Exclusion rules

Exclusion rules tell HashGuard what to leave alone. They live in the exclude key of the configuration, as a single string with one rule per line:

{
  "exclude": "com.example.api.**\nflatten:com.example.render.**\nrename:com.example.Main**"
}

Use them for code you cannot annotate, such as generated code or classes reached by name from configuration files. In your own code, annotations are usually clearer.

Rule format

[<token>:][!]<pattern>

Part	Meaning
<token>:	Optional. Limits the rule to one transformer, using its token, for example flatten: or rename:. global: or no prefix applies the rule to every transformer.
!	Optional. Turns the rule into a re-inclusion: what it matches is protected again, even inside a broader exclusion.
<pattern>	The class, method or field to match, with dots as separators.

Empty lines and lines starting with # are ignored.

Patterns

Patterns are matched against names written with dots:

Subject	Written as
A class	com.example.Main
A method	com.example.Main.run()
A field	com.example.Main.config

Nested classes follow their outer class: a rule on com.example.Main also covers Main$Inner.

Pattern	Matches
com.example.Main	Exactly that name.
com.example.*	Names that start with com.example. at the same depth: the classes of the package, not its sub-packages.
com.example.**	Everything under com.example, at any depth.
com.example.Main**	The class and all of its members.
*Test or **Test	Names that end with Test.

Examples

Keep a public API readable, but still encrypt its strings:

rename:com.example.api.**

Leave a package out of everything, except one class:

com.example.legacy.**
!com.example.legacy.LicenceCheck

Keep the hot rendering code out of the expensive control-flow passes only:

flatten:com.example.render.**
controlFlow:com.example.render.**

Exclude a method that is called through reflection:

rename:com.example.plugins.Loader.load()

How rules combine

• A subject is excluded from a transformer when at least one rule for that transformer, or a global rule, matches it.
• A matching re-inclusion (!) always wins over exclusions, wherever it sits in the list.
• Rules are evaluated against the original names, so they keep working after renaming.