For anyone wondering, how to set something up, here is some code for you 
(Recursive algorithm)
I haven’t added comments, nor I will add any explanation. If you don’t know, what Perlin’s Noise is, that code is not for you 
Google it 
Also, I’ts posted in Shared Code, so I think, thats okey
package /*TOP-SECRET*/
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
public class PerlinNoise2D {
private float[][] values;
private float roughness;
private float varyation;
private Random rand;
public PerlinNoise2D(int size, float roughness, float varyation, float seed, Random rand) {
this.roughness = roughness;
this.varyation = varyation;
this.rand = rand;
int realsize = 1;
while(realsize < size) {
realsize *= 2;
}
realsize += 1;
values = new float[realsize][realsize];
int firststep = realsize/2;
values[0][0] = seed;
values[realsize-1][0] = seed;
values[0][realsize-1] = seed;
values[realsize-1][realsize-1] = seed;
values[0][firststep] = seed;
values[firststep][0] = seed;
values[firststep][firststep] = seed;
values[firststep][realsize-1] = seed;
values[realsize-1][firststep] = seed;
noise(0, 0, realsize-1);
}
private void noise(int x, int y, int step) {
if (step > 1) {
int halfStep = step/2;
float vary = (step*varyation)*roughness;
values[x+halfStep][y] = values[x+halfStep][y] == 0f ?
vary(mid(values[x][y], values[x+step][y]), vary) : values[x+halfStep][y];
values[x][y+halfStep] = values[x][y+halfStep] == 0f ?
vary(mid(values[x][y], values[x][y+step]), vary) : values[x][y+halfStep];
values[x+step][y+halfStep] = values[x+step][y+halfStep] == 0f ?
vary(mid(values[x+step][y], values[x+step][y+step]), vary) : values[x+step][y+halfStep];
values[x+halfStep][y+step] = values[x+halfStep][y+step] == 0f ?
vary(mid(values[x][y+step], values[x+step][y+step]), vary) : values[x+halfStep][y+step];
values[x+halfStep][y+halfStep] = vary(mid(
values[x][y],
values[x+halfStep][y],
values[x+step][y],
values[x][y+halfStep],
values[x+step][y+halfStep],
values[x][y+step],
values[x+halfStep][y+step],
values[x+step][y+step]), vary);
noise(x, y, halfStep);
noise(x+halfStep, y, halfStep);
noise(x, y+halfStep, halfStep);
noise(x+halfStep, y+halfStep, halfStep);
}
}
public float randRange(float range, Random rand) {
return rand.nextBoolean() ? -rand.nextFloat()*range : rand.nextFloat()*range;
}
public float vary(float val, float vary) {
return val+randRange(vary, rand);
}
public float mid(float... vals) {
float sum = 0;
for (int i = 0; i < vals.length; i++) {
sum += vals[i];
}
return sum / vals.length;
}
public float[][] get() {
return values;
}
public static void main(String[] args) {
System.out.println("Started.");
int size = 512;
PerlinNoise2D pn2d = new PerlinNoise2D(size, 0.4f, 1, 20000f, new Random());
float[][] vals = pn2d.get();
BufferedImage img = new BufferedImage(size+1, size+1, BufferedImage.TYPE_INT_ARGB);
for (int x = 0; x < vals.length; x++) {
for (int y = 0; y < vals[x].length; y++) {
img.setRGB(x, y, ((int)vals[x][y]) | 0xFF000000);
}
}
try {
saveImg(new File("Heightmap.png"), img);
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Finished.");
}
public static void saveImg(File f, BufferedImage img) throws IOException {
f.createNewFile();
ImageIO.write(img, "PNG", f);
}
}
