Very simple Camel Bindy JUnit test with for fixed length record with a link in the middle. I started with the BindySimpleFixedLengthHeaderFooterTest but made this a lot simplier. Note that the test only does unmarshalling

BindySimpleFixedLengthWithLinkTest

/**
 * 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
 *
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 * 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.camel.dataformat.bindy.fixed;

import org.apache.camel.EndpointInject;
import org.apache.camel.Exchange;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.component.mock.MockEndpoint;
import org.apache.camel.dataformat.bindy.annotation.DataField;
import org.apache.camel.dataformat.bindy.annotation.FixedLengthRecord;
import org.apache.camel.dataformat.bindy.annotation.Link;
import org.apache.camel.model.dataformat.BindyDataFormat;
import org.apache.camel.model.dataformat.BindyType;
import org.apache.camel.test.junit4.CamelTestSupport;
import org.junit.Test;

/**
 * This test validates that header and footer records are successfully
 * marshalled / unmarshalled in conjunction with the primary data records
 * defined for the bindy data format.
 */
public class BindySimpleFixedLengthWithLinkTest extends CamelTestSupport {

  public static final String URI_DIRECT_UNMARSHALL = "direct:unmarshall";
	public static final String URI_MOCK_UNMARSHALL_RESULT = "mock:unmarshall-result";

	private static final String TEST_RECORD = "AAABBBCCC\r\n";

	@EndpointInject(uri = URI_MOCK_UNMARSHALL_RESULT)
	private MockEndpoint unmarshallResult;

	// *************************************************************************
	// TESTS
	// *************************************************************************

	@Test
	public void testUnmarshallMessage() throws Exception {

		unmarshallResult.expectedMessageCount(1);

		template.sendBody(URI_DIRECT_UNMARSHALL, TEST_RECORD);

		unmarshallResult.assertIsSatisfied();

		// check the model
		Exchange exchange = unmarshallResult.getReceivedExchanges().get(0);
		Order order = (Order) exchange.getIn().getBody();
		assertEquals("AAA", order.fieldA);
		assertEquals("BBB", order.subRec.fieldB);
		assertEquals("CCC", order.fieldC);

	}

	// *************************************************************************
	// ROUTES
	// *************************************************************************

	@Override
	protected RouteBuilder createRouteBuilder() throws Exception {
		RouteBuilder routeBuilder = new RouteBuilder() {

			@Override
			public void configure() throws Exception {
				BindyDataFormat bindy = new BindyDataFormat();
				bindy.setClassType(Order.class);
				bindy.setLocale("en");
				bindy.setType(BindyType.Fixed);

				from(URI_DIRECT_UNMARSHALL).unmarshal()
						.bindy(BindyType.Fixed, Order.class)
						.to(URI_MOCK_UNMARSHALL_RESULT);
			}
		};

		return routeBuilder;
	}

	// *************
	// DATA FORMATS
	// *************
	@FixedLengthRecord
	public static class Order {
		// 'AAA'
		@DataField(pos = 1, position = 1, length = 3)
		private String fieldA;

		@Link
		private SubRec subRec;

		// 'CCC'
		@DataField(pos = 3, position = 3, length = 3)
		private String fieldC;

		public String getFieldA() {
			return fieldA;
		}

		public void setFieldA(String fieldA) {
			this.fieldA = fieldA;
		}

		public String getFieldC() {
			return fieldC;
		}

		public void setFieldC(String fieldC) {
			this.fieldC = fieldC;
		}

		public SubRec getSubRec() {
			return subRec;
		}

		public void setSubRec(SubRec subRec) {
			this.subRec = subRec;
		}

	}

	@Link
	@FixedLengthRecord
	public static class SubRec {

		@DataField(pos = 2, position = 2, length = 3)
		private String fieldB;

		public String getFieldB() {
			return fieldB;
		}

		public void setFieldB(String fieldB) {
			this.fieldB = fieldB;
		}

	}
}