---
{
    "title": "Setting FE dev env - Eclipse",
    "language": "en"
}
---

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# Setting FE dev env using Eclipse

## Preparation

* JDK 1.8+
* Maven 3.x+
* Eclipse，with [M2Eclipse](http://www.eclipse.org/m2e/) installed

### Code Generation

The FE module requires part of the generated code, such as Thrift, Protobuf, Jflex, CUP and other frameworks. 

1. Under Linux, enter the source code directory `fe` and execute the following command:

   ```
    mvn  generate-sources
   ```
    
2. If use windows as development environment, then package the generated `fe/fe-core/target/generated-sources` directory:

   `fe/fe-core/target/ && tar czf java.tar.gz generated-sources/`

3. Copy `java.tar.gz` to the `fe/fe-core/target/` directory of the development environment and unzip

    ```
    cp java.tar.gz /path/to/doris/fe/fe-core/target/
    cd /path/to/doris/fe/fe-core/target/ && tar xzf java.tar.gz
    ```

## Import FE project

1. In the `fe/` directory of the development environment, execute the following command to generate the Eclipse project file:

    `cd /path/to/doris/fe/ && mvn -npr eclipse:eclipse -Dskip.plugin=true`
    
    After the execution is completed, the `.project` and `.classpath` files will be generated in the `fe/` directory.

2. Import FE project

    * Open Eclipse，choose `File -> Import`.
    * Choose `General -> Existing Projects into Workspace`.
    * `Select root directory` and choose `fe/` directory，click `Finish` to finish.
    * Right click the project, and choose `Build Path -> Configure Build Path`.
    * In the `Java Build Path` dialog, choose the `Source` tab, click `Add Folder`, and select the `java/` directory that was copied and unzipped before adding.
    * Click `Apply and Close` to finish.

At this point, FE project import is complete. The project directory in Eclipse is roughly as follows:

![](/images/eclipse-import-fe-project-1.png)

## Run Unit Test

Right-click on the unit test file you want to run and select `Run As -> JUnit Test`. (If you want to debug, select `Debug As -> JUnit Test`).

If the following error occurs:

```
java.lang.Exception: Method xxxx should have no parameters
```

Then right-click the unit test file and select `Run As -> Run Configurations...`. (If you want to debug, select `Debug As -> Debug Configurations...`).

Add to the `VM arguments` in the `Arguments` tab:

```
-javaagent:${settings.localRepository}/org/jmockit/jmockit/1.48/jmockit-1.48.jar
```

Among them, `${settings.localRepository}` should be replaced with the path of the maven library path, such as:

```
-javaagent:/Users/cmy/.m2/repository/org/jmockit/jmockit/1.48/jmockit-1.48.jar
```

Then just run `Run/Debug`.

## Run FE

You can directly start an FE process in Ecplise to facilitate debugging the code.

1. Create a runtime directory

    ```
    mkdir /path/to/doris/fe/run/
    cd /path/to/doris/fe/run/
    mkdir conf/ log/ palo-meta/
    ```
    
2. Create configuration file
    
    Create the configuration file `fe.conf` in the `conf/` directory created in the first step. You can directly copy `conf/fe.conf` in the source directory and make simple changes.
    
3. Find the `src/main/java/org/apache/doris/PaloFe.java` file in Ecplise, right-click and select `Run As -> Run Configurations...`. Add the following environment variables to the `Environment` tab:

    * `DORIS_HOME: /path/to/doris/fe/run/`
    * `PID_DIR: /path/to/doris/fe/run/`
    * `LOG_DIR: /path/to/doris/fe/run/log`

4. Right-click `PaloFe.java` and select `Run As -> Java Application` to start FE.

## Code Update

1. Update lexical and grammar files or proto and thrift files

    If you modified `fe/src/main/cup/sql_parser.cup` or `fe/src/main/jflex/sql_scanner.flex` file or proto and thrift files. You need to execute the following commands in the `fe/` directory:
    
    ```
    mvn  generate-sources
    ```
    
    Then refresh the project in Eclipse.
        
2. Update maven dependencies

    If you update the dependency in `fe/pom.xml`, you need to execute the following command in the `fe/` directory:

    `mvn -npr eclipse:eclipse -Dskip.plugin=true`
    
    Then refresh the project in Eclipse. If it cannot be updated, it is recommended to delete the project and import it again according to this document.

## Imports Order

In order to maintain the Imports order of Java, please perform the following operations to set the Imports Order of the project.

1. Create the file `fe_doris.importorder` and write the following:

    ```
    #Organize Import Order
    #Wed Jul 01 16:42:47 CST 2020
    4=javax
    3=java
    2=org
    1=com
    0=org.apache.doris
    ```

2. Open Eclipse Preferences, select `Java -> Code Style -> Organize Imports`. Click `Import` to import the above file.