli.internal.core.tools.ExecFileLoader.load(ExecFileLoader.java:59)
at org.jacoco.cli.internal.core.tools.ExecFileLoader.load(ExecFileLoader.java:73)
at org.jacoco.cli.internal.commands.Report.loadExecutionData(Report.java:98)
at org.jacoco.cli.internal.commands.Report.execute(Report.java:82)
at org.jacoco.cli.internal.Main.execute(Main.java:89)
at org.jacoco.cli.internal.Main.main(Main.java:104).

Regards,
Dhivya

[Evgeny Mandrikov]

On Thursday, July 11, 2019 at 2:06:02 PM UTC+2, rdhivya...@gmail.com wrote:

Hi,

Thanks. I tried setting the agent in tcpserver mode and fetch the exec file using the dump CLI command. But when I try to fetch the report using cli, get the below error.

 

Configuration:
 -javaagent:jacoco-0.8.4\lib\jacocoagent.jar"=port=9005,output=tcpserver,address=*

 

dump command:
java -jar jacoco-0.8.4\lib\jacococli.jar dump  --port 9005 --destfile C:\Dhivya\jacoco\jacoco-11july.exec

This command writes to file "C:\Dhivya\jacoco\jacoco-11july.exec", but next command uses file "jacoco-client.exec" Why?

 

Report Command:

java -jar jacoco-0.8.4\lib\jacococli.jar report jacoco-client.exec --classfiles MyRest\target\classes\com\infor\m3\MyRest\excel\* --html jacoco\html-tomcat\ --name cc-report

This command also has "\*" (backslash character followed by star character) at the end of value for "--classfiles" parameter. Why?

Your directory "MyRest\target\classes\com\infor\m3\MyRest\excel" 

for sure contains file "RefreshSheet.class"

let's say that it also contains file "Foo.class"

I'm pretty sure that in your command line interpreter aka shell this star character causes command to be interpreted as

java -jar jacoco-0.8.4\lib\jacococli.jar report jacoco-client.exec --classfiles MyRest\target\classes\com\infor\m3\MyRest\excel\Foo.class MyRest\target\classes\com\infor\m3\MyRest\excel\RefreshSheet.class --html jacoco\html-tomcat\ --name cc-report

So that 

"jacoco-client.exec" is first value for "execfiles" parameter,

"MyRest\target\classes\com\infor\m3\MyRest\excel\Foo.class" is value for "--classfiles" parameter,

"MyRest\target\classes\com\infor\m3\MyRest\excel\RefreshSheet.class" is second value for "execfiles" parameter,

thus you get loading of two execution data files

Error:
[INFO] Loading execution data file C:\Users\dravichandran\eclipse-workspace\Jacoco\jacoco-client.exec.
[INFO] Loading execution data file C:\Users\dravichandran\eclipse-workspace\MyRest\target\classes\com\infor\m3\MyRest\excel\RefreshSheet.class.

whereas las one is not execution data file and so you get corresponding exception

 

Exception in thread "main" java.io.IOException: Invalid execution data file.
        at org.jacoco.cli.internal.core.data.ExecutionDataReader.read(ExecutionDataReader.java:89)
        at org.jacoco.cli.internal.core.tools.ExecFileLoader.load(ExecFileLoader.java:59)
        at org.jacoco.cli.internal.core.tools.ExecFileLoader.load(ExecFileLoader.java:73)
        at org.jacoco.cli.internal.commands.Report.loadExecutionData(Report.java:98)
        at org.jacoco.cli.internal.commands.Report.execute(Report.java:82)
        at org.jacoco.cli.internal.Main.execute(Main.java:89)
        at org.jacoco.cli.internal.Main.main(Main.java:104).

You don't need to specify "\*", because

value of "--classfiles" parameter can be a directory

and in this case all class files from this directory and all sub-directories will be used.

So you can even use "C:\Users\dravichandran\eclipse-workspace\MyRest\target\classes".

For example given following "Example.java" file in directory "src"

class Example {

    public static void main(String[] args) {

        System.out.println("Hello, World!");

        while (true) ;

    }

}

after compilation into directory "classes"

javac src\Example.java -d classes

execution of

java -javaagent:jacoco-0.8.4\lib\jacocoagent.jar=output=tcpserver -cp classes Example

java -jar jacoco-0.8.4\lib\jacococli.jar dump --destfile jacoco.exec

java -jar jacoco-0.8.4\lib\jacococli.jar report jacoco.exec --classfiles classes --sourcefiles src --html report

produces following report

[rdhivya...@gmail.com]

Thanks, Evgeny for being very supportive. It's working now.
You made my day.

Regards,
Dhivya.

[Dhivya]

Hi,

I want to run the Example.java file in the server and write the execution data to my local system.

So I made the below execution in server and got the "cannot assign requested address: JVM_Bind.".

I am not sure where I am doing wrong. Help me in moving forward.

java -javaagent:jacoco-0.8.4\lib\jacocoagent.jar=output=tcpserver,address=<mylocalsystemaddress>,port=9025 -cp java\classes Example

Error:

java.net.BindException: Cannot assign requested address: JVM_Bind

        at java.net.DualStackPlainSocketImpl.bind0(Native Method)

        at java.net.DualStackPlainSocketImpl.socketBind(Unknown Source)

        at java.net.AbstractPlainSocketImpl.bind(Unknown Source)

        at java.net.PlainSocketImpl.bind(Unknown Source)

        at java.net.ServerSocket.bind(Unknown Source)

        at java.net.ServerSocket.<init>(Unknown Source)

        at org.jacoco.agent.rt.internal_035b120.output.TcpServerOutput.createServerSocket(TcpServerOutput.java:106)

        at org.jacoco.agent.rt.internal_035b120.output.TcpServerOutput.startup(TcpServerOutput.java:53)

        at org.jacoco.agent.rt.internal_035b120.Agent.startup(Agent.java:122)

        at org.jacoco.agent.rt.internal_035b120.Agent.getInstance(Agent.java:50)

        at org.jacoco.agent.rt.internal_035b120.PreMain.premain(PreMain.java:49)

        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

        at java.lang.reflect.Method.invoke(Unknown Source)

        at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(Unknown Source)

        at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(Unknown Source)

Hello, World!

Regards,
Dhivya.

[Evgeny Mandrikov]

Hi,

Have you tried searching the message in internet - https://lmgtfy.com/?q=Cannot+assign+requested+address%3A+JVM_Bind ?

Also javadoc of BindExceptions ( https://docs.oracle.com/javase/7/docs/api/java/net/BindException.html ) is pretty explicit:

Signals that an error occurred while attempting to bind a socket to a local address and port. Typically, the port is in use, or the requested local address could not be assigned.