No suitable constructor found for Color(int,int,int,double)
<p>I am trying to edit an image so that it has a "rainbow" edit to it. To do this, I simply want to fill in separate rows to fill the image in with the colors of a rainbow. However, if I were to do this, the colors would cover the image. So, I want to add transparency to my colors. However, when I try to do this I run into the error message as mentioned in the title. Here is my code:</p>

<pre><code> /**
 * This program takes a picutre, and places a special effect on it that colors it similar to how a rainbow would be.
 * 
 * @author Dylan Hubbs
 * @version 08/03/16
 */
import java.awt.*;    
class Rainbow
{
    Rainbow()
    {
    }

    public void rainbowEffect(Picture pictureObj)
    {
        int redValue = 0; int greenValue = 0; int blueValue = 0;
        Pixel rainbowTargetPixel = new Pixel(pictureObj, 0,0);               
        Color rainbowPixelColor = null;
        Color [] rainbowPalette = {new Color(255, 0, 0, .5), new Color(255, 200, 0, .5), Color(255, 255, 0, .5), Color(0, 255, 0, .5), Color(0, 0, 255, .5), new Color(138, 43, 226, .5), new Color(75, 0, 130, .5)};

        for(int y=0; y &lt; pictureObj.getHeight(); y++)
        {
            for(int x = 0; x &lt; pictureObj.getWidth(); x++)
            {
                rainbowTargetPixel = pictureObj.getPixel(x,y);                

                if(y &gt;= 0 &amp;&amp; y &lt;= 50)
                rainbowTargetPixel.setColor(rainbowPalette[0]);
                if(y &gt;= 51 &amp;&amp; y &lt;= 100)
                rainbowTargetPixel.setColor(rainbowPalette[1]);
                if(y &gt;= 101 &amp;&amp; y &lt;= 150)
                rainbowTargetPixel.setColor(rainbowPalette[2]);
                if(y &gt;= 151 &amp;&amp; y &lt;= 200)
                rainbowTargetPixel.setColor(rainbowPalette[3]);
                if(y &gt;= 201 &amp;&amp; y &lt;= 250)
                rainbowTargetPixel.setColor(rainbowPalette[4]);
                if(y &gt;= 251 &amp;&amp; y &lt;= 300)
                rainbowTargetPixel.setColor(rainbowPalette[5]);      
            }
        }

        pictureObj.explore();                                           
        pictureObj.write("RainbowWashingtonMonument.jpg");                 
        pictureObj.show();                                              
    }
}

public class RainbowTester
{
    public static void main(String[] args)
    {
        Picture pictureObj = new Picture("washingtonmonument.jpg");
        pictureObj.explore();
        Rainbow rb = new Rainbow();

        rb.rainbowEffect(pictureObj);
    }
}
</code></pre>

<p>So, the error comes in at </p>

<blockquote>
  <p>{new Color(255, 0, 0, .5)</p>
</blockquote>

<p>And, I'm sure the error would continue on for the other colors in the array. This error does not happen when I try to add the floating value at the end of each method... However, I thought that I could add the floating number for transparency? Please help!</p>