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Java in a Nutshell

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25.17 java.lang.Double (JDK 1.0)

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

This class also provides some useful constants and static methods for testing double 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 double or a Double has an infinite value. Similarly, isNaN() tests whether a double or Double 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. doubleToLongBits() and longBitsToDouble() allow you to manipulate the bit representation of a double directly.

public final class Double extends Number {
    // Public Constructors
            public Double(double value);
            public Double(String s) throws NumberFormatException;
    // Constants
            public static final double MAX_VALUE;
            public static final double MIN_VALUE;
            public static final double NEGATIVE_INFINITY;
            public static final double NaN;
            public static final double POSITIVE_INFINITY;
        1.1public static final Class TYPE;
    // Class Methods
            public static native long doubleToLongBits(double value);
            public static boolean isInfinite(double v);
            public static boolean isNaN(double v);
            public static native double longBitsToDouble(long bits);
            public static String toString(double d);
            public static Double 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)->Double

Returned By:

Double.valueOf()


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