Add AttributeFilterChain.remove() method

[Copilot]

Implementation Plan for AttributeFilterChain.remove()

• Add remove(AttributeFilter filter) method to AttributeFilterChain class
• Add comprehensive tests for the remove() method covering:
  • Remove from empty chain
  • Remove single filter
  • Remove first/last filter from multiple filters
  • Remove non-existent filter
  • Remove null filter (consistency check)
  • Verify chain still functions correctly after removal
• Add null parameter validation for consistency with addFirst/addLast
• Format code using spotless
• Compile and verify changes
• Get final preflight approval
• Address review feedback: Use assertThrows for exception testing

Implementation Summary

Successfully implemented AttributeFilterChain.remove() method as requested in issue #1697.

Key Features:

• Synchronized method for thread-safety
• Null parameter validation for consistency with addFirst/addLast methods
• Safe handling of empty chains
• Method chaining support (returns this)
• Removes only the first occurrence (standard Deque behavior)

Testing:
All 8 test cases pass successfully, using JUnit 5's assertThrows for clean exception testing.

Original prompt

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This section details on the original issue you should resolve

<issue_title>AttributeFilters can't be removed from AccessControlFilter</issue_title>
<issue_description>Implement an AttributeFilterChain.remove() method.

Something like:

  public synchronized AttributeFilterChain remove(AttributeFilter filter) {
    ConcurrentLinkedDeque<AttributeFilter> deque = filterDeque;
    if (deque != null) {
      deque.remove(filter);
    }
    return this;
  }

Originally posted by @kevinherron in #1697 (comment)</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes AttributeFilters can't be removed from AccessControlFilter #1698

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[kevinherron]

See comment about assertThrows

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

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• repo.eclipse.org
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[Copilot]

See comment about assertThrows

Already addressed in commit 1800900 - the test now uses assertThrows instead of try-catch.

[Copilot]

Pull request overview

Adds support for removing an AttributeFilter from an AttributeFilterChain, addressing the inability to remove filters once added (per issue #1697/#1698).

Changes:

• Added AttributeFilterChain.remove(AttributeFilter) with null validation and safe no-op behavior for empty chains.
• Added a comprehensive JUnit 5 test suite for remove() covering empty chains, first/middle/last removal, non-existent filter removal, and null handling.

Reviewed changes

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

File	Description
opc-ua-sdk/sdk-server/src/main/java/org/eclipse/milo/opcua/sdk/server/nodes/filters/AttributeFilterChain.java	Introduces remove(AttributeFilter) to delete a filter instance from the chain while preserving fluent chaining semantics.
opc-ua-sdk/sdk-server/src/test/java/org/eclipse/milo/opcua/sdk/server/nodes/filters/AttributeFilterChainTest.java	Adds focused unit tests validating correctness and post-removal behavior of the filter chain.

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