http://www.bouncycastle.org/java.html: The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.8.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.util.test;

import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;


This is a testing utility class to check the property that an OutputStream is never closed in some particular context - typically when wrapped by another OutputStream that should not be forwarding its OutputStream.close() calls. Not needed in production code. 
/**
 * This is a testing utility class to check the property that an {@link OutputStream} is never
 * closed in some particular context - typically when wrapped by another {@link OutputStream} that
 * should not be forwarding its {@link OutputStream#close()} calls. Not needed in production code.
 */
public class UncloseableOutputStream extends FilterOutputStream
{
    public UncloseableOutputStream(OutputStream s)
    {
        super(s);
    }

    public void close()
    {
        throw new RuntimeException("close() called on UncloseableOutputStream");
    }

    public void write(byte[] b, int off, int len) throws IOException
    {
        out.write(b, off, len);
    }
 }