@Accessors

A more fluent API for getters and setters.

@Accessors was introduced as experimental feature in lombok v0.11.0.

The lombok.config option lombok.accessors.capitalization = [basic | beanspec] was added in lombok v1.18.24.

FUNCTIONAL CHANGE: @Accessors now 'cascades'; any options not set on a field-level @Accessors annotation will get inherited from an @Accessors annotation on the class (and any options not set on those, from the enclosing class). Finally, anything set in lombok.config will be used as default. (lombok v1.18.24)

NEW FEATURE: @Accessors(makeFinal = true) will create final getters, setters, and with-ers. There's also lombok.config key lombok.accessors.makeFinal for the same effect. (lombok v1.18.24)

Experimental

Experimental because:

We may want to roll these features into a more complete property support concept.
The makeFinal feature is recently released; awaiting community feedback.

Current status: neutral - Some changes are expected. These changes are intended to be backwards compatible, but should start in an experimental feature:

Open feature request: More control over naming accessors; for example to address creatively named boolean properties: Turn boolean wasRunning into boolean wasRunning() instead of boolean isWasRunning(), as well as more expansive prefix support. @Accessors will be involved if this feature request is addressed.
@Accessors currently does not 'cascade' from field @Accessors annotation to the class-level @Accessors annotation, but it does 'cascade' to lombok.config. Changing this is not difficult but backwards incompatible. It's not likely to break much existing code, but this needs to be decided on before the feature can move out of experimental status.

Overview

The @Accessors annotation is used to configure how lombok generates and looks for getters, setters, and with-ers.

By default, lombok follows the bean specification for getters and setters: The getter for a field named pepper is getPepper for example. However, some might like to break with the bean specification in order to end up with nicer looking APIs. @Accessors lets you do this.

Some programmers like to use a prefix for their fields, i.e. they write fPepper instead of pepper. We strongly discourage doing this, as you can't unit test the validity of your prefixes, and refactor scripts may turn fields into local variables or method names. Furthermore, your tools (such as your editor) can take care of rendering the identifier in a certain way if you want this information to be instantly visible. Nevertheless, you can list the prefixes that your project uses via @Accessors as well.

@Accessors has 4 options:

fluent – A boolean. If true, the getter for pepper is just pepper(), and the setter is pepper(T newValue). Furthermore, unless specified, chain defaults to true.
Default: false.
chain – A boolean. If true, generated setters return this instead of void.
Default: false, unless fluent=true, then Default: true.
makeFinal – A boolean. If true, generated getters, setters, and with-ers are marked as final.
Default: false.
prefix – A list of strings. If present, fields must be prefixed with any of these prefixes. Each field name is compared to each prefix in the list in turn, and if a match is found, the prefix is stripped out to create the base name for the field. It is legal to include an empty string in the list, which will always match. For characters which are letters, the character following the prefix must not be a lowercase letter, i.e. pepper is not a match even to prefix p, but pEpper would be (and would mean the base name of this field is epper).

The @Accessors annotation is legal on types and fields; getters/setters/with-ers will look at the annotation on the field first, on the type the field is in second (and you have types in types, each outer type is also checked), and finally for any properties not explicitly set, the appropriate lombok.config setting is used.

With Lombok


import lombok.experimental.Accessors;

import lombok.Getter;

import lombok.Setter;



@Accessors(fluent = true)

public class AccessorsExample {

  @Getter @Setter

  private int age = 10;

}



class PrefixExample {

  @Accessors(prefix = "f") @Getter

  private String fName = "Hello, World!";

}

Vanilla Java


public class AccessorsExample {

  private int age = 10;

  

  public int age() {

    return this.age;

  }

  

  public AccessorsExample age(final int age) {

    this.age = age;

    return this;

  }

}



class PrefixExample {

  private String fName = "Hello, World!";

  

  public String getName() {

    return this.fName;

  }

}

Supported configuration keys:

lombok.accessors.chain = [true | false] (default: false): If set to true, any field/class that either doesn't have an @Accessors annotation, or it does, but that annotation does not have an explicit value for the chain parameter, will act as if @Accessors(chain = true) is present.
lombok.accessors.fluent = [true | false] (default: false): If set to true, any field/class that either doesn't have an @Accessors annotation, or it does, but that annotation does not have an explicit value for the fluent parameter, will act as if @Accessors(fluent = true) is present.
lombok.accessors.makeFinal = [true | false] (default: false): If set to true, any field/class that either doesn't have an @Accessors annotation, or it does, but that annotation does not have an explicit value for the makeFinal parameter, will act as if @Accessors(makeFinal = true) is present.
lombok.accessors.prefix += a field prefix (default: empty list): This is a list property; entries can be added with the += operator. Inherited prefixes from parent config files can be removed with the -= operator. Any class that either doesn't have an @Accessors annotation, or it does, but that annotation does not have an explicit value for the prefix parameter, will act as if @Accessors(prefix = {prefixes listed in configuration}) is present.
lombok.accessors.capitalization = [basic | beanspec] (default: basic): Controls how tricky cases like uShaped (one lowercase letter followed by an upper/titlecase letter) are capitalized. basic capitalizes that to getUShaped, and beanspec capitalizes that to getuShaped instead.
Both strategies are commonly used in the java ecosystem, though beanspec is more common.
lombok.accessors.flagUsage = [warning | error] (default: not set): Lombok will flag any usage of @Accessors as a warning or error if configured.

Small print

The nearest @Accessors annotation is also used for the various methods in lombok that look for getters, such as @EqualsAndHashCode.

If a prefix list is provided and a field does not start with one of them, that field is skipped entirely by lombok, and a warning will be generated.