home | O'Reilly's CD bookshelfs | FreeBSD | Linux | Cisco | Cisco Exam    

Java in a Nutshell

Previous Chapter 25
The java.lang Package
Next
 

25.21 java.lang.Float (JDK 1.0)

This class provides an immutable object wrapper around the float primitive data type. valueOf() converts a string to a Float, floatValue() returns the primitive float value of a Float object, and there are methods for returning a Float value as a variety of other primitive types.

This class also provides some useful constants and static methods for testing float values. MIN_VALUE and MAX_VALUE are the smallest (closest to zero) and largest representable double values. isInfinite() in class method and instance method forms tests whether a float or a Float has an infinite value. Similarly, isNaN() tests whether a float or Float is not-a-number--this is a comparison that cannot be done directly because the NaN constant never tests equal to any other value, including itself. floatToIntBits() and intBitsToFloat() allow you to manipulate the bit representation of a float directly.

public final class Float extends Number {
    // Public Constructors
            public Float(float value);
            public Float(double value);
            public Float(String s) throws NumberFormatException;
    // Constants
            public static final float MAX_VALUE;
            public static final float MIN_VALUE;
            public static final float NEGATIVE_INFINITY;
            public static final float NaN;
            public static final float POSITIVE_INFINITY;
        1.1public static final Class TYPE;
    // Class Methods
            public static native int floatToIntBits(float value);
            public static native float intBitsToFloat(int bits);
            public static boolean isInfinite(float v);
            public static boolean isNaN(float v);
            public static String toString(float f);
            public static Float valueOf(String s) throws NumberFormatException;
    // Public Instance Methods
        1.1public byte byteValue();  // Overrides Number
            public double doubleValue();  // Defines Number
            public boolean equals(Object obj);  // Overrides Object
            public float floatValue();  // Defines Number
            public int hashCode();  // Overrides Object
            public int intValue();  // Defines Number
            public boolean isInfinite();
            public boolean isNaN();
            public long longValue();  // Defines Number
        1.1public short shortValue();  // Overrides Number
            public String toString();  // Overrides Object
}

Hierarchy:

Object->Number(Serializable)->Float

Returned By:

Float.valueOf()


Previous Home Next
java.lang.ExceptionInInitializerError (JDK 1.1) Book Index java.lang.IllegalAccessError (JDK 1.0)

Java in a Nutshell Java Language Reference Java AWT Java Fundamental Classes Exploring Java










??????????????@Mail.ru