updated json iterators

json/README.md

@@ -36,10 +36,10 @@ and `2.13`
         * `timestamp-millis`
         * `timestamp-micros`
 
-### [JsonArrayIterator](src/main/scala/io/github/agolovenko/avro/json/JsonArrayIterator.scala)
-* A utility class that implements `Iterator[JsObject]` and parses array of objects in stream-like fashion
+### [JsonIterator](src/main/scala/io/github/agolovenko/avro/json/JsonIterator.scala)
+* A utility class that implements `Iterator[JsObject]` and parses an array of objects or a single object in stream-like fashion
 
-### [JsonLIterator](src/main/scala/io/github/agolovenko/avro/json/JsonLIterator.scala)
+### [JsonLinesIterator](src/main/scala/io/github/agolovenko/avro/json/JsonLinesIterator.scala)
 * A utility class that implements `Iterator[JsObject]` and parses `JsonL` format in stream-like fashion
 
 ## Usage

json/src/main/scala/io/github/agolovenko/avro/json/JsonException.scala

@@ -0,0 +1,5 @@
+package io.github.agolovenko.avro.json
+
+import scala.util.control.NoStackTrace
+
+class JsonException(message: String, cause: Throwable = null) extends RuntimeException(message, cause) with NoStackTrace

json/src/main/scala/io/github/agolovenko/avro/json/JsonArrayIterator.scala → json/src/main/scala/io/github/agolovenko/avro/json/JsonIterator.scala

@@ -1,34 +1,34 @@
 package io.github.agolovenko.avro.json
 
-import com.fasterxml.jackson.core.{JsonParser => JJsonParser, JsonToken}
+import com.fasterxml.jackson.core.{JsonToken, JsonParser => JJsonParser}
 import com.fasterxml.jackson.databind.ObjectMapper
 import com.fasterxml.jackson.databind.node.ObjectNode
 import play.api.libs.json.jackson.PlayJsonModule
 import play.api.libs.json.{JsObject, JsonParserSettings}
 
 import java.io.Reader
 
-class JsonArrayIterator(reader: => Reader) extends Iterator[JsObject] {
+class JsonIterator(reader: => Reader) extends Iterator[JsObject] {
   private val mapper = new ObjectMapper()
     .registerModule(new PlayJsonModule(JsonParserSettings()))
     .enable(JJsonParser.Feature.AUTO_CLOSE_SOURCE)
 
   private val parser         = mapper.createParser(reader)
   private val jsObjectReader = mapper.readerFor(classOf[JsObject])
 
-  private var nextToken = {
-    val next = parser.nextToken
-    if (next != JsonToken.START_ARRAY) throw new IllegalStateException(s"Expected start of array, got instead: $next")
-
-    parser.nextToken
+  private var nextToken = parser.nextToken match {
+    case JsonToken.START_ARRAY  => parser.nextToken
+    case JsonToken.START_OBJECT => JsonToken.START_OBJECT
+    case next                   => throw new JsonException(s"Expected start of an array or an object, got instead: $next")
   }
 
-  override def hasNext: Boolean =
-    if (nextToken == JsonToken.START_OBJECT) true
-    else if (nextToken == JsonToken.END_ARRAY) {
+  override def hasNext: Boolean = nextToken match {
+    case JsonToken.START_OBJECT => true
+    case JsonToken.END_ARRAY | null =>
       parser.close()
       false
-    } else throw new IllegalStateException(s"Expected end of array, got instead: $nextToken")
+    case next => throw new JsonException(s"Expected end of an array or an object, got instead: $next")
+  }
 
   override def next(): JsObject = {
     val objectNode = mapper.readTree[ObjectNode](parser)

json/src/main/scala/io/github/agolovenko/avro/json/JsonLIterator.scala → json/src/main/scala/io/github/agolovenko/avro/json/JsonLinesIterator.scala

@@ -4,7 +4,7 @@ import play.api.libs.json.{JsObject, Json}
 
 import java.io.{BufferedReader, Reader}
 
-class JsonLIterator(reader: => Reader) extends Iterator[JsObject] {
+class JsonLinesIterator(reader: => Reader) extends Iterator[JsObject] {
   private val bufferedReader = reader match {
     case buffered: BufferedReader => buffered
     case unBuffered               => new BufferedReader(unBuffered)

json/src/test/scala/io/github/agolovenko/avro/json/JsonIteratorSpec.scala

@@ -0,0 +1,68 @@
+package io.github.agolovenko.avro.json
+
+import org.scalatest.matchers.should.Matchers
+import org.scalatest.wordspec.AnyWordSpec
+
+import java.io.StringReader
+
+class JsonIteratorSpec extends AnyWordSpec with Matchers {
+  "parses json array" in {
+    val json =
+      """
+        |[
+        |  {
+        |    "lastUpdated": "2020-04-17T19:38:47.04+00:00",
+        |    "id": "16289",
+        |    "clientId": 123,
+        |    "description": {
+        |      "type": "normal",
+        |      "text": "good one"
+        |    }
+        |  },
+        |  {
+        |    "lastUpdated": "2020-04-17T19:38:40.04+00:00",
+        |    "id": "16288",
+        |    "clientId": 124,
+        |    "description": {
+        |      "type": "normal",
+        |      "text": "very good one"
+        |    }
+        |  }
+        |]
+        |""".stripMargin
+
+    val it        = new JsonIterator(new StringReader(json))
+    val jsObjects = it.toList
+
+    jsObjects should have size 2
+    (jsObjects(1) \ "clientId").as[Int] shouldBe 124
+  }
+
+  "parses json object" in {
+    val json =
+      """
+        |  {
+        |    "lastUpdated": "2020-04-17T19:38:47.04+00:00",
+        |    "id": "16289",
+        |    "clientId": 123,
+        |    "description": {
+        |      "type": "normal",
+        |      "text": "good one"
+        |    }
+        |  }
+        |""".stripMargin
+
+    val it        = new JsonIterator(new StringReader(json))
+    val jsObjects = it.toList
+
+    jsObjects should have size 1
+    (jsObjects.head \ "clientId").as[Int] shouldBe 123
+  }
+
+  "expects array of objects as input" in {
+    an[JsonException] should be thrownBy new JsonIterator(new StringReader(" [{}, 1234]")).foreach(_ => ())
+
+    noException should be thrownBy new JsonIterator(new StringReader(" {}")).foreach(_ => ())
+    noException should be thrownBy new JsonIterator(new StringReader(""" [{}, {"number": 1234}  ]""")).foreach(_ => ())
+  }
+}

json/src/test/scala/io/github/agolovenko/avro/json/JsonLIteratorSpec.scala → json/src/test/scala/io/github/agolovenko/avro/json/JsonLinesIteratorSpec.scala

@@ -5,7 +5,7 @@ import org.scalatest.wordspec.AnyWordSpec
 
 import java.io.StringReader
 
-class JsonLIteratorSpec extends AnyWordSpec with Matchers {
+class JsonLinesIteratorSpec extends AnyWordSpec with Matchers {
   "parses jsonL" in {
     val json =
       """
@@ -16,19 +16,19 @@ class JsonLIteratorSpec extends AnyWordSpec with Matchers {
         |
         |""".stripMargin
 
-    val it        = new JsonLIterator(new StringReader(json))
-    val jsObjects = it.toList
+    val it        = new JsonLinesIterator(new StringReader(json))
+    val jsObjects = it.toVector
 
     jsObjects should have size 2
     (jsObjects(1) \ "clientId").as[Int] shouldBe 124
   }
 
   "accepts empty input" in {
-    noException should be thrownBy new JsonLIterator(new StringReader("   ")).foreach(_ => ())
+    noException should be thrownBy new JsonLinesIterator(new StringReader("   ")).foreach(_ => ())
   }
 
   "expects jsonL as input" in {
-    an[Exception] should be thrownBy new JsonLIterator(new StringReader("[{}]")).foreach(_ => ())
-    noException should be thrownBy new JsonLIterator(new StringReader("{}\n\n{}")).foreach(_ => ())
+    an[Exception] should be thrownBy new JsonLinesIterator(new StringReader("[{}]")).foreach(_ => ())
+    noException should be thrownBy new JsonLinesIterator(new StringReader("{}\n\n{}")).foreach(_ => ())
   }
 }