How to create a BufferedImage from a bunch of smaller BufferedImages.

main.java

package main;

import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;

/**
* Main
* <p>
* A short class for displaying how to write multiple BufferedImages to
* one larger image to create a larger image overall.
*
* I.e. Using "Tile" images to create a "Map".
*/
public class Main
{
	/**
	* Main Method
	*/
	public static void main(String[] args)
	{
		BufferedImage map = null;
		BufferedImage tile1 = null;
		BufferedImage tile2 = null;
		
    		// Load the tile images you want to use when building the map.
		try
		{
			tile1 = ImageIO.read(Main.class.getResourceAsStream("tile1.png"));
			tile2 = ImageIO.read(Main.class.getResourceAsStream("tile2.png"));
		} catch (IOException ex)
		{
			ex.printStackTrace();
		}
		
    		/*
		 * Create the map (I.e. the larger image)
		 * For the sake of this example, only creating a larger image that is two tiles wide
		 * by one tile tall. This is why the first parameter in "new BufferedImage(..." is 
		 * the tile's width * 2, and the second is the tile's height.
		 */
		int mapWidth = tile1.getWidth() * 2;
		
		int mapHeight = tile1.getHeight();
		
		map = new BufferedImage(mapWidth, mapHeight, BufferedImage.TYPE_INT_ARGB);
		
    		// Get the class for painting the smaller images onto the large one.
		Graphics2D g = map.createGraphics();
		
    		// Draw the first tile.
		g.drawImage(tile1, 0, 0, null);
		
		//"Translate" or "Move" to the right far enough to draw the next tile (tile2).
		//The parameters are (x, y) so tile2.getWidth() tells the Graphics2D
		//object to move to the right the same amount of pixels as the "tile2" 
		//image is wide. (E.g. if tile2 width == 16, then the Graphics2D will
		//move it's cursor 16 pixels to the right.)
		//For x, a positive number goes right, negative goes left.
		//For y, a positive goes down, and a negative goes up.
		g.translate(tile2.getWidth(), 0);
		
   		//Draw the second image.
		g.drawImage(tile2, 0, 0, null);
		
    		//Close the Graphics2D object.
		g.dispose();
		
    		//Optional, merely shows the finished product in a dialog.
		JOptionPane.showMessageDialog(null, new ImageIcon(map));
	}

}