diff --git a/java/README.md b/java/README.md
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+# Show, Don't Tell — Java exercise workspace
+
+Java track for the "Show, Don't Tell — Using Examples with Coding Agents" exercise (Java 21 / Maven / JUnit 5 / AssertJ).
+
+## Prerequisites
+
+- Java 21 (Temurin) and Maven, versions pinned in `mise.toml`
+- If you use [mise](https://mise.jdx.dev): `mise install` installs both
+
+## Build and run the tests
+
+```sh
+mvn test
+```
+
+## Layout
+
+| Module | Contents |
+| --- | --- |
+| `order-domain`, `order-tests` | Order domain with discount behaviour, and its tests (Round 1) |
+| `order-book-domain`, `order-book-tests` | OrderBook state machine, and its integration tests (Round 2) |
+
+The exercise starts in its START state: all tests are green, the refactoring participants should do is NOT applied. The custom matcher example lives in `order-tests` (`OrderStateAssertion`).
diff --git a/java/mise.toml b/java/mise.toml
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+++ b/java/mise.toml
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+[tools]
+java = "temurin-21.0.9+10.0.LTS"
+maven = "3.9.16"
diff --git a/java/order-book-domain/pom.xml b/java/order-book-domain/pom.xml
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index 0000000..2168561
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+++ b/java/order-book-domain/pom.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>dev.learninghour.showdonttell</groupId>
+    <artifactId>show-dont-tell-java</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+  </parent>
+
+  <artifactId>order-book-domain</artifactId>
+  <packaging>jar</packaging>
+</project>
diff --git a/java/order-book-tests/pom.xml b/java/order-book-tests/pom.xml
new file mode 100644
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+++ b/java/order-book-tests/pom.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>dev.learninghour.showdonttell</groupId>
+    <artifactId>show-dont-tell-java</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+  </parent>
+
+  <artifactId>order-book-tests</artifactId>
+  <packaging>jar</packaging>
+
+  <dependencies>
+    <dependency>
+      <groupId>dev.learninghour.showdonttell</groupId>
+      <artifactId>order-book-domain</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>${junit.version}</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+</project>
diff --git a/java/order-domain/pom.xml b/java/order-domain/pom.xml
new file mode 100644
index 0000000..935916d
--- /dev/null
+++ b/java/order-domain/pom.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>dev.learninghour.showdonttell</groupId>
+    <artifactId>show-dont-tell-java</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+  </parent>
+
+  <artifactId>order-domain</artifactId>
+  <packaging>jar</packaging>
+</project>
diff --git a/java/order-tests/pom.xml b/java/order-tests/pom.xml
new file mode 100644
index 0000000..168db8e
--- /dev/null
+++ b/java/order-tests/pom.xml
@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>dev.learninghour.showdonttell</groupId>
+    <artifactId>show-dont-tell-java</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+  </parent>
+
+  <artifactId>order-tests</artifactId>
+  <packaging>jar</packaging>
+
+  <dependencies>
+    <dependency>
+      <groupId>dev.learninghour.showdonttell</groupId>
+      <artifactId>order-domain</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>${junit.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.assertj</groupId>
+      <artifactId>assertj-core</artifactId>
+      <version>${assertj.version}</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+</project>
diff --git a/java/pom.xml b/java/pom.xml
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index 0000000..2140662
--- /dev/null
+++ b/java/pom.xml
@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>dev.learninghour.showdonttell</groupId>
+  <artifactId>show-dont-tell-java</artifactId>
+  <version>1.0.0-SNAPSHOT</version>
+  <packaging>pom</packaging>
+
+  <modules>
+    <module>order-domain</module>
+    <module>order-book-domain</module>
+    <module>order-tests</module>
+    <module>order-book-tests</module>
+  </modules>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <maven.compiler.release>21</maven.compiler.release>
+    <junit.version>5.14.4</junit.version>
+    <assertj.version>3.27.7</assertj.version>
+  </properties>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>3.5.6</version>
+      </plugin>
+    </plugins>
+  </build>
+</project>