com.fasterxml.jackson.databind.exc.MismatchedInputException: No content to map due to end-of-input at [Source: (String)""; line: 1, column: 0]

Question

Why am I receiving the exception below?

package test2;

import java.util.HashMap;
import java.util.Map;

import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;

public class test2 {
    public static void main(String[] args) {
        System.out.print("Started!");

        String jsonMap = "";
        Map<String, String> map = new HashMap<String, String>();
        try {
            TypeReference<HashMap<String, String>> typeRef = new TypeReference<HashMap<String, String>>() {
            };
            map.putAll(fromJSONString(jsonMap, typeRef));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static <T extends Object> T fromJSONString(String str, TypeReference<T> typeRef) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        mapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
        mapper.setSerializationInclusion(Include.NON_DEFAULT);
        mapper.setSerializationInclusion(Include.NON_NULL);
        mapper.setSerializationInclusion(Include.NON_EMPTY);
        mapper.configure(DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, true);
        return mapper.readValue(str, typeRef);
    }
}

POM:

<dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.16.1</version>
        </dependency>

        <dependency>
            <groupId>commons-collections</groupId>
            <artifactId>commons-collections</artifactId>
            <version>3.2</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.dataformat</groupId>
            <artifactId>jackson-dataformat-xml</artifactId>
            <version>2.16.1</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.16.1</version>
        </dependency>
    </dependencies>

Exception:

com.fasterxml.jackson.databind.exc.MismatchedInputException: No content to map due to end-of-input at [Source: (String)""; line: 1, column: 0] at com.fasterxml.jackson.databind.exc.MismatchedInputException.from(MismatchedInputException.java:59) at com.fasterxml.jackson.databind.ObjectMapper._initForReading(ObjectMapper.java:4765) at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4667) at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3629) at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3612) at test2.test2.fromJSONString(test2.java:34) at test2.test2.main(test2.java:21)

I added this row, but it hadn't impacted the behavior:

mapper.configure(DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, true);