derbitstring.java

来自「《移动Agent技术》一书的所有章节源代码。」· Java 代码 · 共 86 行

package org.bouncycastle.asn1;

import java.io.*;

public class DERBitString
    extends DERObject
{
    protected byte[]      data;
    protected int         padBits;

    protected DERBitString(
        byte    data,
        int     padBits)
    {
        this.data = new byte[1];
        this.data[0] = data;
        this.padBits = padBits;
    }

    /**
     * @param data the octets making up the bit string.
     * @param padBits the number of extra bits at the end of the string.
     */
    public DERBitString(
        byte[]  data,
        int     padBits)
    {
        this.data = data;
        this.padBits = padBits;
    }

    public DERBitString(
        byte[]  data)
    {
        this(data, 0);
    }

    public DERBitString(
        DERObject  obj)
    {
        try
        {
            ByteArrayOutputStream   bOut = new ByteArrayOutputStream();
            DEROutputStream         dOut = new DEROutputStream(bOut);

            dOut.writeObject(obj);
            dOut.close();

            this.data = bOut.toByteArray();
            this.padBits = 0;
        }
        catch (IOException e)
        {
            throw new IllegalArgumentException("Error processing object : " + e.toString());
        }
    }

    public DERBitString(
        DEREncodable  obj)
    {
        this(obj.getDERObject());
    }

    public byte[] getBytes()
    {
        return data;
    }

    public int getPadBits()
    {
        return padBits;
    }

    void encode(
        DEROutputStream  out)
        throws IOException
    {
        byte[]  bytes = new byte[getBytes().length + 1];

        bytes[0] = (byte)getPadBits();
        System.arraycopy(getBytes(), 0, bytes, 1, bytes.length - 1);

        out.writeEncoded(BIT_STRING, bytes);
    }
}