Java in a Nutshell

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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()


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