[java] simplify unmodifiable collections operations

[iampopovich]

User description

🔗 Related Issues

💥 What does this PR do?

This pull request refactors several places in the codebase to use modern Java collection factory methods (Map.of, Map.ofEntries, Map.copyOf, and List.of) instead of older patterns that manually create and wrap collections. This improves code readability, reduces boilerplate, and leverages immutable collections directly from the JDK.

Refactoring to use modern collection factory methods:

• Replaced manual construction and wrapping of maps with Map.of in DeviceRotation.parameters() for more concise and immutable map creation.
• Updated CapabilityCount and CreateSessionRequest to use Map.copyOf for immutable maps instead of unmodifiableMap(new HashMap<>(...)). [1] [2]
• Changed NumberCoercer.PRIMITIVE_NUMBER_TYPES initialization to use Map.ofEntries for cleaner and more direct mapping.
• Refactored VirtualAuthenticatorOptions.toMap() to use Map.ofEntries instead of manual map creation and wrapping.

Modernizing collection usage in tests:

• Updated test code in DefaultSlotSelectorTest to use List.of instead of Arrays.asList, aligning with modern Java idioms.

🔧 Implementation Notes

I primarily changed unmodifiable collections that do not affect the contract of classes and methods
There are still unmodifiableSet and unmodifiableMap types in the code, but I haven't figured out yet if I can do anything with them.

💡 Additional Considerations

🔄 Types of changes

• Cleanup (formatting, renaming)

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PR Type

Enhancement

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Description

• Replace manual collection wrapping with modern Java factory methods

• Use Map.of, Map.copyOf, and Map.ofEntries for cleaner code

• Eliminate unnecessary HashMap and Collections.unmodifiableMap patterns

• Update test code to use List.of instead of Arrays.asList

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Diagram Walkthrough

flowchart LR
  A["Manual HashMap + unmodifiableMap"] -->|Refactor| B["Map.of / Map.copyOf"]
  C["Arrays.asList"] -->|Modernize| D["List.of"]
  B -->|Result| E["Cleaner, more concise code"]
  D -->|Result| E

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File Walkthrough

	Relevant files
Enhancement	DeviceRotation.java Simplify map creation using Map.of                                              java/src/org/openqa/selenium/DeviceRotation.java Replaced manual HashMap construction with Map.of in parameters() method Removed unnecessary imports for Collections and HashMap Simplified map creation from 5 lines to 1 line +1/-7      CapabilityCount.java Use Map.copyOf for immutable map creation                                java/src/org/openqa/selenium/grid/data/CapabilityCount.java Replaced unmodifiableMap(new HashMap<>(counts)) with Map.copyOf(counts) Removed static import of unmodifiableMap Simplified constructor initialization +1/-2      CreateSessionRequest.java Modernize metadata map initialization                                        java/src/org/openqa/selenium/grid/data/CreateSessionRequest.java Replaced unmodifiableMap(new HashMap<>(...)) with Map.copyOf for metadata field Removed static import of unmodifiableMap Removed unused HashMap import +1/-3      NumberCoercer.java Use Map.ofEntries for primitive type mapping                          java/src/org/openqa/selenium/json/NumberCoercer.java Refactored PRIMITIVE_NUMBER_TYPES static initialization to use Map.ofEntries Removed manual HashMap construction and Collections.unmodifiableMap wrapping Simplified from 9 lines to 6 lines with improved readability +8/-11    VirtualAuthenticatorOptions.java Simplify toMap method using Map.ofEntries                                java/src/org/openqa/selenium/virtualauthenticator/VirtualAuthenticatorOptions.java Refactored toMap() method to use Map.ofEntries instead of manual map construction Removed unnecessary HashMap and Collections.unmodifiableMap usage Simplified from 8 lines to 6 lines +7/-10
Tests	DefaultSlotSelectorTest.java Modernize test collections to use List.of                                java/test/org/openqa/selenium/grid/distributor/selector/DefaultSlotSelectorTest.java Replaced Arrays.asList with List.of in four test cases Modernized collection initialization to use Java 9+ idioms Improved code consistency and readability +4/-4

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[qodo-code-review]

PR Compliance Guide 🔍

Below is a summary of compliance checks for this PR:

Security Compliance
⚪	Unchecked nulls in Map.of Description: Using Map.of for parameters() creates an unmodifiable map that throws NullPointerException if any value is null; if x, y, or z can be null via external input, this may cause runtime exceptions and potential denial-of-service paths. DeviceRotation.java [96-98] Referred Code public Map<String, Integer> parameters() { return Map.of("x", this.x, "y", this.y, "z", this.z); }
	Null-sensitive immutable map Description: Map.ofEntries throws NullPointerException if any entry value is null; if optional fields like transport or protocol can be unset, this could cause runtime failures on serialization paths. VirtualAuthenticatorOptions.java [95-103] Referred Code public Map<String, Object> toMap() { return Map.ofEntries( Map.entry("protocol", protocol.id), Map.entry("transport", transport.id), Map.entry("hasResidentKey", hasResidentKey), Map.entry("hasUserVerification", hasUserVerification), Map.entry("isUserConsenting", isUserConsenting), Map.entry("isUserVerified", isUserVerified)); }
Ticket Compliance
🟡	🎫 #5678 🔴 Investigate and resolve repeated "Error: ConnectFailure (Connection refused)" when instantiating multiple ChromeDriver instances on Ubuntu 16.04 with Chrome 65 and ChromeDriver 2.35 using Selenium 3.9.0. Ensure subsequent ChromeDriver instantiations do not log connection failures after the first succeeds. ⚪ Provide guidance or code changes that address environment-specific causes if applicable.
🟡	🎫 #1234 🔴 Fix regression where WebDriver 2.48.0/2.48.2 does not trigger JavaScript in link href on click() in Firefox 42, which worked in 2.47.1. Add tests to verify click() triggers JavaScript href handlers in affected environments.
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Passed
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed
⚪	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: No audit logs: The changes refactor collection creation without introducing or modifying any logging for critical actions, so there is no evidence that relevant actions are audited. Referred Code public CreateSessionRequest( Set<Dialect> downstreamDialects, Capabilities capabilities, Map<String, Object> metadata) { this.downstreamDialects = unmodifiableSet(new HashSet<>(Require.nonNull("Downstream dialects", downstreamDialects))); this.capabilities = ImmutableCapabilities.copyOf(Require.nonNull("Capabilities", capabilities)); this.metadata = Map.copyOf(Require.nonNull("Metadata", metadata)); }
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: No error handling: The refactor changes map initialization only and does not add error handling for potential edge cases, leaving uncertainty whether failures are handled elsewhere. Referred Code class NumberCoercer<T extends Number> extends TypeCoercer<T> { private static final Map<Class<?>, Class<?>> PRIMITIVE_NUMBER_TYPES; static { PRIMITIVE_NUMBER_TYPES = Map.ofEntries( Map.entry(byte.class, Byte.class), Map.entry(double.class, Double.class), Map.entry(float.class, Float.class), Map.entry(int.class, Integer.class), Map.entry(long.class, Long.class), Map.entry(short.class, Short.class)); }
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: Input validation unclear: The constructor now uses Map.copyOf for metadata but does not show validation or sanitization of external inputs within the diff, so secure handling cannot be confirmed. Referred Code public CreateSessionRequest( Set<Dialect> downstreamDialects, Capabilities capabilities, Map<String, Object> metadata) { this.downstreamDialects = unmodifiableSet(new HashSet<>(Require.nonNull("Downstream dialects", downstreamDialects))); this.capabilities = ImmutableCapabilities.copyOf(Require.nonNull("Capabilities", capabilities)); this.metadata = Map.copyOf(Require.nonNull("Metadata", metadata)); }
Update

Compliance status legend

🟢 - Fully Compliant
🟡 - Partial Compliant
🔴 - Not Compliant
⚪ - Requires Further Human Verification
🏷️ - Compliance label

[qodo-code-review]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	Use Map.of for conciseness Replace Map.ofEntries(...) with the more concise Map.of(...) to initialize the PRIMITIVE_NUMBER_TYPES map, as there are fewer than 10 entries. java/src/org/openqa/selenium/json/NumberCoercer.java [32-39] PRIMITIVE_NUMBER_TYPES = - Map.ofEntries( - Map.entry(byte.class, Byte.class), - Map.entry(double.class, Double.class), - Map.entry(float.class, Float.class), - Map.entry(int.class, Integer.class), - Map.entry(long.class, Long.class), - Map.entry(short.class, Short.class)); + Map.of( + byte.class, Byte.class, + double.class, Double.class, + float.class, Float.class, + int.class, Integer.class, + long.class, Long.class, + short.class, Short.class); Apply / Chat Suggestion importance[1-10]: 4 __ Why: The suggestion correctly identifies a more concise way to initialize the map using Map.of() instead of Map.ofEntries(), which aligns with the PR's goal of code modernization and simplification.	Low
Update

[asolntsev]

Generally OK, but need to check if this code is compilable by Java version used in Selenium.

[iampopovich]

Generally OK, but need to check if this code is compilable by Java version used in Selenium.

@asolntsev
functionality requires java 10 as minimal version, Seleinum uses java 17 for development

selenium/README.md

Line 55 in 3a0b3ae

* Java JDK version 17 or greater (e.g., [Java 17 Temurin](https://adoptium.net/temurin/releases/?version=17))

As far as I remember, the project supports JDK 11 as a minimum version. I couldn't find any mention of a JDK version lower than 11 anywhere in the configurations.
I ran tests in CI and compilation was successful https://github.com/iampopovich/selenium/actions/runs/19912486873

[Copilot]

Pull request overview

This pull request modernizes collection creation throughout the Selenium Java codebase by replacing verbose legacy patterns with concise Java 9+ factory methods. The changes eliminate boilerplate code while maintaining the immutability guarantees of the original implementations.

Key changes:

• Replaced Collections.unmodifiableMap(new HashMap<>(...)) with Map.of, Map.copyOf, and Map.ofEntries
• Replaced Arrays.asList with List.of in test code where appropriate
• Removed unnecessary imports for Collections, HashMap, and related classes

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
DeviceRotation.java	Simplified parameters() method using Map.of for three key-value pairs
CapabilityCount.java	Replaced unmodifiableMap(new HashMap<>()) with Map.copyOf in constructor
CreateSessionRequest.java	Replaced unmodifiableMap(new HashMap<>()) with Map.copyOf for metadata field
NumberCoercer.java	Refactored static initializer to use Map.ofEntries for primitive type mapping
VirtualAuthenticatorOptions.java	Replaced manual map construction with Map.ofEntries in toMap() method
DefaultSlotSelectorTest.java	Modernized test data creation using List.of instead of Arrays.asList

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