asn1bitstring.java

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/******************************************************************************
 *
 * Copyright (c) 1999-2003 AppGate Network Security AB. All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code as
 * defined in and that are subject to the MindTerm Public Source License,
 * Version 2.0, (the 'License'). You may not use this file except in compliance
 * with the License.
 * 
 * You should have received a copy of the MindTerm Public Source License
 * along with this software; see the file LICENSE.  If not, write to
 * AppGate Network Security AB, Otterhallegatan 2, SE-41118 Goteborg, SWEDEN
 *
 *****************************************************************************/

package com.mindbright.asn1;


public class ASN1BitString extends ASN1String {

    public ASN1BitString() {
	super(ASN1.TAG_BITSTRING);
    }

    public int getBitCount() {
	return ((value.length - 1) * 8) - value[0];
    }

    public byte[] getBitArray() {
	byte[] ba = new byte[value.length - 1];
	System.arraycopy(value, 1, ba, 0, ba.length);
	return ba;
    }

    public void setBitArray(byte[] bitArray, int off, int bitCount) {
	int    unusedBits = (8 - (bitCount % 8)) % 8;
	int    byteCount  = ((bitCount / 8) + 1);
	byte[] derEnc     = new byte[byteCount + 1];

	derEnc[0] = (byte)unusedBits;
	System.arraycopy(bitArray, off, derEnc, 1, byteCount);

	setRaw(derEnc);
    }

    public boolean[] getBooleanArray() {
	int       bitCount = ((value.length - 1) * 8) - value[0];
	boolean[] bits     = new boolean[bitCount];

	for(int i = 0; i < bitCount; i++) {
	    int m = 0x80 >>> (i % 8);
	    bits[i] = ((((int)value[(i / 8) + 1] & 0xff) & m) == m);
	}

	return bits;
    }

    public void setBooleanArray(boolean[] bits) {
	int    bitCount   = bits.length;
	int    unusedBits = (8 - (bitCount % 8)) % 8;
	int    byteCount  = ((bitCount / 8) + 1);
	byte[] derEnc     = new byte[byteCount + 1];

	derEnc[0] = (byte)unusedBits;
	for(int i = 0; i < bitCount; i++) {
	    int m = 0x80 >>> (i % 8);
	    derEnc[(i / 8) + 1] |= (bits[i] ? m : 0x00);
	}
	setRaw(derEnc);
    }

    public String toPrintableString() {
        for (int i=0; i<value.length; i++) {
            if (value[i] < 10 || value[i] > 127)
                return "0x" + com.mindbright.util.HexDump.toString(value);
        }
        return new String(value);
    }
}