Parameter types let you convert parameters from cucumber-expressions to objects. Data table and doc string types let you convert data tables and doc strings to objects. Like step definitions, type definitions are part of the glue. When placed on the glue path Cucumber will detect them automatically.

For example, the following class registers a custom “Author” data table type:

package com.example;

import io.cucumber.java.DataTableType;
import io.cucumber.java.en.Given;

import java.util.List;
import java.util.Map;

public class StepDefinitions {

    @DataTableType
    public Author authorEntry(Map<String, String> entry) {
        return new Author(
            entry.get("firstName"),
            entry.get("lastName"),
            entry.get("famousBook"));
    }

    @Given("There are my favorite authors")
    public void these_are_my_favourite_authors(List<Author> authors) {
        // step implementation
    }
}    

The parameter type example:

package com.example;

import io.cucumber.java.ParameterType;
import io.cucumber.java.en.Given;

public class StepDefinitions {

    @ParameterType(".*")
    public Book book(String bookName) {
    	return new Book(bookName);
    }	

    @Given("{book} is my favorite book")
    public void this_is_my_favorite_book(Book book) {
        // step implementation
    }
}

The docstring type example:

package com.example;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.cucumber.java.DocStringType;
import io.cucumber.java.en.Given;

public class StepsDefinitions {

    private static ObjectMapper objectMapper = new ObjectMapper();

    @DocStringType
    public JsonNode json(String docString) throws JsonProcessingException {
        return objectMapper.readValue(docString, JsonNode.class);
    }

    @Given("Books are defined by json")
    public void books_are_defined_by_json(JsonNode books) {
        // step implementation
    }
}    

For lambda defined step definitions, there are DataTableType, ParameterType and DocStringType functions:

package com.example;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

import io.cucumber.java8.En;

import java.util.Map;

public class LambdaStepDefinitions implements En {
    
    private static ObjectMapper objectMapper = new ObjectMapper();

    public LambdaStepDefinitions() {
        
        DataTableType((Map<String, String> entry) -> new Author(
            entry.get("firstName"),
            entry.get("lastName"),
            entry.get("famousBook")
        ));

        ParameterType("book", ".*", (String bookName) -> new Book(bookName));

        DocStringType("json", (String docString) -> 
            objectMapper.readValue(docString, JsonNode.class));
    }
}

Using the @DefaultParameterTransformer, @DefaultDataTableEntryTransformer and @DefaultDataTableCellTransformer annotations, it is also possible to plug in an ObjectMapper. The object mapper (Jackson in this example) will handle the conversion of anonymous parameter types and data table entries.

package com.example;

import com.fasterxml.jackson.databind.ObjectMapper;
import io.cucumber.java.DefaultDataTableCellTransformer;
import io.cucumber.java.DefaultDataTableEntryTransformer;
import io.cucumber.java.DefaultParameterTransformer;

import java.lang.reflect.Type;

public class StepDefinitions {

    private final ObjectMapper objectMapper = new ObjectMapper();

    @DefaultParameterTransformer
    @DefaultDataTableEntryTransformer
    @DefaultDataTableCellTransformer
    public Object transformer(Object fromValue, Type toValueType) {
        return objectMapper.convertValue(fromValue, objectMapper.constructType(toValueType));
    }
}

For lambda defined step definitions, there are DefaultParameterTransformer, DefaultDataTableCellTransformer and DefaultDataTableEntryTransformer methodfunctionblockfunction:

package com.example;

import io.cucumber.java8.En;

import com.fasterxml.jackson.databind.ObjectMapper;

import java.lang.reflect.Type;

public class LambdaStepDefinitions implements En {
    
    public LambdaStepDefinitions() {
        ObjectMapper objectMapper = new ObjectMapper();

        DefaultParameterTransformer((String fromValue, Type toValueType) ->
            objectMapper.convertValue(fromValue, objectMapper.constructType(toValueType)));

        DefaultDataTableCellTransformer((fromValue, toValueType) ->
            objectMapper.convertValue(fromValue, objectMapper.constructType(toValueType)));

        DefaultDataTableEntryTransformer((fromValue, toValueType) ->
            objectMapper.convertValue(fromValue, objectMapper.constructType(toValueType)));
    }
}    

If you are using a type that has not yet been defined, you will get an error similar to:

The parameter type "person" is not defined.

Cucumber profiles are not available on Cucumber-JVM. However, it is possible to set configuration options using Maven profiles.

For instance, we can configure separate profiles for scenarios which are to be run in separate environments like so:

    <profiles>
        <profile>
          <id>dev</id>
            <properties>
                <cucumber.options>--tags "@dev and not @ignore"</cucumber.options>
            </properties>
        </profile>
        <profile>
          <id>qa</id>
            <properties>
                <cucumber.options>--tags "@qa"</cucumber.options>
            </properties>
        </profile>
    </profiles>

    <build>
        <plugins>
            ...
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>3.0.0-M4</version>
                <configuration>
                    <systemPropertyVariables>
                       <cucumber.options>${cucumber.options}</cucumber.options>
                    </systemPropertyVariables>
                </configuration>
            </plugin>
        </plugins>
    </build>

To mimick similar behavior using Gradle, see the Gradle docs on Migrating Maven profiles and properties.

Cucumber profiles are not available on Cucumber-JVM. See above.

ERB (Embedded RuBy) is a Ruby specific tool.

Cucumber-JVM does not support configuration of Cucumber with an env file.