src/share/classes/java/lang/Double.java

@@ -274,11 +274,11 @@
         /*
          * Modeled after the "a" conversion specifier in C99, section
          * 7.19.6.1; however, the output of this method is more
          * tightly specified.
          */
-        if (!FpUtils.isFinite(d) )
+        if (!isFinite(d) )
             // For infinity and NaN, use the decimal output.
             return Double.toString(d);
         else {
             // Initialized to maximum size of output.
             StringBuffer answer = new StringBuffer(24);

@@ -546,11 +546,11 @@
      *
      * @param   v   the value to be tested.
      * @return  {@code true} if the value of the argument is NaN;
      *          {@code false} otherwise.
      */
-    static public boolean isNaN(double v) {
+    public static boolean isNaN(double v) {
         return (v != v);
     }
 
     /**
      * Returns {@code true} if the specified number is infinitely

@@ -558,15 +558,29 @@
      *
      * @param   v   the value to be tested.
      * @return  {@code true} if the value of the argument is positive
      *          infinity or negative infinity; {@code false} otherwise.
      */
-    static public boolean isInfinite(double v) {
+    public static boolean isInfinite(double v) {
         return (v == POSITIVE_INFINITY) || (v == NEGATIVE_INFINITY);
     }
 
     /**
+     * Returns {@code true} if the argument is a finite floating-point
+     * value; returns {@code false} otherwise (for NaN and infinity
+     * arguments).
+     *
+     * @param d the {@code double} value to be tested
+     * @return {@code true} if the argument is a finite
+     * floating-point value, {@code false} otherwise.
+     * @since 1.8
+     */
+    public static boolean isFinite(double d) {
+        return Math.abs(d) <= DoubleConsts.MAX_VALUE;
+    }
+
+    /**
      * The value of the Double.
      *
      * @serial
      */
     private final double value;