#vulnerable code 
                                public void handle(final HttpRequest request, 
                       final HttpResponse response,
                       final HttpContext context)
        throws HttpException, IOException {

        String method = request.getRequestLine().getMethod().toUpperCase();
        if (!"GET".equals(method) &&
            !"POST".equals(method) &&
            !"PUT".equals(method)
            ) {
            throw new MethodNotSupportedException
                (method + " not supported by " + getClass().getName());
        }

        HttpEntity entity = null;
        if (request instanceof HttpEntityEnclosingRequest)
            entity = ((HttpEntityEnclosingRequest)request).getEntity();

        // For some reason, just putting the incoming entity into
        // the response will not work. We have to buffer the message.
        byte[] data = null;
        if (entity == null) {
            data = new byte [0];
        } else {
            data = EntityUtils.toByteArray(entity);
        }

        ByteArrayEntity bae = new ByteArrayEntity(data);
        bae.setContentType(entity.getContentType());
        entity = bae;

        response.setStatusCode(HttpStatus.SC_OK);
        response.setEntity(entity);

    } 
                            #location 29 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                public void handle(final HttpRequest request, 
                       final HttpResponse response,
                       final HttpContext context)
        throws HttpException, IOException {

        String method = request.getRequestLine().getMethod().toUpperCase();
        if (!"GET".equals(method) &&
            !"POST".equals(method) &&
            !"PUT".equals(method)
            ) {
            throw new MethodNotSupportedException
                (method + " not supported by " + getClass().getName());
        }

        HttpEntity entity = null;
        if (request instanceof HttpEntityEnclosingRequest)
            entity = ((HttpEntityEnclosingRequest)request).getEntity();

        // For some reason, just putting the incoming entity into
        // the response will not work. We have to buffer the message.
        byte[] data = null;
        if (entity == null) {
            data = new byte [0];
        } else {
            data = EntityUtils.toByteArray(entity);
        }

        ByteArrayEntity bae = new ByteArrayEntity(data);
        if (entity != null) {
            bae.setContentType(entity.getContentType());
        }
        entity = bae;

        response.setStatusCode(HttpStatus.SC_OK);
        response.setEntity(entity);

    }