Implement a custom record extractor debugger.

cobol-parser/src/test/scala/za/co/absa/cobrix/cobol/mock/CustomRecordExtractorMock.scala

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+/*
+ * Copyright 2018 ABSA Group Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package za.co.absa.cobrix.cobol.mock
+
+import za.co.absa.cobrix.cobol.reader.extractors.raw.{RawRecordContext, RawRecordExtractor}
+
+/**
+  * This is a record extractor for a binary file where
+  * - even records have the size of 2 bytes.
+  * - odd records have the size of 3 bytes.
+  */
+class CustomRecordExtractorMock(ctx: RawRecordContext) extends Serializable with RawRecordExtractor {
+  CustomRecordExtractorMock.additionalInfo = ctx.additionalInfo
+  CustomRecordExtractorMock.catchContext = ctx
+
+  private var recordNumber = ctx.startingRecordNumber
+
+  override def offset: Long = ctx.inputStream.offset
+
+  override def hasNext: Boolean = !ctx.inputStream.isEndOfStream
+
+  @throws[NoSuchElementException]
+  override def next(): Array[Byte] = {
+    if (!hasNext) {
+      throw new NoSuchElementException
+    }
+
+    val rawRecord = if (recordNumber % 2 == 0) {
+      ctx.inputStream.next(2)
+    } else {
+      ctx.inputStream.next(3)
+    }
+
+    recordNumber += 1
+
+    rawRecord
+  }
+}
+
+object CustomRecordExtractorMock {
+  var additionalInfo: String = ""
+  var catchContext: RawRecordContext = _
+}

cobol-parser/src/test/scala/za/co/absa/cobrix/cobol/reader/RecordExtractorDebugSpec.scala

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+/*
+ * Copyright 2018 ABSA Group Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package za.co.absa.cobrix.cobol.reader
+
+import org.scalatest.wordspec.AnyWordSpec
+import org.slf4j.LoggerFactory
+import za.co.absa.cobrix.cobol.mock.CustomRecordExtractorMock
+import za.co.absa.cobrix.cobol.reader.extractors.raw.RawRecordContext
+import za.co.absa.cobrix.cobol.reader.memorystream.TestStringStream
+
+class RecordExtractorDebugSpec extends AnyWordSpec {
+  private val log = LoggerFactory.getLogger("debug")
+
+  private val data = "AABBBCCDDDEEFFF"
+
+  // This is a code snippet that can be used to test custom record extractors
+  "record extractor data should be extracted as expected" in {
+    val dataStream = new TestStringStream(data)
+    val headerStream = new TestStringStream(data)
+
+    val ctx = RawRecordContext(0, dataStream, headerStream, null, null, null, "")
+    val extractor = new CustomRecordExtractorMock(ctx)
+
+    var i = 0
+    log.info(s"${headerStream.offset} : headers")
+
+    while (extractor.hasNext) {
+      val offset = dataStream.offset
+      val record = extractor.next()
+      val recordHex = record.map(b => f"$b%02X").mkString.take(10)
+      log.info(s"$offset : ${record.length} : $recordHex")
+      i += 1
+    }
+
+    assert(i == 6)
+  }
+}