From f0fdd66ba4fa07d5ef314eab9aee404750ae3ef4 Mon Sep 17 00:00:00 2001
From: Mark Wielaard <mark@klomp.org>
Date: Sat, 20 Oct 2001 06:26:45 +0000
Subject: Double.java: More Classpath merging

	* java/lang/Double.java: More Classpath merging
	(isInfinite): Don't use doubleToLongBits
	(isNaN (Object)): return v != v
	(initIDs): make native
	* java/lang/Float.java: Ditto
	(isInfinite): Don't use floatToIntBits
	(isNaN (Object)): return v != v
	* java/lang/natDouble.cc: add empty initIDs()

From-SVN: r46370
---
 libjava/java/lang/Float.java | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

(limited to 'libjava/java/lang/Float.java')

diff --git a/libjava/java/lang/Float.java b/libjava/java/lang/Float.java
index 91da0754d60..9e26143f773 100644
--- a/libjava/java/lang/Float.java
+++ b/libjava/java/lang/Float.java
@@ -215,6 +215,14 @@ public final class Float extends Number implements Comparable
    * <code>instanceof</code> <code>Float</code>, and represents
    * the same primitive <code>float</code> value return 
    * <code>true</code>.  Otherwise <code>false</code> is returned.
+   * <p>
+   * Note that there are two differences between <code>==</code> and
+   * <code>equals()</code>. <code>0.0f == -0.0f</code> returns <code>true</code>
+   * but <code>new Float(0.0f).equals(new Float(-0.0f))</code> returns
+   * <code>false</code>. And <code>Float.NaN == Float.NaN</code> returns
+   * <code>false</code>, but
+   * <code>new Float(Float.NaN).equals(new Float(Float.NaN))</code> returns
+   * <code>true</code>.
    *
    * @param obj the object to compare to
    * @return whether the objects are semantically equal.
@@ -364,11 +372,9 @@ public final class Float extends Number implements Comparable
    */
   public static boolean isNaN (float v)
   {
-    int bits = floatToIntBits (v);
-    int e = bits & 0x7f800000;
-    int f = bits & 0x007fffff;
-
-    return e == 0x7f800000 && f != 0;
+    // This works since NaN != NaN is the only reflexive inequality
+    // comparison which returns true.
+    return v != v;
   }
 
   /**
@@ -393,10 +399,7 @@ public final class Float extends Number implements Comparable
    */
   public static boolean isInfinite (float v)
   {
-    int bits = floatToIntBits (v);
-    int f = bits & 0x7fffffff;
-
-    return f == 0x7f800000;
+    return (v == POSITIVE_INFINITY || v == NEGATIVE_INFINITY);
   }
 
   /**
-- 
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