/*
* Copyright 2007-2013 UnboundID Corp.
* All Rights Reserved.
*/
/*
* Copyright (C) 2008-2013 UnboundID Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (GPLv2 only)
* or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses>.
*/
package com.hwlcn.ldap.asn1;
import com.hwlcn.core.annotation.NotMutable;
import com.hwlcn.core.annotation.ThreadSafety;
import com.hwlcn.ldap.util.ThreadSafetyLevel;
import static com.hwlcn.ldap.asn1.ASN1Constants.*;
import static com.hwlcn.ldap.asn1.ASN1Messages.*;
import static com.hwlcn.ldap.util.Debug.*;
/**
* This class provides an ASN.1 integer element, whose value may be represented
* as an integer with up to a 32-bit representation.
*/
@NotMutable()
@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
public final class ASN1Integer
extends ASN1Element
{
/**
* The serial version UID for this serializable class.
*/
private static final long serialVersionUID = -733929804601994372L;
// The int value for this element.
private final int intValue;
/**
* Creates a new ASN.1 integer element with the default BER type and the
* provided int value.
*
* @param intValue The int value to use for this element.
*/
public ASN1Integer(final int intValue)
{
super(UNIVERSAL_INTEGER_TYPE, encodeIntValue(intValue));
this.intValue = intValue;
}
/**
* Creates a new ASN.1 integer element with the specified BER type and the
* provided int value.
*
* @param type The BER type to use for this element.
* @param intValue The int value to use for this element.
*/
public ASN1Integer(final byte type, final int intValue)
{
super(type, encodeIntValue(intValue));
this.intValue = intValue;
}
/**
* Creates a new ASN.1 integer element with the specified BER type and the
* provided int and pre-encoded values.
*
* @param type The BER type to use for this element.
* @param intValue The int value to use for this element.
* @param value The pre-encoded value to use for this element.
*/
private ASN1Integer(final byte type, final int intValue, final byte[] value)
{
super(type, value);
this.intValue = intValue;
}
/**
* Encodes the provided int value to a byte array suitable for use as the
* value of an integer element.
*
* @param intValue The int value to be encoded.
*
* @return A byte array containing the encoded value.
*/
static byte[] encodeIntValue(final int intValue)
{
if (intValue < 0)
{
if ((intValue & 0xFFFFFF80) == 0xFFFFFF80)
{
return new byte[]
{
(byte) (intValue & 0xFF)
};
}
else if ((intValue & 0xFFFF8000) == 0xFFFF8000)
{
return new byte[]
{
(byte) ((intValue >> 8) & 0xFF),
(byte) (intValue & 0xFF)
};
}
else if ((intValue & 0xFF800000) == 0xFF800000)
{
return new byte[]
{
(byte) ((intValue >> 16) & 0xFF),
(byte) ((intValue >> 8) & 0xFF),
(byte) (intValue & 0xFF)
};
}
else
{
return new byte[]
{
(byte) ((intValue >> 24) & 0xFF),
(byte) ((intValue >> 16) & 0xFF),
(byte) ((intValue >> 8) & 0xFF),
(byte) (intValue & 0xFF)
};
}
}
else
{
if ((intValue & 0x0000007F) == intValue)
{
return new byte[]
{
(byte) (intValue & 0x7F)
};
}
else if ((intValue & 0x00007FFF) == intValue)
{
return new byte[]
{
(byte) ((intValue >> 8) & 0x7F),
(byte) (intValue & 0xFF)
};
}
else if ((intValue & 0x007FFFFF) == intValue)
{
return new byte[]
{
(byte) ((intValue >> 16) & 0x7F),
(byte) ((intValue >> 8) & 0xFF),
(byte) (intValue & 0xFF)
};
}
else
{
return new byte[]
{
(byte) ((intValue >> 24) & 0x7F),
(byte) ((intValue >> 16) & 0xFF),
(byte) ((intValue >> 8) & 0xFF),
(byte) (intValue & 0xFF)
};
}
}
}
/**
* Retrieves the int value for this element.
*
* @return The int value for this element.
*/
public int intValue()
{
return intValue;
}
/**
* Decodes the contents of the provided byte array as an integer element.
*
* @param elementBytes The byte array to decode as an ASN.1 integer element.
*
* @return The decoded ASN.1 integer element.
*
* @throws ASN1Exception If the provided array cannot be decoded as an
* integer element.
*/
public static ASN1Integer decodeAsInteger(final byte[] elementBytes)
throws ASN1Exception
{
try
{
int valueStartPos = 2;
int length = (elementBytes[1] & 0x7F);
if (length != elementBytes[1])
{
final int numLengthBytes = length;
length = 0;
for (int i=0; i < numLengthBytes; i++)
{
length <<= 8;
length |= (elementBytes[valueStartPos++] & 0xFF);
}
}
if ((elementBytes.length - valueStartPos) != length)
{
throw new ASN1Exception(ERR_ELEMENT_LENGTH_MISMATCH.get(length,
(elementBytes.length - valueStartPos)));
}
final byte[] value = new byte[length];
System.arraycopy(elementBytes, valueStartPos, value, 0, length);
int intValue;
switch (value.length)
{
case 1:
intValue = (value[0] & 0xFF);
if ((value[0] & 0x80) != 0x00)
{
intValue |= 0xFFFFFF00;
}
break;
case 2:
intValue = ((value[0] & 0xFF) << 8) | (value[1] & 0xFF);
if ((value[0] & 0x80) != 0x00)
{
intValue |= 0xFFFF0000;
}
break;
case 3:
intValue = ((value[0] & 0xFF) << 16) | ((value[1] & 0xFF) << 8) |
(value[2] & 0xFF);
if ((value[0] & 0x80) != 0x00)
{
intValue |= 0xFF000000;
}
break;
case 4:
intValue = ((value[0] & 0xFF) << 24) | ((value[1] & 0xFF) << 16) |
((value[2] & 0xFF) << 8) | (value[3] & 0xFF);
break;
default:
throw new ASN1Exception(ERR_ENUMERATED_INVALID_LENGTH.get(
value.length));
}
return new ASN1Integer(elementBytes[0], intValue, value);
}
catch (final ASN1Exception ae)
{
debugException(ae);
throw ae;
}
catch (final Exception e)
{
debugException(e);
throw new ASN1Exception(ERR_ELEMENT_DECODE_EXCEPTION.get(e), e);
}
}
/**
* Decodes the provided ASN.1 element as an integer element.
*
* @param element The ASN.1 element to be decoded.
*
* @return The decoded ASN.1 integer element.
*
* @throws ASN1Exception If the provided element cannot be decoded as an
* integer element.
*/
public static ASN1Integer decodeAsInteger(final ASN1Element element)
throws ASN1Exception
{
int intValue;
final byte[] value = element.getValue();
switch (value.length)
{
case 1:
intValue = (value[0] & 0xFF);
if ((value[0] & 0x80) != 0x00)
{
intValue |= 0xFFFFFF00;
}
break;
case 2:
intValue = ((value[0] & 0xFF) << 8) | (value[1] & 0xFF);
if ((value[0] & 0x80) != 0x00)
{
intValue |= 0xFFFF0000;
}
break;
case 3:
intValue = ((value[0] & 0xFF) << 16) | ((value[1] & 0xFF) << 8) |
(value[2] & 0xFF);
if ((value[0] & 0x80) != 0x00)
{
intValue |= 0xFF000000;
}
break;
case 4:
intValue = ((value[0] & 0xFF) << 24) | ((value[1] & 0xFF) << 16) |
((value[2] & 0xFF) << 8) | (value[3] & 0xFF);
break;
default:
throw new ASN1Exception(ERR_INTEGER_INVALID_LENGTH.get(value.length));
}
return new ASN1Integer(element.getType(), intValue, value);
}
/**
* Appends a string representation of this ASN.1 element to the provided
* buffer.
*
* @param buffer The buffer to which to append the information.
*/
@Override()
public void toString(final StringBuilder buffer)
{
buffer.append(intValue);
}
}