Software reengineering in Software Engineering - Step-by-Step Execution

Concept Flow - Software reengineering

Identify Old Software

↓

Analyze Current System

↓

Plan Reengineering Approach

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Reverse Engineering

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Restructuring / Redocumentation

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Forward Engineering / Redevelopment

↓

Testing & Validation

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Deploy Updated Software

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End

This flow shows the main steps in software reengineering from identifying old software to deploying the updated version.

Execution Sample

Software Engineering

1. Identify old software needing improvement
2. Analyze its structure and problems
3. Plan how to improve or rewrite parts
4. Extract design info (reverse engineering)
5. Restructure or rewrite code
6. Test and deploy improved software

This sequence outlines the key actions taken during software reengineering.

Analysis Table

Step	Action	Purpose	Result
1	Identify old software	Find software needing update	Software selected for reengineering
2	Analyze current system	Understand existing design and issues	Documentation of current state
3	Plan reengineering approach	Decide what to improve and how	Reengineering strategy created
4	Reverse engineering	Extract design and requirements	Design models and documentation produced
5	Restructuring / Redocumentation	Improve code structure without changing behavior	Cleaner, easier to maintain code
6	Forward engineering / Redevelopment	Rewrite or add new features	Updated or new software components
7	Testing & Validation	Ensure software works correctly	Verified software ready for use
8	Deploy updated software	Release improved software to users	Software in production
9	End	Process complete	Software reengineering finished

💡 All steps completed, software is improved and deployed

State Tracker

Variable	Start	After Step 2	After Step 4	After Step 6	Final
Software State	Old and problematic	Analyzed and documented	Design extracted	Code restructured and rewritten	Tested and deployed

Key Insights - 3 Insights

Why do we do reverse engineering before rewriting code?

Reverse engineering helps us understand the existing software design and requirements (see execution_table step 4), so we can plan improvements accurately.

Is restructuring the same as rewriting the software?

No, restructuring improves the internal code structure without changing behavior (step 5), while rewriting (forward engineering) may add or change features (step 6).

Why is testing important after reengineering?

Testing (step 7) ensures that the improved software works correctly and meets requirements before deployment, preventing new errors.

Visual Quiz - 3 Questions

Look at the execution_table, what is the result after step 4 (Reverse engineering)?

A Software deployed to users

B Design models and documentation produced

C Code rewritten with new features

D Old software identified

💡 Hint

Check the 'Result' column for step 4 in the execution_table

At which step does the software get tested and validated?

A Step 7

B Step 5

C Step 3

D Step 2

💡 Hint

Look for 'Testing & Validation' in the 'Action' column of the execution_table

If we skip restructuring, which step would be missing from the execution_table?

A Step 6

B Step 4

C Step 5

D Step 7

💡 Hint

Restructuring is described in step 5 under 'Action' in the execution_table

Concept Snapshot

Software reengineering improves old software by analyzing, restructuring, and rewriting it.
Key steps: Identify, Analyze, Reverse engineer, Restructure, Redevelop, Test, Deploy.
Reverse engineering extracts design info.
Restructuring cleans code without changing behavior.
Testing ensures quality before release.

Full Transcript

Software reengineering is the process of improving existing software by first identifying the software that needs improvement, then analyzing its current structure and problems. Next, a plan is made on how to improve or rewrite parts of the software. Reverse engineering is used to extract design and requirement information from the existing software. After that, restructuring or redocumentation improves the code structure without changing its behavior. Forward engineering or redevelopment rewrites or adds new features. Testing and validation ensure the software works correctly. Finally, the updated software is deployed to users. This process helps keep software useful and maintainable over time.