Add JsonReader.unwrap() to access underlying JsonParser when using avaje-jsonb-jackson

blackbox-test/src/test/java/org/example/customer/BasicPubFieldsTest.java

@@ -2,7 +2,6 @@
 
 import io.avaje.jsonb.JsonType;
 import io.avaje.jsonb.Jsonb;
-//import io.avaje.jsonb.jackson.JacksonIOAdapter;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;

jsonb-jackson/src/main/java/io/avaje/jsonb/jackson/JacksonReader.java

@@ -22,6 +22,11 @@ final class JacksonReader implements JsonReader {
     this.failOnUnknown = failOnUnknown;
   }
 
+  @Override
+  public <T> T unwrap(Class<T> type) {
+    return type.cast(parser);
+  }
+
   @Override
   public void close() {
     try {

jsonb-jackson/src/main/java/io/avaje/jsonb/jackson/JacksonWriter.java

@@ -65,10 +65,9 @@ public void pretty(boolean pretty) {
     }
   }
 
-  @SuppressWarnings("unchecked")
   @Override
-  public <T> T unwrap(Class<T> underlying) {
-    return (T) generator;
+  public <T> T unwrap(Class<T> type) {
+    return type.cast(generator);
   }
 
   @Override

jsonb-jackson/src/test/java/io/avaje/jsonb/jackson/UnwrapJacksonParserTest.java

@@ -0,0 +1,33 @@
+package io.avaje.jsonb.jackson;
+
+import com.fasterxml.jackson.core.JsonLocation;
+import com.fasterxml.jackson.core.JsonParser;
+import io.avaje.jsonb.JsonReader;
+import io.avaje.jsonb.JsonType;
+import io.avaje.jsonb.Jsonb;
+import org.junit.jupiter.api.Test;
+
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class UnwrapJacksonParserTest {
+
+  Jsonb jsonb = Jsonb.builder().build();
+
+  @Test
+  void unwrap() {
+    try (JsonReader reader = jsonb.reader("{\"id\":42,\"name\":\"rob\"}")) {
+      JsonParser jsonParser = reader.unwrap(JsonParser.class);
+      JsonLocation location = jsonParser.currentLocation();
+
+      assertThat(location.toString()).isEqualTo("[Source: (String)\"{\"id\":42,\"name\":\"rob\"}\"; line: 1, column: 1]");
+
+      JsonType<Map<String, Object>> jsonMap = jsonb.type(Object.class).map();
+
+      Map<String, Object> map = jsonMap.fromJson(reader);
+      assertThat(map.get("id")).isEqualTo(42D);
+      assertThat(map.get("name")).isEqualTo("rob");
+    }
+  }
+}

jsonb/src/main/java/io/avaje/jsonb/JsonReader.java

@@ -26,6 +26,20 @@
  */
 public interface JsonReader extends Closeable {
 
+  /**
+   * Unwrap and return the underlying JsonParser.
+   * <p>
+   * When using avaje-jsonb-jackson this will return the underlying Jackson JsonParser.
+   *
+   * <pre>{@code
+   *
+   * // when using avaje-jsonb-jackson
+   * var jacksonParser = jsonReader.unwrap(JsonParser.class);
+   *
+   * }</pre>
+   */
+  <T> T unwrap(Class<T> type);
+
   /**
    * Read the beginning of an ARRAY or x-json-stream (new line delimited json content).
    */

jsonb/src/main/java/io/avaje/jsonb/JsonWriter.java

@@ -49,7 +49,7 @@ public interface JsonWriter extends Closeable, Flushable {
    *
    * }</pre>
    */
-  <T> T unwrap(Class<T> underlying);
+  <T> T unwrap(Class<T> type);
 
   /**
    * Set to serialise null values or not.

jsonb/src/main/java/io/avaje/jsonb/core/ObjectJsonReader.java

@@ -24,6 +24,11 @@ final class ObjectJsonReader implements JsonReader {
     this.currentValue = source;
   }
 
+  @Override
+  public <T> T unwrap(Class<T> type) {
+    throw new UnsupportedOperationException();
+  }
+
   @Override
   public void unmappedField(String fieldName) {
 

jsonb/src/main/java/io/avaje/jsonb/spi/DelegateJsonWriter.java

@@ -17,8 +17,8 @@ public DelegateJsonWriter(JsonWriter delegate) {
   }
 
   @Override
-  public <T> T unwrap(Class<T> underlying) {
-    return delegate.unwrap(underlying);
+  public <T> T unwrap(Class<T> type) {
+    return delegate.unwrap(type);
   }
 
   @Override

jsonb/src/main/java/io/avaje/jsonb/stream/JsonReadAdapter.java

@@ -16,6 +16,11 @@ final class JsonReadAdapter implements JsonReader {
     this.failOnUnknown = failOnUnknown;
   }
 
+  @Override
+  public <T> T unwrap(Class<T> type) {
+    return type.cast(reader);
+  }
+
   @Override
   public void beginStream() {
     reader.startStream();

jsonb/src/main/java/io/avaje/jsonb/stream/JsonWriteAdapter.java

@@ -25,10 +25,9 @@ final class JsonWriteAdapter implements JsonWriter {
     this.serializeEmpty = serializeEmpty;
   }
 
-  @SuppressWarnings("unchecked")
   @Override
-  public <T> T unwrap(Class<T> underlying) {
-    return (T) generator;
+  public <T> T unwrap(Class<T> type) {
+    return type.cast(generator);
   }
 
   @Override