Code analysis is the deliberate investigation of source code and runtime behavior to understand what an application does, identify differences from expected behavior, resolve problems, and support changes. It combines observation, logic, and selective exploration rather than guesswork. section 1.0
Effective analysis moves between the visible execution path and the instructions hidden behind method calls. Method names may be insufficient evidence, so each deeper jump should answer a specific question while avoiding unnecessary cognitive complexity. section 2.1
Use these questions to guide an investigation:
- What does each instruction do, and what behavior does it hide behind a method call? section 2.1
- What should the system do, what does it actually do, and where do those behaviors diverge? section 1.0
- Which details require deeper inspection, and which can be skipped to keep the investigation manageable? section 2.1
Listing 2.1 An example of a method to debug
public class Decoder {
public Integer decode(List<String> input) {
int total = 0;
for (String s : input) {
var digits = new StringDigitExtractor(s).extractDigits();
total += digits.stream().collect(Collectors.summingInt(i -> i));
}
return total;
}
}
Inspect the Decoder method by following the input loop, the StringDigitExtractor call, digit collection, and accumulated result; then investigate hidden behavior where needed. section 2.1
