File	Doc	Category	Size	Date	Package
Float.java	API Doc	phoneME MR2 API (J2ME)	23689	Wed May 02 17:59:56 BST 2007	java.lang

Float

• java.lang.Object

Fields Summary
public static final float	POSITIVE_INFINITY The positive infinity of type float. It is equal to the value returned by Float.intBitsToFloat(0x7f800000).
public static final float	NEGATIVE_INFINITY The negative infinity of type float. It is equal to the value returned by Float.intBitsToFloat(0xff800000).
public static final float	NaN The Not-a-Number (NaN) value of type float. It is equal to the value returned by Float.intBitsToFloat(0x7fc00000).
public static final float	MAX_VALUE The largest positive value of type float. It is equal to the value returned by Float.intBitsToFloat(0x7f7fffff).
public static final float	MIN_VALUE The smallest positive value of type float. It is equal to the value returned by Float.intBitsToFloat(0x1).
private float	value The value of the Float.

Constructors Summary
public Float(float value) Constructs a newly allocated Float object that represents the primitive float argument. param value the value to be represented by the Float. this.value = value;
public Float(double value) Constructs a newly allocated Floatobject that represents the argument converted to type float. param value the value to be represented by the Float. this.value = (float)value;

Methods Summary
public byte	byteValue() Returns the value of this Float as a byte (by casting to a byte). since JDK1.1 return (byte)value;
public double	doubleValue() Returns the double value of this Float object. return the float value represented by this object is converted to type double and the result of the conversion is returned. return (double)value;
public boolean	equals(java.lang.Object obj) Compares this object against some other object. The result is 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. For this purpose, two float values are considered to be the same if and only if the method {@link #floatToIntBits(float)} returns the same int value when applied to each. 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: If f1 and f2 both represent Float.NaN, then the equals method returns true, even though Float.NaN==Float.NaN has the value false. If 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. This definition allows hashtables to operate properly. param obj the object to be compared return true if the objects are the same; false otherwise. see java.lang.Float#floatToIntBits(float) return (obj instanceof Float) && (floatToIntBits(((Float)obj).value) == floatToIntBits(value));
public static native int	floatToIntBits(float value) Returns the bit representation of a single-float value. The result is a representation of the floating-point argument according to the IEEE 754 floating-point "single precision" bit layout. Bit 31 (the bit that is selected by the mask 0x80000000) represents the sign of the floating-point number. Bits 30-23 (the bits that are selected by the mask 0x7f800000) represent the exponent. Bits 22-0 (the bits that are selected by the mask 0x007fffff) represent the significand (sometimes called the mantissa) of the floating-point 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. In all cases, the result is an integer that, when given to the {@link #intBitsToFloat(int)} method, will produce a floating-point value equal to the argument to floatToIntBits. param value a floating-point number. return the bits that represent the floating-point number.
public float	floatValue() Returns the float value of this Float object. return the float value represented by this object. return value;
public int	hashCode() Returns a hashcode for this Float object. The result is the integer bit representation, exactly as produced by the method {@link #floatToIntBits(float)}, of the primitive float value represented by this Float object. return a hash code value for this object. return floatToIntBits(value);
public static native float	intBitsToFloat(int bits) Returns the single-float corresponding to a given bit representation. The argument is considered to be a representation of a floating-point value according to the IEEE 754 floating-point "single precision" bit layout. 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 0x7fffffff or in the range 0xff800001 through 0xffffffff, the result is NaN. All IEEE 754 NaN values of type float are, in effect, lumped together by the Java programming language into a single float value called NaN. In all other cases, let s, e, and m be three values that can be computed from the argument: int s = ((bits >> 31) == 0) ? 1 : -1; int e = ((bits >> 23) & 0xff); int m = (e == 0) ? (bits & 0x7fffff) << 1 : (bits & 0x7fffff) | 0x800000; Then the floating-point result equals the value of the mathematical expression s·m·2e-150. param bits an integer. return the single-format floating-point value with the same bit pattern.
public int	intValue() Returns the integer value of this Float (by casting to an int). return the float value represented by this object converted to type int and the result of the conversion is returned. return (int)value;
public static boolean	isInfinite(float v) Returns true if the specified number is infinitely large in magnitude. param v the value to be tested. return true if the argument is positive infinity or negative infinity; false otherwise. return (v == POSITIVE_INFINITY) || (v == NEGATIVE_INFINITY);
public boolean	isInfinite() Returns true if this Float value is infinitely large in magnitude. return true if the value represented by this object is positive infinity or negative infinity; false otherwise. return isInfinite(value);
public static boolean	isNaN(float v) Returns true if the specified number is the special Not-a-Number (NaN) value. param v the value to be tested. return true if the argument is NaN; false otherwise. return (v != v);
public boolean	isNaN() Returns true if this Float value is Not-a-Number (NaN). return true if the value represented by this object is NaN; false otherwise. return isNaN(value);
public long	longValue() Returns the long value of this Float (by casting to a long). return the float value represented by this object is converted to type long and the result of the conversion is returned. return (long)value;
public static float	parseFloat(java.lang.String s) Returns a new float initialized to the value represented by the specified String. param s the string to be parsed. return the float value represented by the string argument. exception NumberFormatException if the string does not contain a parsable float. since JDK1.2 return FloatingDecimal.readJavaFormatString(s).floatValue();
public short	shortValue() Returns the value of this Float as a short (by casting to a short). since JDK1.1 return (short)value;
public static java.lang.String	toString(float f) Returns a String representation for the specified float value. The argument is converted to a readable string format as follows. All characters and characters in strings mentioned below are ASCII characters. If the argument is NaN, the result is the string "NaN". Otherwise, the result is a string that represents the sign and magnitude (absolute value) of the argument. If the sign is negative, the first character of the result is '-' ('\u002d'); if the sign is positive, no sign character appears in the result. As for the magnitude m: If m is infinity, it is represented by the characters "Infinity"; thus, positive infinity produces the result "Infinity" and negative infinity produces the result "-Infinity". If m is zero, it is represented by the characters "0.0"; thus, negative zero produces the result "-0.0" and positive zero produces the result "0.0". If m is greater than or equal to 10-3 but less than 107, then it is represented as the integer part of m, in decimal form with no leading zeroes, followed by '.' (\u002E), followed by one or more decimal digits representing the fractional part of m. If m is less than 10-3 or not less than 107, then it is represented in so-called "computerized scientific notation." Let n be the unique integer such that 10n<=m<1; then let a be the mathematically exact quotient of m and 10n so that 1<a<10. The magnitude is then represented as the integer part of a, as a single decimal digit, followed by '.' (\u002E), followed by decimal digits representing the fractional part of a, followed by the letter 'E' (\u0045), followed by a representation of n as a decimal integer, as produced by the method {@link java.lang.Integer#toString(int)} of one argument. How many digits must be printed for the fractional part of m or a? There must be at least one digit to represent the fractional part, and beyond that as many, but only as many, more digits as are needed to uniquely distinguish the argument value from adjacent values of type float. That is, suppose that x is the exact mathematical value represented by the decimal representation produced by this method for a finite nonzero argument f. Then f must be the float value nearest to x; or, if two float values are equally close to xthen f must be one of them and the least significant bit of the significand of f must be 0. param f the float to be converted. return a string representation of the argument. return new FloatingDecimal(f).toJavaFormatString();
public java.lang.String	toString() Returns a String representation of this Float object. The primitive float value represented by this object is converted to a String exactly as if by the method toString of one argument. return a String representation of this object. see java.lang.Float#toString(float) return String.valueOf(value);
public static java.lang.Float	valueOf(java.lang.String s) Returns the floating point value represented by the specified String. The string s is interpreted as the representation of a floating-point value and a Float object representing that value is created and returned. If s is null, then a NullPointerException is thrown. Leading and trailing whitespace characters in s are ignored. The rest of s should constitute a FloatValue as described by the lexical syntax rules: FloatValue: Signopt FloatingPointLiteral where Sign, FloatingPointLiteral are as defined in Section 3.10.2 of the Java Language Specification. If it does not have the form of a FloatValue, then a NumberFormatException is thrown. Otherwise, it is regarded as representing an exact decimal value in the usual "computerized scientific notation"; this exact decimal value is then conceptually converted to an "infinitely precise" binary value that is then rounded to type float by the usual round-to-nearest rule of IEEE 754 floating-point arithmetic. param s the string to be parsed. return a newly constructed Float initialized to the value represented by the String argument. exception NumberFormatException if the string does not contain a parsable number. return new Float(FloatingDecimal.readJavaFormatString(s).floatValue());