integer.java

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		    throw new NumberFormatException(s);
		}
		if (result < multmin) {
		    throw new NumberFormatException(s);
		}
		result *= radix;
		if (result < limit + digit) {
		    throw new NumberFormatException(s);
		}
		result -= digit;
	    }
	} else {
	    throw new NumberFormatException(s);
	}
	if (negative) {
	    if (i > 1) {
		return result;
	    } else {	/* Only got "-" */
		throw new NumberFormatException(s);
	    }
	} else {
	    return -result;
	}
    }

    /**
     * Parses the string argument as a signed decimal integer. The 
     * characters in the string must all be decimal digits, except that 
     * the first character may be an ASCII minus sign <code>'-'</code> to 
     * indicate a negative value. 
     *
     * @param      s   a string.
     * @return     the integer represented by the argument in decimal.
     * @exception  NumberFormatException  if the string does not contain a
     *               parsable integer.
     * @since      JDK1.0
     */
    public static int parseInt(String s) throws NumberFormatException {
	return parseInt(s,10);
    }

    /**
     * Returns a new Integer object initialized to the value of the
     * specified String.  Throws an exception if the String cannot be
     * parsed as an int.
     *
     * @param      s   the string to be parsed.
     * @return     a newly constructed <code>Integer</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 integer.
     * @since   JDK1.0
     */
    public static Integer valueOf(String s, int radix) throws NumberFormatException {
	return new Integer(parseInt(s,radix));
    }

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

    /**
     * The value of the Integer.
     */
    private int value;

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

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

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

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

    /**
     * Returns the value of this Integer as an int.
     *
     * @return  the <code>int</code> value represented by this object.
     * @since   JDK1.0
     */
    public int intValue() {
	return value;
    }

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

    /**
     * Returns the value of this Integer as a float.
     *
     * @return  the <code>int</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 Integer as a double.
     *
     * @return  the <code>int</code> value represented by this object 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 Integer's value.
     *
     * @return  a string representation of the value of this object in
     *          base&nbsp;10.
     * @since   JDK1.0
     */
    public String toString() {
	return String.valueOf(value);
    }

    /**
     * Returns a hashcode for this Integer.
     *
     * @return  a hash code value for this object. 
     * @since   JDK1.0
     */
    public int hashCode() {
	return value;
    }

    /**
     * Compares this object to the specified object.
     * The result is <code>true</code> if and only if the argument is not 
     * <code>null</code> and is an <code>Integer</code> object that contains 
     * the same <code>int</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 Integer)) {
	    return value == ((Integer)obj).intValue();
	}
	return false;
    }

    /**
     * Determines the integer 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 an integer 
     * value and an <code>Integer</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>Integer</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 Integer getInteger(String nm) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null)
	    sm.checkPropertyAccess(nm);
	return getInteger(nm, null);
    }

    /**
     * Determines the integer 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 an integer 
     * value and an <code>Integer</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 an 
     * <code>Integer</code> object that represents the value of the 
     * second argument is returned. 
     *
     * @param   nm   property name.
     * @param   val   default value.
     * @return  the <code>Integer</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 Integer getInteger(String nm, int val) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null)
	    sm.checkPropertyAccess(nm);
        Integer result = getInteger(nm, null);
        return (result == null) ? new Integer(val) : result;
    }

    /**
     * Determines the integer 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 an integer 
     * value and an <code>Integer</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>Integer.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>Integer.valueOf</code> with radix 8. 
     * <p>
     * Otherwise the property value is parsed as a decimal integer 
     * exactly as for the method <code>Integer.valueOf</code> with radix 10.
     * <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   property name.
     * @param   val   default value.
     * @return  the <code>Integer</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 Integer getInteger(String nm, Integer val) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null)
	    sm.checkPropertyAccess(nm);
	String v = System.getProperty(nm);
	if (v != null) {
	    try {
		return Integer.decode(v);
	    } catch (NumberFormatException e) {
	    }
	}	
	return val;
    }

    /**
     * Decodes a string into an Integer. Deals with decimal, hexadecimal,
     * and octal numbers.
     * @param nm the string to decode
     * @since   JDK1.1
     */
    public static Integer decode(String nm) throws NumberFormatException {
	if (nm.startsWith("0x")) {
	    return Integer.valueOf(nm.substring(2), 16);
	}
	if (nm.startsWith("#")) {
	    return Integer.valueOf(nm.substring(1), 16);
	}
	if (nm.startsWith("0") && nm.length() > 1) {
	    return Integer.valueOf(nm.substring(1), 8);
	}
	
	return Integer.valueOf(nm);
    }

    /** use serialVersionUID from JDK 1.0.2 for interoperability */
    private static final long serialVersionUID = 1360826667806852920L;
}