long.java

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     *
     * @param      s       the <code>String</code> containing the
     *                     <code>long</code>.
     * @param      radix   the radix to be used. 
     * @return     a newly constructed <code>Long</code> initialized to the
     *             value represented by the string argument in the specified
     *             radix.
     * @exception  NumberFormatException  If the <code>String</code> does not
     *               contain a parsable <code>long</code>.
     * @since      JDK1.0
     */
    public static Long valueOf(String s, int radix) throws NumberFormatException {
	return new Long(parseLong(s, radix));
    }

    /**
     * Returns a new long object initialized to the value of the
     * specified String. Throws an exception if the String cannot be
     * parsed as a long. The radix is assumed to be 10.
     *
     * @param      s   the string to be parsed.
     * @return     a newly constructed <code>Long</code> initialized to the
     *             value represented by the string argument.
     * @exception  NumberFormatException  If the <code>String</code> does not
     *               contain a parsable <code>long</code>.
     * @since   JDK1.0
     */
    public static Long valueOf(String s) throws NumberFormatException 
    {
	return new Long(parseLong(s, 10));
    }

    /**
     * The value of the Long.
     */
    private long value;

    /**
     * Constructs a newly allocated <code>Long</code> object that 
     * represents the primitive <code>long</code> argument. 
     *
     * @param   value   the value to be represented by the <code>Long</code>.
     * @since   JDK1.0
     */
    public Long(long value) {
	this.value = value;
    }

    /**
     * Constructs a newly allocated <code>Long</code> object that 
     * represents the value represented by the string. The string is 
     * converted to an <code>long</code> value as if by the 
     * <code>valueOf</code> method. 
     *
     * @param      s   the string to be converted to a <code>Long</code>.
     * @exception  NumberFormatException  if the <code>String</code> does not
     *               contain a parsable long integer.
     * @see        java.lang.Long#valueOf(java.lang.String)
     * @since      JDK1.0
     */
    public Long(String s) throws NumberFormatException {
	this.value = parseLong(s, 10);
    }

    /**
     * Returns the value of this Long as a byte.
     *
     * @since   JDK1.1
     */
    public byte byteValue() {
	return (byte)value;
    }

    /**
     * Returns the value of this Long as a short.
     *
     * @since   JDK1.1
     */
    public short shortValue() {
	return (short)value;
    }

    /**
     * Returns the value of this Long as an int.
     *
     * @return  the <code>long</code> value represented by this object is
     *          converted to type <code>int</code> and the result of the
     *          conversion is returned.
     * @since   JDK1.0
     */
    public int intValue() {
	return (int)value;
    }

    /**
     * Returns the value of this Long as a long.
     *
     * @return  the <code>long</code> value represented by this object.
     * @since   JDK1.0
     */
    public long longValue() {
	return (long)value;
    }

    /**
     * Returns the value of this Long as a float.
     *
     * @return  the <code>long</code> value represented by this object is
     *          converted to type <code>float</code> and the result of
     *          the conversion is returned.
     * @since   JDK1.0
     */
    public float floatValue() {
	return (float)value;
    }

    /**
     * Returns the value of this Long as a double.
     *
     * @return  the <code>long</code> value represented by this object that
     *          is converted to type <code>double</code> and the result of
     *          the conversion is returned.
     * @since   JDK1.0
     */
    public double doubleValue() {
	return (double)value;
    }

    /**
     * Returns a String object representing this Long's value.
     *
     * @return  a string representation of this object in base&nbsp;10.
     * @since   JDK1.0
     */
    public String toString() {
	return String.valueOf(value);
    }

    /**
     * Computes a hashcode for this Long.
     *
     * @return  a hash code value for this object. 
     * @since   JDK1.0
     */
    public int hashCode() {
	return (int)(value ^ (value >> 32));
    }

    /**
     * Compares this object against the specified object.
     * The result is <code>true</code> if and only if the argument is 
     * not <code>null</code> and is a <code>Long</code> object that 
     * contains the same <code>long</code> value as this object. 
     *
     * @param   obj   the object to compare with.
     * @return  <code>true</code> if the objects are the same;
     *          <code>false</code> otherwise.
     * @since   JDK1.0
     */
    public boolean equals(Object obj) {
	if ((obj != null) && (obj instanceof Long)) {
	    return value == ((Long)obj).longValue();
	}
	return false;
    }

    /**
     * Determines the <code>long</code> value of the system property 
     * with the specified name. 
     * <p>
     * The first argument is treated as the name of a system property. 
     * System properties are accessible through <code>getProperty</code>  
     * and , a method defined by the <code>System</code> class. The 
     * string value of this property is then interpreted as a long value 
     * and a <code>Long</code> object representing this value is returned. 
     * Details of possible numeric formats can be found with the 
     * definition of <code>getProperty</code>. 
     * <p>
     * If there is no property with the specified name, or if the 
     * property does not have the correct numeric format, then 
     * <code>null</code> is returned. 
     *
     * @param   nm   property name.
     * @return  the <code>Long</code> value of the property.
     * @see     java.lang.System#getProperty(java.lang.String)
     * @see     java.lang.System#getProperty(java.lang.String, java.lang.String)
     * @since   JDK1.0
     */
    public static Long getLong(String nm) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null)
	    sm.checkPropertyAccess(nm);
	return getLong(nm, null);
    }

    /**
     * Determines the <code>long</code> value of the system property 
     * with the specified name. 
     * <p>
     * The first argument is treated as the name of a system property. 
     * System properties are accessible through <code>getProperty</code>  
     * and , a method defined by the <code>System</code> class. The 
     * string value of this property is then interpreted as a long value 
     * and a <code>Long</code> object representing this value is returned. 
     * Details of possible numeric formats can be found with the 
     * definition of <code>getProperty</code>. 
     * <p>
     * If there is no property with the specified name, or if the 
     * property does not have the correct numeric format, then a 
     * <code>Long</code> object that represents the value of the second 
     * argument is returned. 
     *
     * @param   nm    property name.
     * @param   val   default value.
     * @return  the <code>Long</code> value of the property.
     * @see     java.lang.System#getProperty(java.lang.String)
     * @see     java.lang.System#getProperty(java.lang.String, java.lang.String)
     * @since   JDK1.0
     */
    public static Long getLong(String nm, long val) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null)
	    sm.checkPropertyAccess(nm);
        Long result = Long.getLong(nm, null);
        return (result == null) ? new Long(val) : result;
    }

    /**
     * Determines the <code>long</code> value of the system property 
     * with the specified name. 
     * <p>
     * The first argument is treated as the name of a system property. 
     * System properties are accessible through <code>getProperty</code>  
     * and , a method defined by the <code>System</code> class. The 
     * string value of this property is then interpreted as a long value 
     * and a <code>Long</code> object representing this value is returned. 
     * <p>
     * If the property value begins with "<code>0x</code>" or 
     * "<code>#</code>", not followed by a minus sign, the rest 
     * of it is parsed as a hexadecimal integer exactly as for the method 
     * <code>Long.valueOf</code> with radix 16. 
     * <p>
     * If the property value begins with "<code>0</code>", 
     * then it is parsed as an octal integer exactly as for the method 
     * <code>Long.valueOf</code> with radix 8. 
     * <p>
     * Otherwise the property value is parsed as a decimal integer 
     * exactly as for the method <code>Long.valueOf</code> with radix 10. 
     * <p>
     * Note that, in every case, neither <code>L</code> nor 
     * <code>l</code> is permitted to appear at the end of the string. 
     * <p>
     * The second argument is the default value. If there is no property 
     * of the specified name, or if the property does not have the 
     * correct numeric format, then the second argument is returned. 
     *
     * @param   nm    the property name.
     * @param   val   the default <code>Long</code> value.
     * @return  the <code>long</code> value of the property.
     * @see     java.lang.Long#valueOf(java.lang.String, int)
     * @see     java.lang.System#getProperty(java.lang.String)
     * @see     java.lang.System#getProperty(java.lang.String, java.lang.String)
     * @since   JDK1.0
     */
    public static Long getLong(String nm, Long val) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null)
	    sm.checkPropertyAccess(nm);
	String v = System.getProperty(nm);
	if (v != null) {
	    try {
		if (v.startsWith("0x")) {
		    return Long.valueOf(v.substring(2), 16);
		}
		if (v.startsWith("#")) {
		    return Long.valueOf(v.substring(1), 16);
		}
		if (v.startsWith("0") && v.length() > 1) {
		    return Long.valueOf(v.substring(1), 8);
		}
		return Long.valueOf(v);
	    } catch (NumberFormatException e) {
	    }
	}	
	return val;
    }

    /** use serialVersionUID from JDK 1.0.2 for interoperability */
    private static final long serialVersionUID = 4290774380558885855L;
}