add extra convenience method to generated builder

* takes a lambda that gets a builder to modify
* makes it possible to get rid of some boilerplate code
  as you don't have to "new" the inner builder on the outside.

2 files changed, 48 insertions, 0 deletions

diff --git a/configgen/src/main/java/com/yahoo/config/codegen/BuilderGenerator.java b/configgen/src/main/java/com/yahoo/config/codegen/BuilderGenerator.java
index 548bd14ccb3..bbbb8676e3f 100644
--- a/configgen/src/main/java/com/yahoo/config/codegen/BuilderGenerator.java
+++ b/configgen/src/main/java/com/yahoo/config/codegen/BuilderGenerator.java
@@ -157,6 +157,18 @@ public class BuilderGenerator {
                     "}\n" + //
                     "\n" + //
                     "/**\n" + //
+                    " * Make a new builder and run the supplied function on it before adding it to the list\n" + //
+                    " * @param __func lambda that modifies the given builder\n" + //
+                    " * @return this builder\n" + //
+                    " */\n" + //
+                    "public Builder " + n.getName() + "(java.util.function.Consumer<" + builderType(n) + "> __func) {\n" + //
+                    "  " + builderType(n) + " __inner = new " + builderType(n) +"();\n" + //
+                    "  __func.accept(__inner);\n" + //
+                    "  " + n.getName() + ".add(__inner);\n" + //
+                    "  return this;\n" + //
+                    "}\n" + //
+                    "\n" + //
+                    "/**\n" + //
                     " * Set the given list as this builder's list of " + nodeClass(n) + " builders\n" + //
                     " * @param __builders a list of builders\n" + //
                     " * @return this builder\n" + //
diff --git a/configgen/src/test/resources/allfeatures.reference b/configgen/src/test/resources/allfeatures.reference
index e0b6176efa2..08d8aa122c9 100644
--- a/configgen/src/test/resources/allfeatures.reference
+++ b/configgen/src/test/resources/allfeatures.reference
@@ -582,6 +582,18 @@ public final class AllfeaturesConfig extends ConfigInstance {
     }
 
     /**
+     * Make a new builder and run the supplied function on it before adding it to the list
+     * @param __func lambda that modifies the given builder
+     * @return this builder
+     */
+    public Builder myArray(java.util.function.Consumer<MyArray.Builder> __func) {
+      MyArray.Builder __inner = new MyArray.Builder();
+      __func.accept(__inner);
+      myArray.add(__inner);
+      return this;
+    }
+
+    /**
      * Set the given list as this builder's list of MyArray builders
      * @param __builders a list of builders
      * @return this builder
@@ -1616,6 +1628,18 @@ public final class AllfeaturesConfig extends ConfigInstance {
       }
 
       /**
+       * Make a new builder and run the supplied function on it before adding it to the list
+       * @param __func lambda that modifies the given builder
+       * @return this builder
+       */
+      public Builder anotherArray(java.util.function.Consumer<AnotherArray.Builder> __func) {
+        AnotherArray.Builder __inner = new AnotherArray.Builder();
+        __func.accept(__inner);
+        anotherArray.add(__inner);
+        return this;
+      }
+
+      /**
        * Set the given list as this builder's list of AnotherArray builders
        * @param __builders a list of builders
        * @return this builder
@@ -1914,6 +1938,18 @@ public final class AllfeaturesConfig extends ConfigInstance {
       }
 
       /**
+       * Make a new builder and run the supplied function on it before adding it to the list
+       * @param __func lambda that modifies the given builder
+       * @return this builder
+       */
+      public Builder anotherArray(java.util.function.Consumer<AnotherArray.Builder> __func) {
+        AnotherArray.Builder __inner = new AnotherArray.Builder();
+        __func.accept(__inner);
+        anotherArray.add(__inner);
+        return this;
+      }
+
+      /**
        * Set the given list as this builder's list of AnotherArray builders
        * @param __builders a list of builders
        * @return this builder