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 }
Object->Number(Serializable)->Double
Double.valueOf()