Class Wrapper

src/main/java/org/codehaus/groovy/runtime/wrappers/Wrapper.java:28–85

Base class for runtime wrappers that expose a value through GroovyObject while reporting a constrained type.

 * {@link GroovyObject} while reporting a constrained type.
 */
public abstract class Wrapper implements GroovyObject {
    /**
     * The constrained type the wrapped value should present to the runtime.
     */
    protected final Class constrainedType;

    /**
     * Creates a wrapper for values that should appear as the supplied type.
     *
     * @param constrainedType the type the wrapped value should report
     */
    public Wrapper(final Class constrainedType) {
        this.constrainedType = constrainedType;
    }

    /**
     * Returns the {@link MetaClass} used to service GroovyObject operations for
     * the wrapped value.
     *
     * @return the delegated meta class
     */
    @Override
    public MetaClass getMetaClass() {
        return getDelegatedMetaClass();
    }

    /**
     * Returns the constrained type associated with this wrapper.
     *
     * @return the type the wrapped value should be treated as
     */
    public Class getType() {
        return this.constrainedType;
    }

    /**
     * Returns the wrapped value.
     *
     * @return the underlying value represented by this wrapper
     */
    public abstract Object unwrap();

    /**
     * Returns the object used as the delegation target for meta-class-based
     * operations.
     *
     * @return the underlying wrapped object
     */
    protected abstract Object getWrapped();

    /**
     * Returns the meta class that should handle GroovyObject operations for the
     * wrapped value.
     *
     * @return the delegated meta class
     */
    protected abstract MetaClass getDelegatedMetaClass();
}