Merge branch 'develop' into bug/JAL-2255_seq-fetcher-broken-on-linux

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

diff --git a/src/jalview/util/Format.java b/src/jalview/util/Format.java
index d14e4ad..bf52027 100755 (executable)
--- a/src/jalview/util/Format.java
+++ b/src/jalview/util/Format.java
@@ -26,6 +26,8 @@
  */
 package jalview.util;
 
+import java.util.Arrays;
+
 /**
  * DOCUMENT ME!
  * 
@@ -664,30 +666,22 @@ public class Format
   }
 
   /**
-   * DOCUMENT ME!
+   * Returns a string consisting of n repeats of character c
    * 
    * @param c
-   *          DOCUMENT ME!
    * @param n
-   *          DOCUMENT ME!
    * 
-   * @return DOCUMENT ME!
+   * @return
    */
-  private static String repeat(char c, int n)
+  static String repeat(char c, int n)
   {
     if (n <= 0)
     {
       return "";
     }
-
-    StringBuffer s = new StringBuffer(n);
-
-    for (int i = 0; i < n; i++)
-    {
-      s.append(c);
-    }
-
-    return s.toString();
+    char[] chars = new char[n];
+    Arrays.fill(chars, c);
+    return new String(chars);
   }
 
   /**
@@ -890,21 +884,18 @@ public class Format
     String f = "";
     int e = 0;
     double dd = d;
-    double factor = 1;
 
     if (d != 0)
     {
       while (dd > 10)
       {
         e++;
-        factor /= 10;
         dd = dd / 10;
       }
 
       while (dd < 1)
       {
         e--;
-        factor *= 10;
         dd = dd * 10;
       }
     }
@@ -914,8 +905,7 @@ public class Format
       return fixed_format(d);
     }
 
-    d = d * factor;
-    f = f + fixed_format(d);
+    f = f + fixed_format(dd);
 
     if ((fmt == 'e') || (fmt == 'g'))
     {
@@ -947,4 +937,49 @@ public class Format
   {
     return formatString;
   }
+
+  /**
+   * Bespoke method to format percentage float value to the specified number of
+   * decimal places. Avoids use of general-purpose format parsers as a
+   * processing hotspot.
+   * 
+   * @param sb
+   * @param value
+   * @param dp
+   */
+  public static void appendPercentage(StringBuilder sb, float value, int dp)
+  {
+    /*
+     * rounding first
+     */
+    double d = value;
+    long factor = 1L;
+    for (int i = 0; i < dp; i++)
+    {
+      factor *= 10;
+    }
+    d *= factor;
+    d += 0.5;
+
+    /*
+     * integer part
+     */
+    value = (float) (d / factor);
+    sb.append((long) value);
+
+    /*
+     * decimal places
+     */
+    if (dp > 0)
+    {
+      sb.append(".");
+      while (dp > 0)
+      {
+        value = value - (int) value;
+        value *= 10;
+        sb.append((int) value);
+        dp--;
+      }
+    }
+  }
 }