AssertJ QuickFIX/J

Fluent, semantic assertions for normal QuickFIX/J Message values. Use it to check FIX versions, message types, headers, trailers, and typed field values with useful failure diagnostics.

Why use it?

Plain QuickFIX/J tests often repeat tag lookups, conversions, and hand-written error messages. AssertJ QuickFIX/J provides:

• Assertions.assertThat(Message) as the fluent entry point.
• FIX 4.0 through 4.4 and FIXT 1.1 application-version assertions.
• Semantic message methods such as isNewOrderSingle() and isExecutionReport().
• Header and trailer chaining with header(), trailer(), and and().
• Dictionary-aware, typed hasFieldValue(tag, value) checks.
• Generic hasMsgType(code) and hasMsgTypeName(name) checks.
• One test artifact that lets the consumer select QuickFIX/J.

Requirements and compatibility

Library	Java	QuickFIX/J	Status
1.1.x (main)	11+	2.3.2 and 3.0.2	In development; both are release gates
1.0.x	11+	built with 2.3.2	Published maintenance line

CI runs Java 11, 17, and 21. See the full compatibility policy.

Installation

The current release is on Maven Central. Add it in test scope:

<dependency>
  <groupId>io.allune</groupId>
  <artifactId>assertj-quickfixj</artifactId>
  <version>1.0.0</version>
  <scope>test</scope>
</dependency>

testImplementation("io.allune:assertj-quickfixj:1.0.0")

QuickFIX/J is intentionally provided. Your application or test suite must supply quickfixj-core and the message module it uses. This library does not change the engine version selected by the application.

Quick start

import quickfix.Message;
import quickfix.field.BeginString;
import quickfix.field.MsgType;

import quickfix.field.OrdType;
import quickfix.field.Side;
import quickfix.field.Symbol;

import static io.allune.quickfixj.api.Assertions.assertThat;

Message message = new Message();
message.getHeader().setString(BeginString.FIELD, "FIX.4.4");
message.getHeader().setString(MsgType.FIELD, "D");
message.setString(Symbol.FIELD, "AAPL");
message.setChar(Side.FIELD, Side.BUY);
message.setChar(OrdType.FIELD, OrdType.LIMIT);

assertThat(message)
    .isVersion44()
    .isNewOrderSingle()
    .hasFieldValue(Symbol.FIELD, "AAPL")
    .hasFieldValue(Side.FIELD, Side.BUY)
    .hasFieldValue(OrdType.FIELD, OrdType.LIMIT);

Headers and trailers

assertThat(message)
    .header()
        .hasSenderCompID("CLIENT")
        .hasTargetCompID("BROKER")
    .and()
    .trailer()
        .hasChecksum("074")
    .and()
    .isNewOrderSingle();

Message names and FIXT 1.1

assertThat(message).hasMsgTypeName("NewOrderSingle");

For FIXT 1.1, the library resolves the application dictionary from header tag 1128 (ApplVerID). FIX 5.0, FIX 5.0 SP1, and FIX 5.0 SP2 are supported by isVersion50(), isVersion50sp1(), and isVersion50sp2().

Custom dictionaries

DataDictionary dictionary = new DataDictionary("path/to/FIX44-custom.xml");
assertThat(message)
    .usingDataDictionary("FIX.4.4", dictionary)
    .hasFieldValue(6000, "CustomValue");

In 1.x, custom dictionary overrides are stored in a process-wide concurrent registry. Access is thread-safe, but conflicting overrides for the same FIX version can affect parallel tests and remain active for the process. Isolate such tests. Assertion-scoped configuration is planned for 2.0; see ADR 0003.

FixMock integration

FixMock exposes recorded traffic as QuickFIX/J Message values, so no adapter is required:

Message received = fixMock.awaitMessage(newOrderSingle(), Duration.ofSeconds(5));

assertThat(received)
    .isVersion44()
    .isNewOrderSingle()
    .hasFieldValue(Symbol.FIELD, "AAPL");

Keep both libraries in test scope. The Spring Boot starter interoperability suite consumes their released artifacts and does not create a source dependency between repositories.

Build locally

Requirements are JDK 11+ and Maven 3.8.6+. The canonical command is:

mvn --batch-mode verify

Verify QuickFIX/J 3.0.2 explicitly with:

mvn --batch-mode -Dquickfixj.version=3.0.2 verify

CI runs both 2.3.2 and 3.0.2 on Java 11, 17, and 21. It also checks dependency convergence, coverage, public API compatibility with 1.0.0, and a separately built packaged consumer.

Documentation

• Documentation index
• Compatibility
• Roadmap
• Contributing
• Support policy
• Release process
• Release checklist
• Changelog
• Architecture decisions
• Security policy

Current limitations

• Repeating groups and components do not yet have dedicated fluent assertions.
• Custom dictionary overrides are process-wide in 1.x.
• Exact failure-message text is not a stable API unless a release note says otherwise.

License

Apache License 2.0.