[json-node] Add JsonNodeMapper.properties() method

Match the feature of SimpleMapper and Jsonb.

json-core/src/main/java/io/avaje/json/simple/SimpleMapper.java

@@ -52,7 +52,16 @@ static Builder builder() {
   PropertyNames properties(String... names);
 
   /**
-   * Return a mapper for Object with more reading/writing options.
+   * Return a Type specific mapper for the given JsonAdapter.
+   *
+   * @param customAdapter The custom adapter to use.
+   * @param <T>           The type of the class to map to/from json.
+   * @return The Type specific mapper.
+   */
+  <T> Type<T> type(JsonAdapter<T> customAdapter);
+
+  /**
+   * Return a mapper for any json content.
    */
   Type<Object> object();
 
@@ -66,15 +75,6 @@ static Builder builder() {
    */
   Type<List<Object>> list();
 
-  /**
-   * Return a Type specific mapper for the given JsonAdapter.
-   *
-   * @param customAdapter The custom adapter to use.
-   * @param <T>           The type of the class to map to/from json.
-   * @return The Type specific mapper.
-   */
-  <T> Type<T> type(JsonAdapter<T> customAdapter);
-
   /**
    * Write the object to JSON string.
    * <p>

json-node/src/main/java/io/avaje/json/node/JsonNodeMapper.java

@@ -1,6 +1,7 @@
 package io.avaje.json.node;
 
 import io.avaje.json.JsonAdapter;
+import io.avaje.json.PropertyNames;
 import io.avaje.json.node.adapter.NodeAdapterBuilder;
 import io.avaje.json.simple.SimpleMapper;
 import io.avaje.json.stream.JsonStream;
@@ -19,8 +20,8 @@
  * static final JsonNodeMapper mapper = JsonNodeMapper.builder().build();
  *
  * JsonArray jsonArray = JsonArray.create()
- * .add(JsonInteger.of(42))
- * .add(JsonString.of("foo"));
+ * .add(42)
+ * .add("foo");
  *
  * var asJson = mapper.toJson(jsonArray);
  *
@@ -42,13 +43,21 @@ static Builder builder() {
   }
 
   /**
-   * Create a NodeMapper for the specific type given the JsonAdapter.
+   * Return the property names as PropertyNames.
+   * <p>
+   * Provides the option of optimising the writing of json for property names
+   * by having them already escaped and encoded rather than as plain strings.
+   */
+  PropertyNames properties(String... names);
+
+  /**
+   * Return a Type specific mapper for the given JsonAdapter.
    *
-   * @param customAdapter The type specific JsonAdapter to use.
-   * @param <T>           The specific custom type being mapped.
-   * @return The type specific NodeMapper.
+   * @param customAdapter The custom adapter to use.
+   * @param <T>           The type of the class to map to/from json.
+   * @return The Type specific mapper.
    */
-  <T> SimpleMapper.Type<T> mapper(JsonAdapter<T> customAdapter);
+  <T> SimpleMapper.Type<T> type(JsonAdapter<T> customAdapter);
 
   /**
    * Return a NodeMapper for ANY json content.

json-node/src/main/java/io/avaje/json/node/adapter/DJsonNodeMapper.java

@@ -2,6 +2,7 @@
 
 import io.avaje.json.JsonAdapter;
 import io.avaje.json.JsonReader;
+import io.avaje.json.PropertyNames;
 import io.avaje.json.node.*;
 import io.avaje.json.simple.SimpleMapper;
 import io.avaje.json.stream.JsonStream;
@@ -31,7 +32,12 @@ final class DJsonNodeMapper implements JsonNodeMapper {
   }
 
   @Override
-  public <T> SimpleMapper.Type<T> mapper(JsonAdapter<T> customAdapter) {
+  public PropertyNames properties(String... names) {
+    return jsonStream.properties(names);
+  }
+
+  @Override
+  public <T> SimpleMapper.Type<T> type(JsonAdapter<T> customAdapter) {
     return new DMapper<>(customAdapter, jsonStream);
   }
 

json-node/src/test/java/io/avaje/json/node/CustomAdapterTest.java

@@ -3,6 +3,7 @@
 import io.avaje.json.JsonAdapter;
 import io.avaje.json.JsonReader;
 import io.avaje.json.JsonWriter;
+import io.avaje.json.PropertyNames;
 import io.avaje.json.simple.SimpleMapper;
 import org.junit.jupiter.api.Test;
 
@@ -16,7 +17,21 @@ class CustomAdapterTest {
 
   static final JsonNodeMapper mapper = JsonNodeMapper.builder().build();
   static final MyAdapter myAdapter = new MyAdapter(mapper);
-  static final SimpleMapper.Type<MyCustomType> typeMapper = mapper.mapper(myAdapter);
+  static final SimpleMapper.Type<MyCustomType> typeMapper = mapper.type(myAdapter);
+
+  @Test
+  void propertyNames() {
+
+    var adapter = new MyAdapter2(mapper);
+    SimpleMapper.Type<MyCustomType> type = mapper.type(adapter);
+
+    var source = as("a", 1);
+    String asJson = type.toJson(source);
+    assertThat(asJson).isEqualTo("{\"foo\":\"a\",\"bar\":1}");
+
+    MyCustomType myCustomType = type.fromJson(asJson);
+    assertThat(myCustomType).isEqualTo(source);
+  }
 
   @Test
   void mapUsingCustomAdapter() {
@@ -110,4 +125,48 @@ public MyCustomType fromJson(JsonReader reader) {
       return myCustomType;
     }
   }
+
+  static class MyAdapter2 implements JsonAdapter<MyCustomType> {
+
+    final SimpleMapper.Type<JsonObject> objectMapper;
+    final PropertyNames names;
+
+    public MyAdapter2(JsonNodeMapper mapper) {
+      this.objectMapper = mapper.objectMapper();
+      this.names = mapper.properties("foo", "bar");
+    }
+
+    @Override
+    public void toJson(JsonWriter writer, MyCustomType value) {
+      writer.beginObject(names);
+      writer.name(0);
+      writer.value(value.foo);
+      writer.name(1);
+      writer.value(value.bar);
+      writer.endObject();
+    }
+
+    @Override
+    public MyCustomType fromJson(JsonReader reader) {
+      MyCustomType myCustomType = new MyCustomType();
+      reader.beginObject(names);
+
+      String name;
+      while (reader.hasNextField()) {
+        name = reader.nextField();
+        switch (name) {
+          case "foo":
+            myCustomType.foo = reader.readString();
+            break;
+          case "bar":
+            myCustomType.bar = reader.readInt();
+            break;
+          default:
+            reader.unmappedField(name);
+            reader.skipValue();
+        }
+      }
+      return myCustomType;
+    }
+  }
 }