src/java.base/share/classes/java/lang/StringLatin1.java

*** 146,155 ****
--- 146,168 ----
              }
          }
          return len1 - len2;
      }
  
+     /**
+      * hashCode consistent with {@link #compareToCI}
+      */
+     public static int hashCodeCI(byte[] value) {
+         int h = 0;
+         for (byte v : value) {
+             char cu = (char) CharacterDataLatin1.instance.toUpperCase(v & 0xff);
+             char cl = (char) CharacterDataLatin1.instance.toLowerCase(cu);
+             h = 31 * h + cl;
+         }
+         return h;
+     }
+ 
      public static int compareToCI_UTF16(byte[] value, byte[] other) {
          int len1 = length(value);
          int len2 = StringUTF16.length(other);
          int lim = Math.min(len1, len2);
          for (int k = 0; k < lim; k++) {