#20 - Add builder for JacksonAdapter

Author: rbygrave

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

@@ -18,6 +18,56 @@
  */
 public class JacksonAdapter implements JsonStreamAdapter {
 
+  /**
+   * Used to build JacksonAdapter with custom settings.
+   */
+  public static class Builder {
+
+    private JsonFactory jsonFactory;
+    private boolean serializeNulls;
+    private boolean serializeEmpty;
+    private boolean failOnUnknown;
+
+    /**
+     * Set the Jackson JsonFactory to use.
+     */
+    public Builder jsonFactory(JsonFactory jsonFactory) {
+      this.jsonFactory = jsonFactory;
+      return this;
+    }
+
+    /**
+     * Set to true to serialize nulls. Defaults to false.
+     */
+    public Builder serializeNulls(boolean serializeNulls) {
+      this.serializeNulls = serializeNulls;
+      return this;
+    }
+
+    /**
+     * Set to true to serialize empty collections. Defaults to false.
+     */
+    public Builder serializeEmpty(boolean serializeEmpty) {
+      this.serializeEmpty = serializeEmpty;
+      return this;
+    }
+
+    /**
+     * Set to true to fail on unknown properties. Defaults to false.
+     */
+    public Builder failOnUnknown(boolean failOnUnknown) {
+      this.failOnUnknown = failOnUnknown;
+      return this;
+    }
+
+    /**
+     * Build and return the JacksonAdapter.
+     */
+    public JacksonAdapter build() {
+      return new JacksonAdapter(serializeNulls, serializeEmpty, failOnUnknown, jsonFactory);
+    }
+  }
+
   private final JsonFactory jsonFactory;
   private final boolean serializeNulls;
   private final boolean serializeEmpty;
@@ -47,6 +97,24 @@ public JacksonAdapter(boolean serializeNulls, boolean serializeEmpty, boolean fa
     this.jsonFactory = jsonFactory;
   }
 
+  /**
+   * Return a new builder to create a JacksonAdapter.
+   *
+   * <pre>{@code
+   *
+   * JsonFactory customFactory = ...;
+   *
+   * var jacksonAdapter = JacksonAdapter.newBuilder()
+   *   .serializeNulls(true)
+   *   .jsonFactory(customFactory)
+   *   .build();
+   *
+   * }</pre>
+   */
+  public static Builder newBuilder() {
+    return new Builder();
+  }
+
   @Override
   public PropertyNames properties(String... names) {
     return new JacksonNames(names);

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

@@ -25,7 +25,9 @@ class JacksonAdapterTest {
   @Test
   void custom_JsonFactory() {
 
-    JacksonAdapter jacksonAdapter = new JacksonAdapter(false, false, false, HUMAN_READABLE_JSON_FACTORY);
+    JacksonAdapter jacksonAdapter = JacksonAdapter.newBuilder()
+      .jsonFactory(HUMAN_READABLE_JSON_FACTORY)
+      .build();
 
     Jsonb jsonb = Jsonb.newBuilder()
       .adapter(jacksonAdapter)