target.setDescription( "TARGET" );

        Model source = new Model();
        source.setDescription( "SOURCE" );

        modelMerger.merge( target, source, true, null );
        assertThat( target.getDescription(), is( "SOURCE" ) );

        target.setDescription( "TARGET" );
        modelMerger.merge( target, source, false, null );
        assertThat( target.getDescription(), is( "TARGET" ) );
    }

## Overview

Replication relies on immutability provided by versioning to sync objects between the configured source and replication target. Replication results in the object data, metadata, last modification time and version ID all being identical between the source and target. Thus version ordering is automatically guaranteed on the source and target clusters.

### Replication of object version and metadata

            result.setLanguages(DfTypeUtil.toString(source.get("languages")));
            result.setQueryId(DfTypeUtil.toString(source.get("queryId")));
            result.setQueryOffset(DfTypeUtil.toInteger(source.get("queryOffset")));
            result.setQueryPageSize(DfTypeUtil.toInteger(source.get("queryPageSize")));
            result.setQueryTime(DfTypeUtil.toLong(source.get("queryTime")));

    }
  }

  /**
   * Returns the trailers. It is only safe to call this once the source stream has been completely
   * exhausted.
   */
  @Throws(IOException::class)
  fun trailers(): Headers {
    this.withLock {
      if (source.finished && source.receiveBuffer.exhausted() && source.readBuffer.exhausted()) {
        return source.trailers ?: EMPTY_HEADERS
      }
      if (errorCode != null) {

        int count = 0;
        Set<String> valueSet = Collections.synchronizedSet(new HashSet<>());
        Map<String, Object> source;
        while ((source = reader.read()) != null) {
            assertTrue(source.get("field1").toString().startsWith("test"));
            valueSet.add(source.get("field1").toString());
            count++;
        }
        assertEquals(num, count);
        assertEquals(num, valueSet.size());

        source.put("aaa", "");
        source.put("bbb", "a");
        assertFalse(fessConfig.validateIndexRequiredFields(source));
        source.put("aaa", " ");
        source.put("bbb", "a");
        assertFalse(fessConfig.validateIndexRequiredFields(source));
        source.put("aaa", "a");
        source.put("bbb", "a");

      return responseBody.contentLength();
    }

    @Override public BufferedSource source() {
      if (bufferedSource == null) {
        bufferedSource = Okio.buffer(source(responseBody.source()));
      }
      return bufferedSource;
    }

    private Source source(Source source) {
      return new ForwardingSource(source) {
        long totalBytesRead = 0L;

        expect:
        parse(source) == transformed

        where:
        source         | transformed
        "<p>text"      | "<p>text</p>"
        "<ul><li>text" | "<ul><li>text</li></ul>"
    }

    def "adds implicit end of element"() {
        expect:
        parse(source) == transformed

        where:
        source                                    | transformed

            result.setCreatedTime(DfTypeUtil.toLong(source.get("createdTime")));
            result.setDepth(DfTypeUtil.toInteger(source.get("depth")));
            result.setDescription(DfTypeUtil.toString(source.get("description")));
            result.setExcludedDocPaths(DfTypeUtil.toString(source.get("excludedDocPaths")));
            result.setExcludedPaths(DfTypeUtil.toString(source.get("excludedPaths")));

    assertEquals(testString.length() * 3, result.length());
  }

  public void testReady() throws Exception {
    CharSource source = newCharSource("a");
    Iterable<? extends CharSource> list = ImmutableList.of(source, source);
    Reader joinedReader = CharSource.concat(list).openStream();

    assertTrue(joinedReader.ready());
    assertEquals('a', joinedReader.read());