dc-commons-yaml

DigitalCollections Commons YAML

Efficient toString() implementations

The main purpose of de.digitalcollections.commons.yaml is to provide easy to use toString()-implementations using YAML. This is particularily useful because one can use any String representation from a log file can be used to recreate the desired object in a unit test. Additionally, any toString()-implemetation via this library is idependent from the Object implemetation, so you don't have to change toString() if the object changes.

Example:

package de.digitalcollections.commons.yaml.examples;

import org.joda.time.DateTime;
import static de.digitalcollections.commons.yaml.StringRepresentations.stringRepresentationOf;

public class Book {

  private Person author;

  private String title;

  private DateTime published;

  private Book() {}

  // [...] Omitted other constructors and getters/setters.

  @Override
  public String toString() {
    return stringRepresentationOf(this);
  }

}

Using with some Data (for details see de.digitalcollections.commons.yaml.examples):

Person arkadiStrugatzki = new Person("Arkadi", "Strugatzki", DateTime.parse("1925-08-28"));
Book roadsidePicknic = new Book(arkadiStrugatzki, "Roadside Picknic", DateTime.parse("1971"));

System.out.println(roadsidePicknic.toString());

!!de.digitalcollections.commons.yaml.examples.Book {author: {bornAt: !!timestamp '1925-08-27T23:00:00Z', firstName: Arkadi, lastName: Strugatzki}, published: !!timestamp '1970-12-31T23:00:00Z', title: Roadside Picknic}

Some Benchmarks on serialization speed. Shown is mean execution time of one toString() call (see source code for details):

Running de.digitalcollections.commons.yaml.examples.BenchmarkTest
Book    93,6 µs   49,0 µs   34,4 µs
Person  22,4 µs   21,0 µs   28,6 µs