Java object diff testing

DiffTesting.java

import java.util.Arrays;
import java.util.List;

import org.javers.core.Javers;
import org.javers.core.JaversBuilder;
import org.javers.core.MappingStyle;
import org.javers.core.changelog.SimpleTextChangeLog;
import org.javers.core.diff.Change;
import org.javers.core.metamodel.object.InstanceIdDTO;
import org.junit.Test;

import de.danielbechler.diff.ObjectDifferBuilder;
import de.danielbechler.diff.node.DiffNode;
import de.danielbechler.diff.node.DiffNode.Visitor;
import de.danielbechler.diff.node.Visit;

public class DiffTesting {

    private class TestObject {

        private Integer _id;
        private String _name;
        private List<String> _tags;
        private List<List<String>> _table;

        TestObject(Integer id) {
            _id = id;
        }

        public Integer getId() {
            return _id;
        }

        public void setId(Integer id) {
            _id = id;
        }

        public String getName() {
            return _name;
        }

        public void setName(String name) {
            _name = name;
        }

        public List<List<String>> getTable() {
            return _table;
        }

        public void setTable(List<List<String>> table) {
            _table = table;
        }

        public List<String> getTags() {
            return _tags;
        }

        public void setTags(List<String> tags) {
            _tags = tags;
        }
    }

    @Test
    public void testJavers() {
        Javers javers = JaversBuilder.javers().withMappingStyle(MappingStyle.FIELD).registerEntity(TestObject.class, "_id").build();

        TestObject base = new TestObject(1);
        base.setName("A Name");
        base.setTable(Arrays.asList(Arrays.asList("A", "B", "C"), Arrays.asList("D", "E", "F")));

        javers.commit("me@here.com", base);

        base.setName("A Different Name");
        base.setTags(Arrays.asList("tag1", "tag2"));
        base.setTable(Arrays.asList(Arrays.asList("A", "B", "C"), Arrays.asList("X", "Y", "Z")));

        javers.commit("me@here.com", base);

        // list out changes
        List<Change> changes = javers.getChangeHistory(InstanceIdDTO.instanceId(1, TestObject.class), 5);
        SimpleTextChangeLog log = new SimpleTextChangeLog();
        javers.processChangeList(changes, log);
        System.out.println(log.result());

    }

    @Test
    public void testJavaObjectDiff() {
        final TestObject base = new TestObject(1);
        base.setName("A Name");
        base.setTable(Arrays.asList(Arrays.asList("A", "B", "C"), Arrays.asList("D", "E", "F")));

        final TestObject working = new TestObject(1);
        working.setName("A Different Name");
        working.setTags(Arrays.asList("tag1", "tag2"));
        working.setTable(Arrays.asList(Arrays.asList("A", "B", "C"), Arrays.asList("X", "Y", "Z")));

        DiffNode diff = ObjectDifferBuilder.buildDefault().compare(working, base);
        diff.visit(new Visitor() {
            @Override
            public void node(DiffNode node, Visit visit) {
                Object baseValue = node.canonicalGet(base);
                Object workingValue = node.canonicalGet(working);
                String message = node.getPath() + " changed from " + baseValue + " to " + workingValue;
                System.out.println(message);
            }
        });
    }

}