I am trying to change color value to color hexa code. So, I code like this:
color = Integer.toHexString(colorpick.getValue().hashCode()).substring(0, 6).toUpperCase();
The above code is Ok for all colors except for "Black" color.
It gives the following error for "Black" color.
String index out of range : 6 error
Is any solution for my problem, please?
this is absolutely wrong here:
colorpick.getValue().hashCode()
hashcode is a specific code generated by the JVM to manage hash numbers related to instances and hash-tables... and has NOTHING to do with colors..
this should be more than ok
colorpick.getValue()
System.out.println(Integer.toHexString(Color.BLACK.hashCode()));, It give me result ff000000. So, I think that the problem is not from hashCode().int java.awt.Color.hashCode(). So, It is related for use.
Since you did not mention what class the variable "colorpick" is, I'm going to assume it's ColorPicker (https://docs.oracle.com/javase/8/javafx/api/javafx/scene/control/ColorPicker.html).
I don't think its hashcode() method is overriden to return the RGB value in hex.
The cause of your error is that black's RGB value is 0. Applying .toHexString() will only give you "0", a single character, hence the .substring() will not work. Other RGB values may also result in a string shorter than 6.
I assume you want the result to be always 6-digit; then you should pad the string with 0 from the start if it's shorter.
Edit ColorPicker.getValue() returns a Color object, not the RGB value. So you should use colorpick.getValue().getRGB() instead.
https://docs.oracle.com/javase/7/docs/api/java/awt/Color.html#getRGB()
Edit2
With and without .getRGB():
Color c = Color.CYAN;
String s = Integer.toHexString(c.getRGB() & 0xFFFFFF).toUpperCase();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < 6 - s.length(); i++) {
sb.append("0");
}
sb.append(s);
System.out.println(sb.toString());
Color c = Color.CYAN;
int rgbValue = (c.getRed() << 16) + (c.getGreen() << 8) + c.getBlue();
String s = Integer.toHexString(rgbValue & 0xFFFFFF).toUpperCase();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < 6 - s.length(); i++) {
sb.append("0");
}
sb.append(s);
System.out.println(sb.toString());
use try catch function to handle it. if error hexa
colorpick.getValue(). I think, the problem come from that part.