Building and Running

Overview

This guide covers how to build the MySQL SQL Editor application from source, run it during development, and package it as a distributable JAR file.

Prerequisites

Before building, ensure you have:

Completed the development environment setup
JDK 8 or later installed and configured
MySQL Connector/J JAR in the lib/ directory

Compilation

Using the Command Line

Compile all Java source files from the project root directory:

# Create output directory for compiled classes
mkdir -p bin

# Compile all Java files with MySQL JDBC driver in classpath
javac -cp "lib/mysql-connector-j-9.2.0.jar" -d bin \
  src/com/app/Main.java \
  src/com/app/Model/Model.java \
  src/com/app/View/View.java \
  src/com/app/View/SqlEditorView.java \
  src/com/app/Controller/Controller.java

The -d bin flag outputs compiled .class files to the bin/ directory, keeping them separate from source files.

Compilation Flags Explained:

-cp "lib/mysql-connector-j-9.2.0.jar" - Adds the MySQL JDBC driver to the classpath
-d bin - Specifies the output directory for compiled class files
Source files are listed explicitly to ensure proper compilation order

On Windows, use semicolons (;) as the classpath separator if you need to include multiple JARs:

javac -cp "lib/mysql-connector-j-9.2.0.jar;other.jar" -d bin ...

On Linux/macOS, use colons (:).

Using an IDE

IntelliJ IDEA
Eclipse
VS Code

Automatic Compilation:IntelliJ IDEA compiles your code automatically as you edit:

Ensure the MySQL JDBC driver is added to the project libraries (see Setup)
Edit any Java file - IntelliJ will compile it automatically
Check for errors in the Problems tool window

Manual Build:To manually trigger a build:

Go to Build → Build Project (Ctrl+F9 / Cmd+F9)
Or click the hammer icon in the toolbar
Compiled classes are placed in the out/ directory by default

Running the Application

From Command Line

After compilation, run the application using the java command:

# Run from the project root
java -cp "bin:lib/mysql-connector-j-9.2.0.jar" com.app.Main

The classpath must include both:

bin/ - Your compiled application classes
lib/mysql-connector-j-9.2.0.jar - The MySQL JDBC driver

What happens when you run:

The JVM loads com.app.Main class
The main method executes (see src/com/app/Main.java:22)
The application initializes the MVC components:
- Creates Model instance for database operations
- Creates View instance (login window)
- Creates SqlEditorView instance (SQL editor window, initially hidden)
- Creates Controller to wire everything together
The login window appears, ready for database connection

From IDE

IntelliJ IDEA
Eclipse
VS Code

Open src/com/app/Main.java
Right-click anywhere in the file
Select Run ‘Main.main()’
Or click the green play button in the gutter next to the main method

Create a Run Configuration:For repeated runs with custom settings:

Go to Run → Edit Configurations…
Click + → Application
Set:
- Name: MySQL SQL Editor
- Main class: com.app.Main
- VM options: (optional) -Xmx512m for memory settings
Click OK
Use the run configuration dropdown to launch the app

Open src/com/app/Main.java
Right-click in the editor
Select Run As → Java Application
Or click the green run button in the toolbar

Create a Run Configuration:

Go to Run → Run Configurations…
Right-click Java Application → New Configuration
Set:
- Name: MySQL SQL Editor
- Project: Your project name
- Main class: com.app.Main
Click Apply and Run

Open src/com/app/Main.java
Click Run above the main method
Or press F5 to start debugging

Using launch.json:Create .vscode/launch.json for custom configurations:

{
  "version": "0.2.0",
  "configurations": [
    {
      "type": "java",
      "name": "MySQL SQL Editor",
      "request": "launch",
      "mainClass": "com.app.Main",
      "projectName": "mysql-sql-editor",
      "classPaths": [
        "${workspaceFolder}/bin",
        "${workspaceFolder}/lib/mysql-connector-j-9.2.0.jar"
      ]
    }
  ]
}

Packaging as JAR

Creating an Executable JAR

Package the application as a standalone JAR file that can be distributed and run anywhere:

Compile the Application

First, ensure all classes are compiled (see Compilation above).

Create Manifest File

Create a manifest file that specifies the entry point and classpath:

# Create MANIFEST.MF
cat > MANIFEST.MF << EOF
Manifest-Version: 1.0
Main-Class: com.app.Main
Class-Path: mysql-connector-j-9.2.0.jar
EOF

The Class-Path entry tells the JVM where to find the MySQL JDBC driver relative to the JAR file.

Package with jar Command

Create the JAR file including all compiled classes:

# Create JAR with manifest
jar cfm mysql-sql-editor.jar MANIFEST.MF -C bin .

This creates mysql-sql-editor.jar containing all compiled classes from the bin/ directory.

Run the JAR

Run the packaged application:

# Ensure mysql-connector-j-9.2.0.jar is in the same directory
java -jar mysql-sql-editor.jar

The MySQL JDBC driver JAR (mysql-connector-j-9.2.0.jar) must be in the same directory as your application JAR, or you must specify its location with -cp.

Creating a Fat JAR (JAR with Dependencies)

For easier distribution, create a “fat JAR” that includes all dependencies:

# Extract MySQL JDBC driver classes
mkdir -p temp
cd temp
jar xf ../lib/mysql-connector-j-9.2.0.jar
cd ..

# Copy compiled classes
cp -r bin/* temp/

# Create fat JAR
jar cfe mysql-sql-editor-fat.jar com.app.Main -C temp .

# Clean up
rm -rf temp

The fat JAR can be run with a simple java -jar mysql-sql-editor-fat.jar command without needing external dependencies.

Build Automation

For repeated builds, consider creating a build script:

#!/bin/bash
set -e

echo "Cleaning previous build..."
rm -rf bin
mkdir -p bin

echo "Compiling Java sources..."
javac -cp "lib/mysql-connector-j-9.2.0.jar" -d bin \
  src/com/app/Main.java \
  src/com/app/Model/Model.java \
  src/com/app/View/View.java \
  src/com/app/View/SqlEditorView.java \
  src/com/app/Controller/Controller.java

echo "Build successful!"
echo "Run with: java -cp \"bin:lib/mysql-connector-j-9.2.0.jar\" com.app.Main"

Make the script executable and run it:

# Linux/macOS
chmod +x build.sh
./build.sh

# Windows
build.bat

Troubleshooting

NoClassDefFoundError: com/mysql/cj/jdbc/Driver The MySQL JDBC driver is not in the classpath. Ensure:

The JAR is in the lib/ directory
Your classpath includes lib/mysql-connector-j-9.2.0.jar

Error: Could not find or load main class com.app.Main Check that:

The bin/ directory is in your classpath
The package structure is correct: bin/com/app/Main.class
You’re using the fully qualified class name: com.app.Main

Compilation errors about missing symbols

Ensure all source files are compiled together
Check that the MySQL JDBC driver is in the compilation classpath
Verify you’re using JDK 8 or later

Next Steps

Learn about project dependencies
Explore the architecture components for detailed class documentation
Review the MVC pattern to understand the design

Getting Started

User Guide

Architecture

Development

Reference

Overview

Prerequisites

Compilation

Using the Command Line

Using an IDE

Running the Application

From Command Line

From IDE

Packaging as JAR

Creating an Executable JAR

Creating a Fat JAR (JAR with Dependencies)

Build Automation

Troubleshooting

Next Steps

Build docs developers (and LLMs) love

Getting Started

User Guide

Architecture

Development

Reference

​Overview

​Prerequisites

​Compilation

​Using the Command Line

​Using an IDE

​Running the Application

​From Command Line

​From IDE

​Packaging as JAR

​Creating an Executable JAR

​Creating a Fat JAR (JAR with Dependencies)

​Build Automation

​Troubleshooting

​Next Steps

Build docs developers (and LLMs) love

Overview

Prerequisites

Compilation

Using the Command Line

Using an IDE

Running the Application

From Command Line

From IDE

Packaging as JAR

Creating an Executable JAR

Creating a Fat JAR (JAR with Dependencies)

Build Automation

Troubleshooting

Next Steps