Source code below will show you, how to set JButton background color base on RGB. You can get RGB value for your color using "Color picker" at above.

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COMPLETE SOURCE CODE FOR : SetJButtonBackgroundColor.java
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import javax.swing.JButton;
import javax.swing.JFrame;

import java.awt.Color;
import java.awt.FlowLayout;

public class SetJButtonBackgroundColor
{
public static void main(String[]args)
{
 //Create button using JButton
 JButton button=new JButton("Click me");

 //Create JFrame with title ( Set JButton background color )
 JFrame frame=new JFrame("Set JButton background color");

 //Set JFrame layout to FlowLayout
 frame.setLayout(new FlowLayout());

 //Set color base on RGB
 //You can get RGB value for your color at "Color picker" at above
 //R=255
 //G=0
 //B=0
 Color color=new Color(255,0,0);

 //Set JButton background color to color that you choose
 button.setBackground(color);

 //Add JButton into JFrame
 frame.add(button);

 //Set default close operation for JFrame
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(500,300);

 //Make JFrame visible
 frame.setVisible(true);
}
}


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JUST COMPILE AND EXECUTE IT
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