From 1fce1453294f9647178e67849629642be88b57f2 Mon Sep 17 00:00:00 2001
From: Dai MIKURUBE <dmikurube@acm.org>
Date: Fri, 18 Aug 2023 16:40:27 +0900
Subject: [PATCH] [WIP] Implement flattening JSON Arrays

---
 .../org/embulk/util/json/JsonValueParser.java  | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/main/java/org/embulk/util/json/JsonValueParser.java b/src/main/java/org/embulk/util/json/JsonValueParser.java
index 8cfa727..5a4bf8b 100644
--- a/src/main/java/org/embulk/util/json/JsonValueParser.java
+++ b/src/main/java/org/embulk/util/json/JsonValueParser.java
@@ -34,6 +34,7 @@
 public final class JsonValueParser implements Closeable {
     private JsonValueParser(
             final com.fasterxml.jackson.core.JsonParser jacksonParser,
+            final int depthToFlattenJsonArrays,
             final boolean hasLiteralsWithNumbers,
             final boolean hasFallbacksForUnparsableNumbers,
             final double defaultDouble,
@@ -41,6 +42,7 @@ private JsonValueParser(
         this.jacksonParser = Objects.requireNonNull(jacksonParser);
         this.valueReader = new InternalJsonValueReader(
                 hasLiteralsWithNumbers, hasFallbacksForUnparsableNumbers, defaultDouble, defaultLong);
+        this.depthToFlattenJsonArrays = depthToFlattenJsonArrays;
         this.hasLiteralsWithNumbers = hasLiteralsWithNumbers;
         this.hasFallbacksForUnparsableNumbers = hasFallbacksForUnparsableNumbers;
         this.defaultDouble = defaultDouble;
@@ -54,6 +56,7 @@ public static final class Builder {
         Builder(final JsonFactory factory) {
             this.factory = Objects.requireNonNull(factory);
             this.root = null;
+            this.depthToFlattenJsonArrays = 0;
             this.hasLiteralsWithNumbers = false;
             this.hasFallbacksForUnparsableNumbers = false;
             this.defaultDouble = 0.0;
@@ -84,6 +87,17 @@ public Builder root(final String root) {
             return this;
         }
 
+        /**
+         * Sets the depth to flatten JSON Arrays to parse.
+         *
+         * @param depthToFlattenJsonArrays  the depth to flatten JSON Arrays
+         * @return this builder
+         */
+        public Builder setDepthToFlattenJsonArrays(final int depthToFlattenJsonArrays) {
+            this.depthToFlattenJsonArrays = depthToFlattenJsonArrays;
+            return this;
+        }
+
         /**
          * Enables creating {@link JsonDouble} and {@link JsonLong} instances with supplemental literal strings.
          *
@@ -126,6 +140,7 @@ public Builder fallbackForUnparsableNumbers(final double defaultDouble, final lo
         public JsonValueParser build(final String json) throws IOException {
             return new JsonValueParser(
                     buildJacksonParser(json),
+                    this.depthToFlattenJsonArrays,
                     this.hasLiteralsWithNumbers,
                     this.hasFallbacksForUnparsableNumbers,
                     this.defaultDouble,
@@ -141,6 +156,7 @@ public JsonValueParser build(final String json) throws IOException {
         public JsonValueParser build(final InputStream jsonStream) throws IOException {
             return new JsonValueParser(
                     buildJacksonParser(jsonStream),
+                    this.depthToFlattenJsonArrays,
                     this.hasLiteralsWithNumbers,
                     this.hasFallbacksForUnparsableNumbers,
                     this.defaultDouble,
@@ -170,6 +186,7 @@ private com.fasterxml.jackson.core.JsonParser extendJacksonParser(final com.fast
         private final JsonFactory factory;
 
         private JsonPointer root;
+        private int depthToFlattenJsonArrays;
         private boolean hasLiteralsWithNumbers;
         private boolean hasFallbacksForUnparsableNumbers;
         private double defaultDouble;
@@ -243,6 +260,7 @@ public final void close() throws IOException {
     private final com.fasterxml.jackson.core.JsonParser jacksonParser;
     private final InternalJsonValueReader valueReader;
 
+    private final int depthToFlattenJsonArrays;
     private final boolean hasLiteralsWithNumbers;
     private final boolean hasFallbacksForUnparsableNumbers;
     private final double defaultDouble;