content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.kafka.common.header.internals;
  
  import org.apache.kafka.common.header.Header;
  import org.apache.kafka.common.header.Headers;
  
  import org.junit.jupiter.api.Test;
  
  import java.io.IOException;
  import java.util.Iterator;
  
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  import static org.junit.jupiter.api.Assertions.fail;
  
  public class RecordHeadersTest {
  
      @Test
      public void testAdd() {
          Headers headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
  
          Header header = headers.iterator().next();
          assertHeader("key", "value", header);
  
          headers.add(new RecordHeader("key2", "value2".getBytes()));
  
          assertHeader("key2", "value2", headers.lastHeader("key2"));
          assertEquals(2, getCount(headers));
      }
  
      @Test
      public void testRemove() {
          Headers headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
  
          assertTrue(headers.iterator().hasNext());
  
          headers.remove("key");
  
          assertFalse(headers.iterator().hasNext());
      }
  
      @Test
      public void testAddRemoveInterleaved() {
          Headers headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
          headers.add(new RecordHeader("key2", "value2".getBytes()));
  
          assertTrue(headers.iterator().hasNext());
  
          headers.remove("key");
  
          assertEquals(1, getCount(headers));
  
          headers.add(new RecordHeader("key3", "value3".getBytes()));
          
          assertNull(headers.lastHeader("key"));
  
          assertHeader("key2", "value2", headers.lastHeader("key2"));
  
          assertHeader("key3", "value3", headers.lastHeader("key3"));
  
          assertEquals(2, getCount(headers));
  
          headers.remove("key2");
  
          assertNull(headers.lastHeader("key"));
  
          assertNull(headers.lastHeader("key2"));
  
          assertHeader("key3", "value3", headers.lastHeader("key3"));
  
          assertEquals(1, getCount(headers));
  
          headers.add(new RecordHeader("key3", "value4".getBytes()));
  
          assertHeader("key3", "value4", headers.lastHeader("key3"));
  
          assertEquals(2, getCount(headers));
  
          headers.add(new RecordHeader("key", "valueNew".getBytes()));
  
          assertEquals(3, getCount(headers));
  
  
          assertHeader("key", "valueNew", headers.lastHeader("key"));
  
          headers.remove("key3");
  
          assertEquals(1, getCount(headers));
  
          assertNull(headers.lastHeader("key2"));
  
          headers.remove("key");
  
          assertFalse(headers.iterator().hasNext());
      }
  
      @Test
      public void testLastHeader() {
          Headers headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
          headers.add(new RecordHeader("key", "value2".getBytes()));
          headers.add(new RecordHeader("key", "value3".getBytes()));
  
          assertHeader("key", "value3", headers.lastHeader("key"));
          assertEquals(3, getCount(headers));
  
      }
  
      @Test
      public void testReadOnly() {
          RecordHeaders headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
          Iterator<Header> headerIteratorBeforeClose = headers.iterator();
          headers.setReadOnly();
          try {
              headers.add(new RecordHeader("key", "value".getBytes()));
              fail("IllegalStateException expected as headers are closed");
          } catch (IllegalStateException ise) {
              //expected  
          }
  
          try {
              headers.remove("key");
              fail("IllegalStateException expected as headers are closed");
          } catch (IllegalStateException ise) {
              //expected  
          }
  
          try {
              Iterator<Header> headerIterator = headers.iterator();
              headerIterator.next();
              headerIterator.remove();
              fail("IllegalStateException expected as headers are closed");
          } catch (IllegalStateException ise) {
              //expected  
          }
          
          try {
              headerIteratorBeforeClose.next();
              headerIteratorBeforeClose.remove();
              fail("IllegalStateException expected as headers are closed");
          } catch (IllegalStateException ise) {
              //expected  
          }
      }
  
      @Test
      public void testHeaders() throws IOException {
          RecordHeaders headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
          headers.add(new RecordHeader("key1", "key1value".getBytes()));
          headers.add(new RecordHeader("key", "value2".getBytes()));
          headers.add(new RecordHeader("key2", "key2value".getBytes()));
  
  
          Iterator<Header> keyHeaders = headers.headers("key").iterator();
          assertHeader("key", "value", keyHeaders.next());
          assertHeader("key", "value2", keyHeaders.next());
          assertFalse(keyHeaders.hasNext());
  
          keyHeaders = headers.headers("key1").iterator();
          assertHeader("key1", "key1value", keyHeaders.next());
          assertFalse(keyHeaders.hasNext());
  
          keyHeaders = headers.headers("key2").iterator();
          assertHeader("key2", "key2value", keyHeaders.next());
          assertFalse(keyHeaders.hasNext());
  
      }
  
      @Test
      public void testNew() {
          RecordHeaders headers = new RecordHeaders();
          headers.add(new RecordHeader("key", "value".getBytes()));
          headers.setReadOnly();
  
          RecordHeaders newHeaders = new RecordHeaders(headers);
          newHeaders.add(new RecordHeader("key", "value2".getBytes()));
  
          //Ensure existing headers are not modified
          assertHeader("key", "value", headers.lastHeader("key"));
          assertEquals(1, getCount(headers));
  
          //Ensure new headers are modified
          assertHeader("key", "value2", newHeaders.lastHeader("key"));
          assertEquals(2, getCount(newHeaders));
      }
  
      @Test
      public void shouldThrowNpeWhenAddingNullHeader() {
          final RecordHeaders recordHeaders = new RecordHeaders();
          assertThrows(NullPointerException.class, () -> recordHeaders.add(null));
      }
  
      @Test
      public void shouldThrowNpeWhenAddingCollectionWithNullHeader() {
          assertThrows(NullPointerException.class, () -> new RecordHeaders(new Header[1]));
      }
  
      private int getCount(Headers headers) {
          return headers.toArray().length;
      }
      
      static void assertHeader(String key, String value, Header actual) {
          assertEquals(key, actual.key());
          assertArrayEquals(value.getBytes(), actual.value());
      }
  
  }
  