Java-Properties

Java Properties attempts to provide a similar experience to C# and Kotlin's properties by wrapping fields around Property<> and MutableProperty<> classes.

Installation

See the "releases" tag on the sidebar, download the JAR, and import it into your project!

Advantages

• Enforces the use of name.set(newName) and name.get() everywhere, even within the class. If different behaviour is required within and outside the class, a private Property can be used with a public Property that delegates to the private one with Property.ofProperty(otherProperty).
• Allows for easier modification when changing the way fields are accessed or set, and eliminating the need for boilerplate getName() and setName() setter and getter methods.

Usage

To define a Person class with a single property name that is mutable:

class Person {
  public final MutableProperty<String> name = MutableProperty.ofEmpty();
  
  Person(String name) {
    this.name.set(name);
  }
}

To change this so that the name is always uppercase, the code can simply be changed to add a custom setter:

class Person {
  public final MutableProperty<String> name = MutableProperty.withValue((String) null)
      .withSetter(String::toUpperCase)
      .build();
  
  Person(String name) {
    this.name.set(name);
  }
}

Alternatively, to have another property that relies on the value of name, say, uppercaseName, we can use ofProperty, which we can then add a custom getter to such that uppercaseName.get() is equivalent to name.get().toUpperCase():

class Person {
    public final MutableProperty<String> name = MutableProperty.ofEmpty();
    public final Property<String> uppercaseName = Property.withProperty(name)
            .withGetter(String::toUpperCase)
            .build();

    Person(String name) {
        this.name.set(name);
    }
}

Leaving all external code the same with myPerson.name.get() to get the value, myPerson.name.set(String) to set the value, and myPerson.uppercaseName.get() to get the uppercase value.

For compatibility with normal fields, delegateTo() can be used:

class Person {
    public String name;
    public final Property<String> uppercaseName = Property.delegateTo(() -> name.toUpperCase());

    Person(String name) {
        this.name = name;
    }
}