Q: Why does Clover use source code instrumentation?

Source code instrumentation is the most powerful, flexible and accurate way to provide code coverage analysis.

The following table compares different methods of obtaining code coverage and their relative benefits:

Possible feature

JVMDI/PI

Bytecode instrumentation

Source code instrumentation

Gathers method coverage

はい

はい

はい

Gathers statement coverage

line only

indirectly

はい

Gathers branch coverage

indirectly

indirectly

はい

Can work without source

はい

はい

いいえ

Requires separate build

いいえ

いいえ

はい

Requires specialised runtime

はい

はい

いいえ

Gathers source metrics

いいえ

いいえ

はい

View coverage data inline with source

not accurate

not accurate

はい

Source level directives to control coverage gathering

いいえ

いいえ

はい

Control which entities are reported on

limited

limited

はい

Compilation time

no impact

変数

変数

Runtime performace

high impact

変数

変数

Container friendly

いいえ

いいえ

はい