
Java Platform 1.2 Beta 4 

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SUMMARY: INNER  FIELD  CONSTR  METHOD  DETAIL: FIELD  CONSTR  METHOD 
java.lang.Object  +java.lang.Number  +java.lang.Float
float
in
an object. An object of type Float
contains a single
field whose type is float
.
In addition, this class provides several methods for converting a
float
to a String
and a
String
to a float
, as well as other
constants and methods useful when dealing with a
float
.
Field Summary  
static float  MAX_VALUE
The largest positive value of type float . 
static float  MIN_VALUE
The smallest positive value of type float . 
static float  NaN
The NaN value of type float . 
static float  NEGATIVE_INFINITY
The negative infinity of type float . 
static float  POSITIVE_INFINITY
The positive infinity of type float . 
static Class  TYPE
The Class object representing the primitive type float. 
static int  WIDEFP_MAX_EXPONENT
If a floatextended format is available to code that has been declared to be or is by default FPwide, this value is the maximum exponent that can be represented in the floatextended format. 
static int  WIDEFP_MIN_EXPONENT
If a floatextended format is available to code that has been declared to be or is by default FPwide, this value is the minimum exponent that can be represented in the floatextended format. 
static int  WIDEFP_SIGNIFICAND_BITS
If a floatextended format is available to code that has been declared to be or is by default FPwide, this value is the number of bits of significand that can be represented in the floatextended format. 
Constructor Summary  
Float(double value)
Constructs a newly allocated Float object that
represents the argument converted to type float . 

Float(float value)
Constructs a newly allocated Float object that
represents the primitive float argument. 

Float(String s)
Constructs a newly allocated Float object that
represents the floating point value of type float
represented by the string. 
Method Summary  
byte  byteValue()
Returns the value of this Float as a byte (by casting to a byte). 
int  compareTo(Float anotherFloat)
Compares two Floats numerically. 
int  compareTo(Object o)
Compares this Float to another Object. 
double  doubleValue()
Returns the double value of this Float. 
boolean  equals(Object obj)
Compares this object against some other object. 
static int  floatToIntBits(float value)
Returns the bit represention of a singlefloat value. 
float  floatValue()
Returns the float value of this Float object. 
int  hashCode()
Returns a hashcode for this Float. 
static float  intBitsToFloat(int bits)
Returns the singlefloat corresponding to a given bit represention. 
int  intValue()
Returns the integer value of this Float (by casting to an int). 
boolean  isInfinite()
Returns true if this Float value is infinitely large in magnitude. 
static boolean  isInfinite(float v)
Returns true if the specified number is infinitely large in magnitude. 
boolean  isNaN()
Returns true if this Float value is NotaNumber (NaN). 
static boolean  isNaN(float v)
Returns true if the specified number is the special NotaNumber (NaN) value. 
long  longValue()
Returns the long value of this Float (by casting to a long). 
short  shortValue()
Returns the value of this Float as a short (by casting to a short). 
String  toString()
Returns a String representation of this Float object. 
static String  toString(float f)
Returns a String representation for the specified float value. 
static Float  valueOf(String s)
Returns the floating point value represented by the specified String. 
Methods inherited from class java.lang.Object  
clone , finalize , getClass , notify , notifyAll , wait , wait , wait 
Field Detail 
public static final float POSITIVE_INFINITY
float
.public static final float NEGATIVE_INFINITY
float
.public static final float NaN
float
.public static final float MAX_VALUE
float
.public static final float MIN_VALUE
float
.public static final int WIDEFP_SIGNIFICAND_BITS
public static final int WIDEFP_MIN_EXPONENT
public static final int WIDEFP_MAX_EXPONENT
public static final Class TYPE
Constructor Detail 
public Float(float value)
Float
object that
represents the primitive float
argument.
value
 the value to be represented by the Float
.public Float(double value)
Float
object that
represents the argument converted to type float
.
value
 the value to be represented by the Float
.public Float(String s) throws NumberFormatException
Float
object that
represents the floating point value of type float
represented by the string. The string is converted to a
float
value as if by the valueOf
method.
s
 a string to be converted to a Float
.valueOf(java.lang.String)
Method Detail 
public static String toString(float f)
The values NaN
, NEGATIVE_INFINITY
,
POSITIVE_INFINITY
, 0.0
, and
+0.0
are represented by the strings
"NaN"
, "Infinity"
,
"Infinity"
, "0.0"
, and
"0.0"
, respectively.
If d
is in the range
10^{3} <=
d <= 10^{7}
,
then it is converted to a String
in the style
[]ddd.ddd
. Otherwise, it is converted to a
string in the style []m.ddddE±xx
.
There is always a minimum of 1 digit after the decimal point. The
number of digits is the minimum needed to uniquely distinguish the
argument value from adjacent values of type float
.
d
 the float to be converted.public static Float valueOf(String s) throws NumberFormatException
s
 the string to be parsed.Float
initialized to the
value represented by the String
argument.public static boolean isNaN(float v)
v
 the value to be tested.true
if the argument is NaN;
false
otherwise.public static boolean isInfinite(float v)
v
 the value to be tested.true
if the argument is positive infinity or
negative infinity; false
otherwise.public boolean isNaN()
true
if the value represented by this object is
NaN; false
otherwise.public boolean isInfinite()
true
if the value represented by this object is
positive infinity or negative infinity;
false
otherwise.public String toString()
float
value represented by this object
is converted to a String
exactly as if by the method
toString
of one argument.String
representation of this object.toString(float)
public byte byteValue()
public short shortValue()
public int intValue()
float
value represented by this object
converted to type int
and the result of the
conversion is returned.public long longValue()
float
value represented by this object is
converted to type long
and the result of the
conversion is returned.public float floatValue()
float
value represented by this object.public double doubleValue()
public int hashCode()
public boolean equals(Object obj)
true
if and only if the argument is
not null
and is a Float
object that
represents a float
that has the identical bit pattern
to the bit pattern of the float
represented by this
object.
Note that in most cases, for two instances of class
Float
, f1
and f2
, the value
of f1.equals(f2)
is true
if and only if
f1.floatValue() == f2.floatValue()
also has the value true
. However, there are two exceptions:
f1
and f2
both represent
Float.NaN
, then the equals
method returns
true
, even though Float.NaN==Float.NaN
has the value false
.
f1
represents +0.0f
while
f2
represents 0.0f
, or vice versa,
the equal
test has the value false
,
even though 0.0f==0.0f
has the value true
.
true
if the objects are the same;
false
otherwise.floatToIntBits(float)
public static int floatToIntBits(float value)
Bit 31 represents the sign of the floatingpoint number. Bits 3023 represent the exponent. Bits 220 represent the significand (sometimes called the mantissa) of the floatingpoint number.
If the argument is positive infinity, the result is
0x7f800000
.
If the argument is negative infinity, the result is
0xff800000
.
If the argument is NaN, the result is 0x7fc00000
.
value
 a floatingpoint number.public static float intBitsToFloat(int bits)
If the argument is 0x7f800000
, the result is positive
infinity.
If the argument is 0xff800000
, the result is negative
infinity.
If the argument is any value in the range 0x7f800001
through 0x7f8fffff
or in the range
0xff800001
through 0xff8fffff
, the result is
NaN. All IEEE 754 NaN values are, in effect, lumped together by
the Java language into a single value.
bits
 an integer.public int compareTo(Float anotherFloat)
anotherFloat
 the Float
to be compared.0
if the argument Float is equal to
this Float; a value less than 0
if this Float
is numerically less than the Float argument; and a
value greater than 0
if this Float is
numerically greater than the Float argument
(signed comparison).public int compareTo(Object o)
compareTo(Float)
. Otherwise,
it throws a ClassCastException
(as Floats are comparable
only to other Floats).
o
 the Object
to be compared.0
if the argument is a Float
numerically equal to this Float; a value less than
0
if the argument is a Float numerically
greater than this Float; and a value greater than
0
if the argument is a Float numerically
less than this Float.ClassCastException
 if the argument is not a
Float
.Comparable

Java Platform 1.2 Beta 4 

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