TestRandomBigInteger.java

package org.bouncycastle.util.test;

import org.bouncycastle.util.BigIntegers;

/**
 * A fixed secure random designed to return data for someone needing to create a single BigInteger.
 */
public class TestRandomBigInteger
    extends FixedSecureRandom
{
    /**
     * Constructor from a base 10 represention of a BigInteger.
     *
     * @param encoding a base 10 represention of a BigInteger.
     */
    public TestRandomBigInteger(String encoding)
    {
        this(encoding, 10);
    }

    /**
     * Constructor from a base radix represention of a BigInteger.
     *
     * @param encoding a String BigInteger of base radix.
     * @param radix the radix to use.
     */
    public TestRandomBigInteger(String encoding, int radix)
    {
        super(new FixedSecureRandom.Source[] { new FixedSecureRandom.BigInteger(BigIntegers.asUnsignedByteArray(new java.math.BigInteger(encoding, radix))) });
    }

    /**
     * Constructor based on a byte array.
     *
     * @param encoding a 2's complement representation of the BigInteger.
     */
    public TestRandomBigInteger(byte[] encoding)
    {
        super(new FixedSecureRandom.Source[] { new FixedSecureRandom.BigInteger(encoding) });
    }

    /**
     * Constructor which ensures encoding will produce a BigInteger from a request from the passed in bitLength.
     *
     * @param bitLength bit length for the BigInteger data request.
     * @param encoding bytes making up the encoding.
     */
    public TestRandomBigInteger(int bitLength, byte[] encoding)
    {
        super(new FixedSecureRandom.Source[] { new FixedSecureRandom.BigInteger(bitLength, encoding) });
    }
}