tapestry/tapestry-framework/src/java/org/apache/tapestry/resolver/ComponentSpecificationResolver.java

// Copyright 2004, 2005 The Apache Software Foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package org.apache.tapestry.resolver;

import org.apache.hivemind.ApplicationRuntimeException;
import org.apache.hivemind.Location;
import org.apache.tapestry.INamespace;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.spec.IComponentSpecification;

/**
 * Service interface for locating component specifications.
 * 
 * @author Howard Lewis Ship
 * @since 4.0
 */
public interface ComponentSpecificationResolver
{
    /**
     * Passed the namespace of a container (to resolve the type in) and the type to resolve,
     * performs the processing. A "bare type" (without a library prefix) may be in the
     * containerNamespace, or the framework namespace (a search occurs in that order).
     * 
     * @param cycle
     *            current request cycle
     * @param containerNamespace
     *            namespace that may contain a library referenced in the type
     * @param type
     *            the component specification to find, either a simple name, or prefixed with a
     *            library id (defined for the container namespace)
     * @see #getNamespace()
     * @see #getSpecification()
     */
    void resolve(IRequestCycle cycle, INamespace containerNamespace, String type,
            Location location);

    /**
     * Like
     * {@link #resolve(org.apache.tapestry.IRequestCycle, org.apache.tapestry.INamespace, java.lang.String, Location)},
     * but used when the type has already been parsed into a library id and a simple type.
     * 
     * @param cycle
     *            current request cycle
     * @param containerNamespace
     *            namespace that may contain a library referenced in the type
     * @param libraryId
     *            the library id within the container namespace, or null
     * @param type
     *            the component specification to find as a simple name (without a library prefix)
     * @param location
     *            of reference to be resolved
     * @throws ApplicationRuntimeException
     *             if the type cannot be resolved
     */
    void resolve(IRequestCycle cycle, INamespace containerNamespace, String libraryId,
            String type, Location location);

    /**
     * The specification resolved by the resolve() method.
     */
    IComponentSpecification getSpecification();

    /**
     * The namespace containing the resolved component.
     */
    INamespace getNamespace();

    /**
     * Returns the unqualified type of the component (i.e., with any namespace prefix stripped off).
     */
    String getType();
}