guides/tutorial.md

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This tutorial will show users how to run the WordCount example locally with Wayang.

# Clone repository
```shell
git clone https://github.com/apache/incubator-wayang.git 
```

# Create binaries
Running following commands to build Wayang and generate the tar.gz  
```shell
cd incubator-wayang
./mvnw clean package -pl :wayang-assembly -Pdistribution 
```
Then you can find the `wayang-assembly-1.0.1-SNAPSHOT-dist.tar.gz` under `wayang-assembly/target` directory.


# Prepare the environment
## Wayang
```shell
tar -xvf wayang-assembly-1.0.1-SNAPSHOT-dist.tar.gz
cd wayang-1.0.1-SNAPSHOT
```

In linux
```shell 
echo "export WAYANG_HOME=$(pwd)" >> ~/.bashrc
echo "export PATH=${PATH}:${WAYANG_HOME}/bin" >> ~/.bashrc
source ~/.bashrc
```
In MacOS
```shell 
echo "export WAYANG_HOME=$(pwd)" >> ~/.zshrc
echo "export PATH=${PATH}:${WAYANG_HOME}/bin" >> ~/.zshrc
source ~/.zshrc
```
## Others
- You need to install Apache Spark version 3 or higher. Don’t forget to set the `SPARK_HOME` environment variable.
- You need to install Apache Hadoop version 3 or higher. Don’t forget to set the `HADOOP_HOME` environment variable.

# Run the program

To execute the WordCount example with Apache Wayang, you need to execute your program with the 'wayang-submit' command:

```shell
cd wayang-1.0.1-SNAPSHOT
./bin/wayang-submit org.apache.wayang.apps.wordcount.Main java file://$(pwd)/README.md
```
##  If you're using Java 17, add the following JVM flags:
Update your `wayang-submit` (wayang-assembly/target/wayang-1.0.1-SNAPSHOT/bin/wayang-submit) script (or command) with:

```shell 
eval "$RUNNER \
  --add-exports=java.base/sun.nio.ch=ALL-UNNAMED \
  --add-opens=java.base/java.nio=ALL-UNNAMED \
  --add-opens=java.base/java.lang=ALL-UNNAMED \
  --add-opens=java.base/java.util=ALL-UNNAMED \
  --add-opens=java.base/java.io=ALL-UNNAMED \
  --add-opens=java.base/java.lang.reflect=ALL-UNNAMED \
  --add-opens=java.base/java.util.concurrent=ALL-UNNAMED \
  --add-opens=java.base/java.net=ALL-UNNAMED \
  --add-opens=java.base/java.lang.invoke=ALL-UNNAMED \
  $FLAGS -cp \"${WAYANG_CLASSPATH}\" $CLASS ${ARGS}"
```

Then you should be able to see outputs like this:

![img.png](../images/wordcount_result.png)