Accessor method
An accessor method or function provides access to an object's property or state by retrieving its value, assigning a value, or defining behavior for such access.
Web Components in Action
- How it is used
- Makes Web Components configurable through properties and lets property access trigger component behavior.
- How deep it goes
- Works through concrete getters, setters, and attribute reflection; stops short of explaining accessor internals.
- Examples
- Uses search options and reflected slider values and colors to demonstrate accessors.
- What you can do after
- Apply accessors to configure component searches or update a slider through its properties.
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100 C++ Mistakes and How to Avoid Them
An accessor is a class member function that provides access to an object's state without defining the object's state-changing operation.
- How it is used
- Uses accessors to expose necessary state while maintaining class invariants and reducing client dependence on representation.
- How deep it goes
- Explains trivial versus computing accessors, then stops short of prescribing universal getter-and-setter rules.
- Examples
- Demonstrates Circle area computation and Date formatting built on a minimal accessor set.
- What you can do after
- Diagnose unnecessary accessors, replace redundant state with computed results, and protect invariants during incremental maintenance.
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Kotlin in Action, 2E
A property accessor is a getter or setter that defines how a Kotlin property value is read or changed.
- How it is used
- Uses property accessors to encapsulate stored state, compute characteristics, and control mutation behind ordinary Kotlin property syntax.
- How deep it goes
- Explains default, computed, backing-field, visibility-controlled, interface, and reified accessors, while deferring delegated and late-initialized properties.
- Examples
- Demonstrates Rectangle.isSquare, interface nicknames, address-change logging, ageIn2050, LengthCounter, and a reified canonical extension property.
- What you can do after
- Build it from scratch, define getters and setters that compute values, update backing fields, and limit writes with private setters.
The Well-Grounded Rubyist, Fourth Edition
An attribute accessor method is a method that provides access to an object's attribute by reading or writing its value.
- How it is used
- Uses readers and writers to expose and change object state held in instance variables.
- How deep it goes
- Works through hand-written readers, assignment-style writers, validation, and automatic generation with `attr_*` methods.
- Examples
- Uses ticket prices, validated dollar amounts, normalized years, and inherited publication attributes.
- What you can do after
- Build it from scratch with reader and writer methods, or apply Ruby’s `attr_reader`, `attr_writer`, and `attr_accessor`.
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D3.js in Action, Third Edition
An accessor function is a callback that receives a bound datum and often its index to derive a value for a D3 operation.
- How it is used
- Uses callbacks to derive statistics, SVG attributes, styles, and generator coordinates from bound data.
- How deep it goes
- Explains callback parameters and return values through bar-chart code, then extends the pattern to area-generator boundaries.
- Examples
- Demonstrates technology counts, bar dimensions and positions, conditional colors, and minimum-to-maximum temperature areas.
- What you can do after
- Apply accessors via D3 methods to calculate values for each datum, index-based layout, conditional styling, and chart geometry.
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Clojure: The Essential Reference
Getter and setter methods are methods that respectively read and modify an object's exposed property values.
- How it is used
- Uses getters and setters to expose mutable type fields and JavaBean properties through methods.
- How deep it goes
- Shows complete getter and setter implementations with `deftype`, then discusses JavaBean conventions and reflective property conversion.
- Examples
- Demonstrates age getters and setters on a mutable type, struct-key lookup, and conversion of a Java point to a map.
- What you can do after
- Build it from scratch with `definterface` and `deftype` to expose a mutable field through getter and setter methods.
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Software Design for Python Programmers
A getter method is a method that reads an object's state through a public access interface without exposing its underlying representation.
- How it is used
- Encapsulates object state behind a public interface so callers remain independent of implementation details.
- How deep it goes
- Explains properties, validation, mutability hazards, lazy synchronization, and defensive copying through multiple worked examples.
- Examples
- Uses Item price properties, mutable Date Julian values, dangerous Date component setters, and Employee birthdate copies.
- What you can do after
- Build it from scratch with Python properties, validate mutations, preserve invariants, and prevent mutable state from leaking through getters.
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Java Persistence with Spring Data and Hibernate epub
A setter method is an accessor method that assigns a value to an object property.
- How it is used
- Supports Java domain properties that generic tools and persistence frameworks discover through JavaBeans conventions.
- How deep it goes
- Defines getter and setter naming, demonstrates accessor logic, and compares field access, but stops short of provider-specific configuration.
- Examples
- Uses User username accessors, computed and parsing name accessors, and Item validation performed through a setter-created state.
- What you can do after
- Apply JavaBeans naming and choose between accessor and field access when designing persistence-capable classes.
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Julia as a Second Language
A setter method is a method that assigns or updates a property of an object or structured value.
- How it is used
- Uses small functions to read structured values and setters to update them while protecting invariants.
- How deep it goes
- Explains ordinary accessor functions, indexing, higher-order use, validation, assignment, and DomainError handling.
- Examples
- Uses pizza sales records, map(name, sales), and a propellant setter for a rocket tank.
- What you can do after
- Apply it via Julia functions to read fields and reject invalid state changes with DomainError.
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Essential TypeScript 5, Third Edition
An accessor is a class function that controls reading or writing a property value through getter or setter syntax.
- How it is used
- Controls property access while inserting validation, conversion, or derived-value logic behind familiar property syntax.
- How deep it goes
- Explains getters, setters, backing fields, computed values, and read-only accessors through TypeScript examples.
- Examples
- Uses hat pricing, boots tax calculation, and an Employee location translated from cities.
- What you can do after
- Build it from scratch using TypeScript classes with private backing fields and property-style getter and setter access.
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Pro Angular 16
A getter is a class or object member that computes and returns a value when accessed as a property.
- How it is used
- Exposes model-derived values to Angular templates through property-style access.
- How deep it goes
- Explains getter syntax, template evaluation, performance costs, and a signal-based alternative, but not language-level accessor internals.
- Examples
- Uses product count, total price, message selection, template interpolation, and an intentionally expensive counting loop.
- What you can do after
- Evaluate when to expose derived template data with getters and when to replace repeated work with computed signals.
Python How-To
- How it is used
- Uses property setters to check values assigned to class properties while retaining attribute-style assignment.
- How deep it goes
- Explains the setter decorator and value checking, then cautions against routine getter-and-setter wrappers.
- Examples
- Checks Task status against four allowed values and poses an urgency setter challenge for integers from 1 to 5.
- What you can do after
- Apply it by defining a property setter that checks assigned values before updating the internal attribute.
Secrets of the JavaScript Ninja, Second Edition
A method used to retrieve or update a property or encapsulated state.
- How it is used
- Controls access to object properties or exposes closure-held state without direct access to its variable.
- How deep it goes
- Explains property getter and setter behavior and demonstrates closure-based state access through a constructor example.
- Examples
- Uses computed properties, validation and logging, and a Ninja constructor that exposes a private feints counter.
- What you can do after
- Apply getters and setters to expose calculated values, validate or log updates, and provide controlled access to closure-held state.
Read how Secrets of the JavaScript Ninja, Second Edition explains accessor method →
Related concepts
- stateuses · State is information or a configuration describing the condition of a system, entity, or computation at a particular time and potentially influencing subsequent behavior or decisions.
- immutable instance variablecontrasts with · An immutable instance variable is a data member whose value cannot be changed after its initialization.
- attributeuses · An attribute is a named property, value, or piece of information associated with an entity, object, or program element.
- methodkind of · A method is a callable operation associated with an object or type and invoked through that association.
- private memberuses · A private member is a program element whose direct access is restricted to its defining class, module, file, or other language-defined scope.
- encapsulationuses · Encapsulation is a software design principle that contains state and implementation details behind a controlled interface, limiting direct access from outside.
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