Cannot resolve JacksonTableTransformer for Cucumber 4.x.x

Question

Following this example, I am converting Cucumber 3.x.x datatable configurer to Cucumber 4.2.0 using JacksonTableTransformer but is saying it cannot be resolved to a type.

Feature

And I Enter My Regular Income Sources
    | name      | Salary        |
    | amount    | 25000         |
    | frequency | every 2 weeks |
And I Enter My Regular Expenses
    | name        | amount | frequency     |
    | Electricity | 5500   | Monthly       |
    | Water       | 900    | Weekly        |
    | Internet    | 1900   | Every 2 Weeks |
    | Cable TV    | 555    | Daily         |

Configurer

import io.cucumber.datatable.dependency.com.fasterxml.jackson.databind.ObjectMapper;

public class Configurer implements TypeRegistryConfigurer {

    @Override
    public Locale locale() {
        return Locale.ENGLISH;
    }

    @Override
    public void configureTypeRegistry(TypeRegistry registry) {

        // Just added these 2 lines for Cucumber 4.2.0
        JacksonTableTransformer jacksonTableTransformer = new JacksonTableTransformer();
        registry.setDefaultDataTableEntryTransformer(jacksonTableTransformer);

        /*
         * Maps DataTable with header row to multiple objects of Type<T>. Each row below
         * the header is an object.
         */
        registry.defineDataTableType(new DataTableType(Transaction.class, new TableEntryTransformer<Transaction>() {
            @Override
            public Transaction transform(Map<String, String> entry) {
                return new Transaction(entry);
            }
        }));

        /*
         * Maps DataTable with label column to a single object of Type<T>. Left column
         * is field name, right column is value.
         */
        registry.defineDataTableType(new DataTableType(Transaction.class, new TableTransformer<Transaction>() {
            @Override
            public Transaction transform(DataTable table) throws Throwable {
                return new Transaction(table.asMaps().get(0));
            }
        }));

    }

}

I only have 2 datatables and the configurer works for 3.x.x and 4.x.x if I remove the 2 lines added. I do want to use the object mapper though.

Answer 1

This worked but not exactly sure how. If anyone can add one-liner comments or drop an explanation it would be great for reference for everyone. Thanks!

Type

public class Transaction {

    private String name = null;
    private String amount = null;
    private String frequency = null;
    private String month = null;

    public Transaction() {
        // Empty constructor
    }

    public Transaction(Map<String, String> entry) {
        this.name = entry.get("name");
        this.amount = entry.get("amount");
        this.frequency = entry.get("frequency");
        this.month = entry.get("month");
    }

    // getters and setters
}

Feature

And I Enter My Regular Income Sources
    | name      | Salary        |
    | amount    | 25000         |
    | frequency | every 2 weeks |
And I Enter My Regular Expenses
    | name        | amount | frequency     |
    | Electricity | 5500   | Monthly       |
    | Water       | 900    | Weekly        |
    | Internet    | 1900   | Every 2 Weeks |
    | Cable TV    | 555    | Daily         |

StepDef

@When("I Enter My Regular Income Sources")
public void I_Enter_My_Regular_Income_Sources(@Transpose Transaction transaction) throws Throwable {
    // vertical datatable transforms to a single object
    // column 1 = field name, column 2 = value
}

@When("I Enter My Regular Expenses")
public void I_Enter_My_Regular_Expenses(DataTable table) throws Throwable {
    // datatable with header row transforms to a List of objects
    // 1 row = 1 object
    List<Transaction> transactions = table.asList(Transaction.class);   
}

Configurer

public class Configurer implements TypeRegistryConfigurer {

    @Override
    public Locale locale() {
        return Locale.ENGLISH;
    }

    @Override
    public void configureTypeRegistry(TypeRegistry registry) {

        JacksonTableTransformer jtt = new JacksonTableTransformer();
        registry.setDefaultParameterTransformer(jtt);
        registry.setDefaultDataTableCellTransformer(jtt);
        registry.setDefaultDataTableEntryTransformer(jtt);

        /*
         * Maps DataTable with label column to a single object of Type<T>. Left column
         * is field name, right column is value.
         */
        registry.defineDataTableType(new DataTableType(Transaction.class, new TableTransformer<Transaction>() {
            @Override
            public Transaction transform(DataTable table) throws Throwable {
                return new Transaction(table.asMaps().get(0));
            }
        }));

    }

    private static final class JacksonTableTransformer
            implements ParameterByTypeTransformer, TableCellByTypeTransformer, TableEntryByTypeTransformer {

        private final ObjectMapper objMapper = new ObjectMapper();

        @Override
        public Object transform(String fromValue, Type toValueType) throws Throwable {
            return objMapper.convertValue(fromValue, objMapper.constructType(toValueType));
        }

        @Override
        public <T> T transform(String value, Class<T> cellType) throws Throwable {
            return objMapper.convertValue(value, cellType);
        }

        @Override
        public <T> T transform(Map<String, String> entry, Class<T> type, TableCellByTypeTransformer cellTransformer)
                throws Throwable {
            return objMapper.convertValue(entry, type);
        }

    }

}

Answer 2

Following this example, I am converting Cucumber 3.x.x datatable configurer to Cucumber 4.2.0 using JacksonTableTransformer but is saying it cannot be resolved to a type.

If you read the full class file that you linked you'll find that JacksonTableTransformer is defined at line 99. I.e. you will have to define this class yourself.