Part 2: records need no module, annotation or -parameters flag

src/main/java/com/ankurm/jackson3/part2modernjava/C01RecordRoundTrip.java

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+package com.ankurm.jackson3.part2modernjava;
+
+import tools.jackson.databind.json.JsonMapper;
+
+/**
+ * Post: Jackson with Records, Optionals, Sealed Classes
+ *       https://ankurm.com/jackson-java-records-optionals/
+ * Section: "Jackson with Java Records"
+ *
+ * Records need no module, no annotation and no -parameters compiler flag in
+ * Jackson 3. Check the pom: there is no jackson-module-parameter-names dependency
+ * and no <compilerArgs>.
+ */
+public class C01RecordRoundTrip {
+
+    /** A concise, immutable data transfer object. */
+    public record ProductRecord(Long productId, String productName, double unitPrice) { }
+
+    public static void main(String[] args) {
+        JsonMapper mapper = JsonMapper.builder().build();
+
+        // Serialise: Record -> JSON. Accessor methods replace getters.
+        ProductRecord product = new ProductRecord(101L, "Wireless Keyboard", 49.99);
+        String jsonOutput = mapper.writeValueAsString(product);
+        System.out.println(jsonOutput);
+
+        // Deserialise: JSON -> Record. The canonical constructor is located through
+        // the RecordComponent reflection API (Java 16+), not through parameter names.
+        String json = "{\"productId\":101,\"productName\":\"Wireless Keyboard\",\"unitPrice\":49.99}";
+        ProductRecord restored = mapper.readValue(json, ProductRecord.class);
+        System.out.println(restored.productName());
+
+        // Records also give you equals() for free, so a round-trip is assertable.
+        System.out.println("round-trip equal: " + product.equals(restored));
+    }
+}