---
title: "Java"
url: https://docs.catalyst.zoho.com/en/tools/tunneling/implementation/ide-config/java/
description: "Catalyst Tunneling allows you to debug Non-HTTPS and Integration functions by routing function calls to your local system using a rever-proxy provider's tunneling URL."
last_updated: 2026-08-17T12:16:04Z
service: All Services
type: general
---

# Configure IDE to Debug Java Functions

For the purposes of this help documentation we are going to illustrate how to configure debugging preferences of Java non-HTTPS and Integration functions in Visual Studio Code, IntelliJ IDEA, and Eclipse IDEs.

> **Note:** This step is only applicable if you wish to **debug your tunneled functions** and if you have used the following CLI command:

```sh
catalyst functions:shell --tunnel tunnel-port-number --debug port-number
```

If you wish only to tunnel your functions and you have used the following CLI command then no IDE configurations is required.

```sh
catalyst functions:shell --tunnel tunnel-port-number
```

This command will **only tunnel your functions** and publish the logs of the functions in the Catalyst CLI.

**Visual Studio Code**

### Configure Visual Studio Code IDE's Debugger

1. Ensure you have all the functions you need to debug in the local machine, and open the concerned project in VS Code.
![catalyst_tunneling_debug_vscode_java_openprojec](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debug_vscode_java_openprojec.webp)

2. Click the **Run/Debug** button present in the menu-bar and create a `launch.json` file, by clicking the "**create a launch.json file**" option.
![catalyst_tunneling_vscode_debug_create_json_high](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_vscode_debug_create_json_high.webp)

This is how the launch.json file appears before you begin configurations.
![catalyst_tunneling_vscode_debug_create_json_high](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_vscode_debug_create_json_high.webp)

3. Copy the JSON snippet below and paste it as value in the "**configurations**" JSON key.

**launch.json**

```json
"configurations": [{
            "type": "java",
            "name": "java_cron", // name can be any name but having the same function name will be helpful while debugging
            "request": "attach",
            "hostName": "localhost",
            "port": 9001,// The debug port number which you specified in the catalyst functions:shell --tunnel 8001 --debug 9001. The port number can be any number which is not being used by any other processes
            "projectName": "java_cron"// The function name
}],

```

4. Save this file and apply the breakpoints in your required lines of code and proceed to the [next step](https://docs.catalyst.zoho.com/en/tools/tunneling/implementation/debug-tunneled-func/java/).
![catalyst_tunneling_debug_vscode_java_brkpts_set](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debug_vscode_java_brkpts_set.webp)

**IntelliJ IDEA**

### Configure IntelliJ IDEA IDE's Debugger

1. Import your project directory in IntelliJ IDE, and configure the run time JDK to match your Java version.
![catalyst_tunneling_intellij_debugger_java_start](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_intellij_debugger_java_start.webp)

> **Note:** You can find out how to configure your JDK in IntelliJ IDEA by visiting their [official help documentation](https://www.jetbrains.com/help/idea/sdk.html).

2. Click **Run>Edit Configurations**.
![catalyst_tunneling_intellij_debugger_java_run_selection](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_intellij_debugger_java_run_selection.webp)

3. Click the **+ icon**, select **Remote JVM Debug** option from the pop-up, and click **OK**.
![catalyst_tunneling_intellij_debugger_java_remote_javm_debugger](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_intellij_debugger_java_remote_javm_debugger.webp)

4. Ensure you set the following values in the pop-up:
    - Name: Set it as your project name or any other name of your preference.
    - In the *Configurations* tab:
        - Debugger mode: **Attach to remote JVM**
        - Host: **localhost**
        - Port: Set the same port value you set for debugging in the Catalyst CLI.
        - Use module classpath: Select the path of your project directory.
        - Click **OK**.
    ![catalyst_tunneling_intellij_debugger_java_configurations](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_intellij_debugger_java_configurations.webp)

5. Set the required debugging points in your code, and proceed to the [next step](https://docs.catalyst.zoho.com/en/tools/tunneling/implementation/debug-tunneled-func/java/).
![catalyst_tunneling_intellij_debugger_java_finally_debug](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_intellij_debugger_java_finally_debug.webp)

**Eclipse**

### Configure Eclipse IDE's Debugger

1. Import your project directory in *Eclipse IDE*.
![catalyst_tunneling_debugging_java_eclipse_import_proj](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_import_proj.webp)

2. Ensure your Java stack and JDK are in the same version by right-clicking your project list and selecting **Build Path > Configure Build Path**.
![catalyst_tunneling_java_debug_eclipse_configure_build_path](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_java_debug_eclipse_configure_build_path.webp)

3. Select **Project Natures**. Search for "**Java**", select "**java**" from the list and click **OK**.
![catalyst_tunneling_debugging_java_eclipse_project_nature](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_project_nature.webp)

4. Ensure **Java Compiler** is selected, and click **Apply and Close** to add the Java compiler for your project.
![catalyst_tunneling_debugging_java_eclipse_select_java_compiler](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_select_java_compiler.webp)

5. Next, right-click your project directory and click **Debug As > Debug Configuration**.
![catalyst_tunneling_debugging_java_eclipse_debug_configurations](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_debug_configurations.webp)

6. Search for *Remote Java Applications*, right-click on the search result and select **New Configurations**.
![catalyst_tunneling_debugging_java_eclipse_select_java_new_configuratons](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_select_java_new_configuratons.webp)

You will be directed to a **Debug Configurations** pop-up.

7. Ensure you have configured the debugger with the following values:
- *Connect* tab:
    - Select your project directory
    - Set Connection Type as "**Standard (Socket Attach)**"
    - Set *Connection Properties* as:
        - Host: **localhost**
        - Port: Enter the port number you set for debugging in the Catalyst CLI
        ![catalyst_tunneling_debugging_java_eclipse_connect_tab](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_connect_tab.webp)

- *Source* tab:
    - Click the **Add** button and select the function directory
    ![catalyst_tunneling_debugging_java_eclipse_source_tab](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_source_tab.webp)

Once you have applied the required configurations, click **Debug**.

8. Open your function file and set your required debug points in your code, and proceed to the [next step](https://docs.catalyst.zoho.com/en/tools/tunneling/implementation/debug-tunneled-func/java/).
![catalyst_tunneling_debugging_java_eclipse_final_debug](https://catalyst-docs-development.zohostratus.in/images/catalyst-extension/tunneling/catalyst_tunneling_debugging_java_eclipse_final_debug.webp)