Home > Articles > Programming

New Debugging Paradigms for Object-Based Software Development

Methodologies for program construction have matured over the last 25 years. Debugging technology has not kept pace with programming technology in that we essentially debug using the same paradigms of 25 years ago. The advent of low-cost multimedia output makes it possible to provide more than one human sensory channel with input to aid the debugging process. Author Ron Reeves explains why this channel is important, why this would be a significant advance in debugging, why it is well-suited for object-based systems, and suggests that future tooling begin to exploit the full range of the human sensory input system.
Like this article? We recommend

Like this article? We recommend

The object methodology is one of the first major shifts in software development in the last 25 years. The creation of objects, where an object represents a functionally intelligent grouping of state and operations whose details can be concealed, gives the software developer a higher metalevel upon which to base a solution creation. Object methodology, as currently practiced, is the culmination of the information-hiding methodology proposed by Parnas and refined through decades of practical use.

In the last couple of decades, the paradigm of Object Methodology has hit the mainstream computing market; it is no longer an arcane art practiced by academics or megaline-system developers, but instead is readily available to even all programmers. Object implementations such as the Microsoft .NET Framework has made the technology pervasive.

The availability of object methodology has allowed us to design and construct software systems far more complex than we could have imagined even a decade ago. One of the problems that have arisen, however, is the very abstraction we use to create these complex systems can not only mask their complexity during development, but can mask their complexity during debugging and post-deployment maintenance. The original programmers can often translate their mental models of objects into code, but the maintainers–in fact, even the programmers themselves mere months later–must "reverse engineer" these structures back into a mental model.

Debugging Versus Browsing

Debugging, in contrast to the sophistication of our construction techniques, has remained largely unchanged over the same period of time. We have very few debugging tools that are object-modeled, at least in the mainstream computing world. Instead, we still set breakpoints, use debug-print statements, and display the contents of memory locations in an attempt to figure out what has gone wrong.

It is important here that we want to contrast debuggers with browsers. A browser allows us to inspect code, study module relationships, display call graphs, and generally inspect the static representation of a program. There have been some quite nice browsing environments developed, both independent of, and as integrated components of, compilation systems. However, by our definition, a debugger is a tool that allows us to inspect, in some way, the dynamic behavior of a program as it is executing.

Debugging is often an exercise in "reverse engineering." We must deduce, from the current program state and current execution point, how the current state and execution point were reached, and why, and what can be done to correct them if the state or execution point (or both) are incorrect.

Reverse engineering is also known as design recovery. However, the people practicing "design recovery" are often working at a much higher structural level than is useful for debugging. Or, to hearken back to an issue of the 1970s, design recovery is working at the "design-in-the-large" level and debugging is working at the "design-in-the-small" level.

The problem in both cases, however, is quite similar: reconstruct a model of the program that can be understood by the reader. In many cases we find the design-recovery-in-the-large uses visual notation — for example, E-R diagrams, Dean-Cordy diagrams [DC95], UML, and so on. For decades (and, in some more regressive contexts, even today) flowcharts are used to describe code at the statement level. These representations have much in common in terms of human perception; they involve a sensory channel capable of handling vast amounts of information: the visual system.

The cost of computers, and the cost of specialized peripherals, for decades limited us in how we could interact with the computer. We debugged by lights-and-switches, core dumps, octal or hexadecimal displays of individual words or bytes, and so on. The limited bandwidth with which we could interact with the computer was a significant barrier in the understanding of the software systems we were trying to debug.

Today, the balance has changed. High-resolution full-color bitmap displays mean that we can often animate our algorithms in a graphical fashion. The cost of interaction is negligible compared to the cost of development overall. Computers are, for practical purposes, nearly free compared to the people who use them. Thus we can get graphical displays of our data structures, chase down complex pointer chains with a series of mouse clicks, see our data in an almost-readable form, and even watch algorithms in action.

But what’s missing from this picture? It turns out that our new tools still only show us pieces of the algorithm, often in terms of the computer’s representation, not our mental model. And while we are utilizing the visual channel to a higher degree, we have virtually neglected another significant human input channel, the auditory system. Thus, we want to approach the problem of debugging from two viewpoints: a better presentation of visual information, and use of the human auditory channel as a means of enhancing our ability to both build our cognitive model and interpret the program’s behavior in terms of that cognitive model.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020