在java中将颜色名称转换为RGB值

当颜色名称作为输入时，我想要RGB值。 以下代码适用于某些颜色（我猜是原色如RED）而其他一些颜色则失败（如CYAN，MAUVE）

import java.awt.Color; import javax.swing.text.html.StyleSheet; public class ColourTest { public static void main(String[] args) { StyleSheet s = new StyleSheet(); String colourName="RED"; Color clr = s.stringToColor(colourName); int r=clr.getRed(); int g=clr.getGreen(); int b=clr.getBlue(); System.out.println("red:" + r + " green :" + g + " blue:" + b); } } 

有没有其他方法来获取颜色名称的RGB值？

Answer 1

这是我在javax.swing.text.html.CSS类中找到的内容

 /** * Convert a color string such as "RED" or "#NNNNNN" or "rgb(r, g, b)" * to a Color. */ static Color stringToColor(String str) { Color color; if (str == null) { return null; } if (str.length() == 0) color = Color.black; else if (str.startsWith("rgb(")) { color = parseRGB(str); } else if (str.charAt(0) == '#') color = hexToColor(str); else if (str.equalsIgnoreCase("Black")) color = hexToColor("#000000"); else if(str.equalsIgnoreCase("Silver")) color = hexToColor("#C0C0C0"); else if(str.equalsIgnoreCase("Gray")) color = hexToColor("#808080"); else if(str.equalsIgnoreCase("White")) color = hexToColor("#FFFFFF"); else if(str.equalsIgnoreCase("Maroon")) color = hexToColor("#800000"); else if(str.equalsIgnoreCase("Red")) color = hexToColor("#FF0000"); else if(str.equalsIgnoreCase("Purple")) color = hexToColor("#800080"); else if(str.equalsIgnoreCase("Fuchsia")) color = hexToColor("#FF00FF"); else if(str.equalsIgnoreCase("Green")) color = hexToColor("#008000"); else if(str.equalsIgnoreCase("Lime")) color = hexToColor("#00FF00"); else if(str.equalsIgnoreCase("Olive")) color = hexToColor("#808000"); else if(str.equalsIgnoreCase("Yellow")) color = hexToColor("#FFFF00"); else if(str.equalsIgnoreCase("Navy")) color = hexToColor("#000080"); else if(str.equalsIgnoreCase("Blue")) color = hexToColor("#0000FF"); else if(str.equalsIgnoreCase("Teal")) color = hexToColor("#008080"); else if(str.equalsIgnoreCase("Aqua")) color = hexToColor("#00FFFF"); else if(str.equalsIgnoreCase("Orange")) color = hexToColor("#FF8000"); else color = hexToColor(str); // sometimes get specified without leading # return color; } 

因此，如果您传递上面代码中不存在的任何颜色，您将很遗憾地得到NullPointerException

但是，我找到了解决问题的方法。 使用此代码：

 public static void main(String[] args) { StyleSheet s = new StyleSheet(); String colourName = "Cyan"; Color clr = stringToColorCustom(colourName); int r = clr.getRed(); int g = clr.getGreen(); int b = clr.getBlue(); System.out.println("red:" + r + " green :" + g + " blue:" + b); } static Color stringToColorCustom(String str) { Color color; if (str == null) { return null; } if (str.length() == 0) color = Color.black; else if (str.charAt(0) == '#') color = hexToColor(str); else if (str.equalsIgnoreCase("Black")) color = hexToColor("#000000"); else if (str.equalsIgnoreCase("Silver")) color = hexToColor("#C0C0C0"); else if (str.equalsIgnoreCase("Gray")) color = hexToColor("#808080"); else if (str.equalsIgnoreCase("White")) color = hexToColor("#FFFFFF"); else if (str.equalsIgnoreCase("Maroon")) color = hexToColor("#800000"); else if (str.equalsIgnoreCase("Red")) color = hexToColor("#FF0000"); else if (str.equalsIgnoreCase("Purple")) color = hexToColor("#800080"); else if (str.equalsIgnoreCase("Fuchsia")) color = hexToColor("#FF00FF"); else if (str.equalsIgnoreCase("Green")) color = hexToColor("#008000"); else if (str.equalsIgnoreCase("Lime")) color = hexToColor("#00FF00"); else if (str.equalsIgnoreCase("Olive")) color = hexToColor("#808000"); else if (str.equalsIgnoreCase("Yellow")) color = hexToColor("#FFFF00"); else if (str.equalsIgnoreCase("Navy")) color = hexToColor("#000080"); else if (str.equalsIgnoreCase("Blue")) color = hexToColor("#0000FF"); else if (str.equalsIgnoreCase("Teal")) color = hexToColor("#008080"); else if (str.equalsIgnoreCase("Aqua")) color = hexToColor("#00FFFF"); else if (str.equalsIgnoreCase("Orange")) color = hexToColor("#FF8000"); else if (str.equalsIgnoreCase("Cyan")) // Add your color color = hexToColor("#00FFFF"); // Add the RGB else color = hexToColor(str); // sometimes get specified // without leading # return color; } static final Color hexToColor(String value) { String digits; int n = value.length(); if (value.startsWith("#")) { digits = value.substring(1, Math.min(value.length(), 7)); } else { digits = value; } String hstr = "0x" + digits; Color c; try { c = Color.decode(hstr); } catch (NumberFormatException nfe) { c = null; } return c; } 

在上面的代码中，我创建了一个自定义的stringToColorCustom方法，现在我可以在该方法中添加我想要的任何颜色。

希望能帮助到你！

Answer 2

我建议通过HashMap使用一种翻译表：

  HashMap table = new HashMap<>(); table.put(new NamedColor("red"), new RgbColor("#ff0000")); table.put(new NamedColor("blue"), new RgbColor("#0000ff")); 

转换如何运作：

 class ColorConverter { // if you need reverse color conversion you can use handy bidirectoinal // maps from http://commons.apache.org/proper/commons-collections/javadocs/api-release/org/apache/commons/collections4/bidimap/DualHashBidiMap.html private HashMap table; public static RgbColor convert(NamedColor color) { return table.get(color); } 

根据您的需要调整此大纲。