JAL-3368 removed parsing web colours (now on a separate branch)

[jalview.git] / src / jalview / util / StringUtils.java

diff --git a/src/jalview/util/StringUtils.java b/src/jalview/util/StringUtils.java
index 2e8ace8..2cbbfbf 100644 (file)
--- a/src/jalview/util/StringUtils.java
+++ b/src/jalview/util/StringUtils.java
@@ -146,7 +146,7 @@ public class StringUtils
     {
       return null;
     }
-    List<String> jv = new ArrayList<String>();
+    List<String> jv = new ArrayList<>();
     int cp = 0, pos, escape;
     boolean wasescaped = false, wasquoted = false;
     String lstitem = null;
@@ -444,4 +444,30 @@ public class StringUtils
     }
     return text;
   }
+
+  /**
+   * Answers true if the string is not empty and consists only of digits, or
+   * characters 'a'-'f' or 'A'-'F', else false
+   * 
+   * @param s
+   * @return
+   */
+  public static boolean isHexString(String s)
+  {
+    int j = s.length();
+    if (j == 0)
+    {
+      return false;
+    }
+    for (int i = 0; i < j; i++)
+    {
+      int c = s.charAt(i);
+      if (!(c >= '0' && c <= '9') && !(c >= 'a' && c <= 'f')
+              && !(c >= 'A' && c <= 'F'))
+      {
+        return false;
+      }
+    }
+    return true;
+  }
 }