matrix_multiply_java

Matrix Multiply Java Example

This example demonstrates the use of Java eRPC. It could be used with as a server or client. This example is compatible with the Python and C versions of this example.

When the client is started, it generates two random matrices and sends them to the server. The server then performs matrix multiplication and sends the resulting matrix back to the client. The client then prints out the resulting matrix.

eRPC documentation

• eRPC is open-source project stored on github: https://github.com/EmbeddedRPC/erpc
• eRPC documentation can be also found on github: https://github.com/EmbeddedRPC/erpc/wiki

Prerequisites

• Java 21 SDK
• Maven 3.9.5

To check that all the prerequisites are correctly installed, run mvn -v. You should get something like this:

Apache Maven 3.9.5 (***)
Maven home: c:\Program Files\maven\apache-maven-3.9.5
Java version: 21, vendor: Oracle Corporation, runtime: c:\Program Files\Java\jdk-21
Default locale: en_US, platform encoding: UTF-8
OS name: "***", version: "***", arch: "***", family: "***"

• If mvn -v fails, check that you have added maven to the PATH variable.
• If you do not see the correct Java version, check that you have set the JAVA_HOME and PATH variables correctly.

Example's files

• Main.java: Main file
• MatrixMultiplyService.java: Custom service for MatrixMultiplyService interface
• pom.xml: Maven configuration file, with Java eRPC dependency
• resource/erpc_matrix_multiply.erpc: eRPC IDL file for example
• erpc_matrix_multiply/: eRPC output shim code generated from IDL file

eRPC installation

1. Run mvn -f ..\..\erpc_java\pom.xml install. This command install the Java eRPC to the local repository.

Building the example

To build and run this example, we create executable jar with copied dependencies using Maven.

1. Run mvn package to download all dependencies and create executable jar in target/ (all Maven configuration is stored in pom.xml).

Running the example

Parameters

• -c,--client Run client
• -s,--server Run server
• -S,--serial <arg> Serial device (default value is None)
• -B,--baud <arg> Baud (default value is 115200)
• -t,--host <arg> Host IP address (default value is localhost)
• -p,--port <arg> Port (default value is 40)

Running

To execute the example use java with parameter -jar and the jar file we created. The pass the arguments to example.

java -jar .\target\matrix_multiply_java-1.0.jar -s # Server on port 40
java -jar .\target\matrix_multiply_java-1.0.jar -s -p 12345 # Server on port 12345
java -jar .\target\matrix_multiply_java-1.0.jar -c # Client connected to `localhost:40`
java -jar .\target\matrix_multiply_java-1.0.jar -c -S COM6 # Client connected serial port COM6

You can also try this example with a Python or C implementation. For Python server, execute:

python ..\matrix_multiply_tcp_python\matrix_multiply.py --server --host localhost --port 40

and then:

java -jar .\target\matrix_multiply_java-1.0.jar -c