Remove usage of Jackson TypeReference.

Motivation:

Jackson's TypeReference is only supported by the DatabindCodec. A few methods declaring TypeReference are still available on JacksonCodec and JsonEvent, such methods should be removed because the lead to incomplete usage of JacksonCodec and will simply not work at all with potential other implementations of the JSON spi.

Changes:

Remove methods declaring TypeReference and update tests accordingly.

vertx-core/src/main/java/io/vertx/core/json/jackson/JacksonCodec.java

@@ -13,7 +13,6 @@
 
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.io.SegmentedStringWriter;
-import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.core.util.BufferRecycler;
 import com.fasterxml.jackson.core.util.ByteArrayBuilder;
 import io.netty.buffer.ByteBufInputStream;
@@ -30,8 +29,6 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.Writer;
-import java.lang.reflect.ParameterizedType;
-import java.lang.reflect.Type;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.time.Instant;
@@ -67,28 +64,16 @@ public <T> T fromString(String json, Class<T> clazz) throws DecodeException {
     return fromParser(createParser(json), clazz);
   }
 
-  public <T> T fromString(String str, TypeReference<T> typeRef) throws DecodeException {
-    return fromString(str, classTypeOf(typeRef));
-  }
-
   @Override
   public <T> T fromBuffer(Buffer json, Class<T> clazz) throws DecodeException {
     return fromParser(createParser(json), clazz);
   }
 
-  public <T> T fromBuffer(Buffer buf, TypeReference<T> typeRef) throws DecodeException {
-    return fromBuffer(buf, classTypeOf(typeRef));
-  }
-
   @Override
   public <T> T fromValue(Object json, Class<T> toValueType) {
     throw new DecodeException("Mapping " + toValueType.getName() + "  is not available without Jackson Databind on the classpath");
   }
 
-  public <T> T fromValue(Object json, TypeReference<T> type) {
-    throw new DecodeException("Mapping " + type.getType().getTypeName() + " is not available without Jackson Databind on the classpath");
-  }
-
   @Override
   public String toString(Object object, boolean pretty) throws EncodeException {
     BufferRecycler br = factory._getBufferRecycler();
@@ -378,17 +363,6 @@ private static void encodeNumber(JsonGenerator generator, Object json) throws IO
     }
   }
 
-  private static <T> Class<T> classTypeOf(TypeReference<T> typeRef) {
-    Type type = typeRef.getType();
-    if (type instanceof Class) {
-      return (Class<T>) type;
-    } else if (type instanceof ParameterizedType) {
-      return (Class<T>) ((ParameterizedType)type).getRawType();
-    } else {
-      throw new DecodeException();
-    }
-  }
-
   private static <T> T cast(Object o, Class<T> clazz) {
     if (o instanceof Map) {
       if (!clazz.isAssignableFrom(Map.class)) {
@@ -449,28 +423,4 @@ private static <T> T cast(Object o, Class<T> clazz) {
       return clazz.cast(o);
     }
   }
-
-  /**
-   * Decode a given JSON string to a POJO of the given type.
-   * @param str the JSON string.
-   * @param type the type to map to.
-   * @param <T> the generic type.
-   * @return an instance of T
-   * @throws DecodeException when there is a parsing or invalid mapping.
-   */
-  public static <T> T decodeValue(String str, TypeReference<T> type) throws DecodeException {
-    return JacksonFactory.CODEC.fromString(str, type);
-  }
-
-  /**
-   * Decode a given JSON buffer to a POJO of the given class type.
-   * @param buf the JSON buffer.
-   * @param type the type to map to.
-   * @param <T> the generic type.
-   * @return an instance of T
-   * @throws DecodeException when there is a parsing or invalid mapping.
-   */
-  public static <T> T decodeValue(Buffer buf, TypeReference<T> type) throws DecodeException {
-    return JacksonFactory.CODEC.fromBuffer(buf, type);
-  }
 }

vertx-core/src/main/java/io/vertx/core/parsetools/JsonEvent.java

@@ -11,18 +11,16 @@
 
 package io.vertx.core.parsetools;
 
-import com.fasterxml.jackson.core.type.TypeReference;
 import io.vertx.codegen.annotations.DataObject;
 import io.vertx.codegen.annotations.GenIgnore;
-import io.vertx.codegen.annotations.VertxGen;
 import io.vertx.core.buffer.Buffer;
 import io.vertx.core.json.JsonArray;
 import io.vertx.core.json.JsonObject;
 
 import java.time.Instant;
 
 /**
- * A JSON event emited by the {@link JsonParser}.
+ * A JSON event emitted by the {@link JsonParser}.
  *
  * @author <a href="mailto:julien@julienviet.com">Julien Viet</a>
  */
@@ -156,13 +154,4 @@ public interface JsonEvent {
    */
   <T> T mapTo(Class<T> type);
 
-  /**
-   * Decodes and returns the current value as the specified {@code type}.
-   *
-   * @param type the type to decode the value to
-   * @return the decoded value
-   */
-  @GenIgnore(GenIgnore.PERMITTED_TYPE)
-  <T> T mapTo(TypeReference<T> type);
-
 }

vertx-core/src/main/java/io/vertx/core/parsetools/impl/JsonEventImpl.java

@@ -101,15 +101,6 @@ public <T> T mapTo(Class<T> type) {
     }
   }
 
-  @Override
-  public <T> T mapTo(TypeReference<T> type) {
-    try {
-      return JacksonFactory.CODEC.fromValue(value, type);
-    } catch (Exception e) {
-      throw new DecodeException(e.getMessage(), e);
-    }
-  }
-
   @Override
   public Integer integerValue() {
     if (value != null) {

vertx-core/src/test/java/io/vertx/tests/json/JacksonDatabindTest.java

@@ -23,7 +23,6 @@
 import io.vertx.core.json.JsonArray;
 import io.vertx.core.json.JsonObject;
 import io.vertx.core.json.jackson.DatabindCodec;
-import io.vertx.core.json.jackson.JacksonCodec;
 import io.vertx.test.core.TestUtils;
 import io.vertx.test.core.VertxTestBase;
 import org.junit.Test;
@@ -57,13 +56,15 @@ public void testGenericDecoding() {
     String json = Json.encode(Collections.singletonList(original));
     List<Pojo> correct;
 
-    correct = JacksonCodec.decodeValue(json, new TypeReference<List<Pojo>>() {
+    DatabindCodec databindCodec = new DatabindCodec();
+
+    correct = databindCodec.fromString(json, new TypeReference<List<Pojo>>() {
     });
     assertTrue(((List) correct).get(0) instanceof Pojo);
     assertEquals(original.value, correct.get(0).value);
 
     // same must apply if instead of string we use a buffer
-    correct = JacksonCodec.decodeValue(Buffer.buffer(json, "UTF8"), new TypeReference<List<Pojo>>() {
+    correct = databindCodec.fromBuffer(Buffer.buffer(json, "UTF8"), new TypeReference<List<Pojo>>() {
     });
     assertTrue(((List) correct).get(0) instanceof Pojo);
     assertEquals(original.value, correct.get(0).value);