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Beans Package

The org.apache.juneau.commons.bean package provides Juneau's bean-modeling layer — the annotations and introspection engine that describe how Java beans are recognized, read, written, and mapped, independently of any particular marshalling format. The marshalling modules build on this layer through a small set of SPI seams so the bean model stays decoupled from serialization concerns.

Bean Modeling Annotations​

Annotations that control how classes and their properties are introspected.

BeanType​

Applied to a class to control bean introspection and modeling — property inclusion/order, read-only/write-only properties, a custom PropertyNamer, a stop class, and more.

@BeanType(properties="id,name,city", propertyNamer=PropertyNamerDLC.class)
public class Address {
    public String id, name, city;
}

BeanProp​

Applied to fields, getters/setters, or constructor parameters to control property modeling — most commonly to override the property name via its value()/name().

public class Person {
    @BeanProp("full-name")
    public String getName() { ... }
}

BeanCtor​

Maps constructor arguments to property names on beans with read-only properties.

public class Point {
    public final int x, y;

    @BeanCtor(properties="x,y")
    public Point(int x, int y) { this.x = x; this.y = y; }
}

BeanIgnore​

Excludes a class, field, method, or constructor from bean introspection.

public class Account {
    public String username;

    @BeanIgnore
    public String getPasswordHash() { ... }   // never treated as a bean property
}

Name​

Specifies the parameter name used for bean property mapping (e.g. on a constructor parameter).

public Point(@Name("x") int x, @Name("y") int y) { ... }

BeanConfig​

Specifies bean-modeling config properties (visibility rules, property-namer, not-bean packages/classes, etc.) on REST classes and methods.

Bean Introspection Runtime​

The runtime types that hold and expose bean metadata.

BeanMeta​

Encapsulates all access to the properties of a bean class (like a souped-up java.beans.BeanInfo). Obtained via the static factory.

BeanMeta<Address> bm = BeanMeta.of(Address.class);

BeanInfo​

SPI seam exposing the type-classification surface (is-bean, element/key/value types, instantiation) that the bean-runtime types need without coupling the bean-modeling layer to the marshalling layer.

BeanMap​

A Map-style wrapper around a Java bean, exposing its properties as map entries backed by BeanMeta.

BeanMap<Address> m = BeanMap.of(new Address());
m.put("city", "Portland");
Object city = m.get("city");

BeanMapEntry​

Represents a single entry in a BeanMap.

BeanPropertyMeta​

Contains metadata about a single bean property.

BeanPropertyValue​

Represents a simple bean property value together with the metadata associated with it.

BeanSession​

The minimum runtime surface the bean-modeling layer needs from a marshalling session.

BeanConfigContext​

Immutable runtime configuration for the bean-modeling layer, built via its nested Builder.

Property Naming​

Converts conventional bean property names into other conventions.

PropertyNamer​

Defines the API for converting a conventional bean property name to some other form.

public interface PropertyNamer {
    String getPropertyName(String name);
}

BasicPropertyNamer​

The default namer — returns property names unchanged.

PropertyNamerDLC​

Converts property names to dashed-lower-case format (fooBar → foo-bar).

PropertyNamerDUCS​

Converts property names to dashed-upper-case-start format.

PropertyNamerULC​

Converts property names to underscore-lower-case format (fooBar → foo_bar).

Property Validation​

Optional schema-driven validation of bean-property values.

PropertyValidator​

Validates a bean-property value against a schema, throwing SchemaValidationException on failure.

void validate(Object value) throws SchemaValidationException;

PropertyValidatorFactory​

Builds PropertyValidator instances from a JSON-Schema-shaped map of constraints.

PropertyValidators​

Discovery helper that locates a PropertyValidatorFactory via ServiceLoader.

Extension Points (SPI)​

Seams that let the marshalling layer plug into the bean model without the bean-modeling package depending on marshalling.

BeanInterceptor​

Intercepts bean property reads and writes, allowing values to be transformed during introspection. BeanInterceptor.Void is the non-existent (no-op) placeholder.

BeanFilter​

Exposes the per-class filter surface the bean-runtime types need, decoupled from the marshalling-side filter.

BeanMetaInitializer​

Exposes marshalling-aware BeanMeta construction hooks.

BeanPropertyPostProcessor​

Applies marshalling-side post-processing to a BeanPropertyMeta.Builder after its validation succeeds.

BeanRegistryLookup​

Exposes the dictionary-lookup surface the bean-runtime types need, decoupled from the marshalling-side bean registry.

BeanTypeResolver​

Exposes the type-resolution operations that the bean-property validation pass needs from the marshalling layer.

Delegate​

Marks an object that represents (wraps) another object.

BeanProxyInvocationHandler​

Provides an InvocationHandler for creating dynamic proxy instances of bean interfaces.

See Also​