org.apache.harmony.security.asn1.ASN1Integer Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @author Vladimir N. Molotkov, Stepan M. Mishura
* @version $Revision$
*/
package org.apache.harmony.security.asn1;
import java.io.IOException;
import java.math.BigInteger;
/**
* This class represents ASN.1 Integer type.
*
* @see ASN.1
*/
public final class ASN1Integer extends ASN1Primitive {
/** default implementation */
private static final ASN1Integer ASN1 = new ASN1Integer();
/**
* Constructs ASN.1 Integer type
*
* The constructor is provided for inheritance purposes
* when there is a need to create a custom ASN.1 Integer type.
* To get a default implementation it is recommended to use
* getInstance() method.
*/
public ASN1Integer() {
super(TAG_INTEGER);
}
/**
* Returns ASN.1 Integer type default implementation
*
* The default implementation works with encoding
* that is represented as byte array in two's-complement notation.
*
* @return ASN.1 Integer type default implementation
*/
public static ASN1Integer getInstance() {
return ASN1;
}
public Object decode(BerInputStream in) throws IOException {
in.readInteger();
if (in.isVerify) {
return null;
}
return getDecodedObject(in);
}
/**
* Extracts array of bytes from BER input stream.
*
* @return array of bytes
*/
public Object getDecodedObject(BerInputStream in) throws IOException {
byte[] bytesEncoded = new byte[in.length];
System.arraycopy(in.buffer, in.contentOffset, bytesEncoded, 0,
in.length);
return bytesEncoded;
}
public void encodeContent(BerOutputStream out) {
out.encodeInteger();
}
public void setEncodingContent(BerOutputStream out) {
out.length = ((byte[]) out.content).length;
}
/**
* Converts decoded ASN.1 Integer to int value.
* If the object represents an integer value
* larger than 32 bits, the high bits will be lost.
*
* @param decoded a decoded object corresponding to this type
* @return decoded int value.
*/
public static int toIntValue(Object decoded) {
return new BigInteger((byte[]) decoded).intValue();
}
/**
* Converts decoded ASN.1 Integer to a BigInteger.
*
* @param decoded a decoded object corresponding to this type
* @return decoded BigInteger value.
*/
public static BigInteger toBigIntegerValue(Object decoded) {
return new BigInteger((byte[]) decoded);
}
/**
* Converts primitive int value to a form most suitable for encoding.
*
* @param value primitive value to be encoded
* @return object suitable for encoding
*/
public static Object fromIntValue(int value) {
return BigInteger.valueOf(value).toByteArray();
}
}