test(java): add regression test for MD5 detection in JCA MessageDigest

[sachin9058]

MD5 detection is already supported by the JCA MessageDigest matcher but was not covered by tests.

This PR adds a regression test to ensure MD5 detection remains stable and to prevent accidental regressions in future changes.

Changes

• Added test fixture:
  java/src/test/files/rules/detection/jca/digest/JcaMessageDigestGetInstanceMd5TestFile.java

• Added regression test:
  java/src/test/java/com/ibm/plugin/rules/detection/jca/digest/JcaMessageDigestGetInstanceMd5Test.java

• Verified detection output:

  • Algorithm: MD5
  • DigestSize: 128
  • BlockSize: 512

Validation

• Ran targeted test:
  mvn -pl java -am -Dtest=JcaMessageDigestGetInstanceMd5Test test

• Built plugin successfully:
  mvn clean install

• Verified runtime behavior via SonarQube scan (CBOM generation)

Notes

• No changes to detection logic were required.
• This PR strictly improves test coverage.

Happy to extend coverage to additional algorithms (e.g., SHA-1, SHA-512) if needed.

[Copilot]

Pull request overview

Adds a Java regression test to lock in existing MD5 detection behavior for java.security.MessageDigest#getInstance(...) in the Sonar Cryptography Plugin’s JCA digest matcher, improving coverage without changing detection logic.

Changes:

• Added a new test fixture exercising MessageDigest.getInstance("MD5") with an expected “Noncompliant” issue.
• Added a new JUnit test validating the detection store value (Algorithm=MD5) and the translated node details (digest, digest size 128, block size 512).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
java/src/test/java/com/ibm/plugin/rules/detection/jca/digest/JcaMessageDigestGetInstanceMd5Test.java	New JUnit regression test asserting MD5 detection and translated node properties.
java/src/test/files/rules/detection/jca/digest/JcaMessageDigestGetInstanceMd5TestFile.java	New fixture file containing MessageDigest.getInstance("MD5") annotated with the expected Noncompliant message.

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[sachin9058]

Hi @san-zrl I have opened this for adding regressions test for MD5 detection.. Can u take a look on this ??

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

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[n1ckl0sk0rtge]

LGTM! Thanks @sachin9058 :)