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A bundle project producing JAX-RS RI bundles. The primary artifact is an "all-in-one" OSGi-fied JAX-RS RI bundle (jaxrs-ri.jar). Attached to that are two compressed JAX-RS RI archives. The first archive (jaxrs-ri.zip) consists of binary RI bits and contains the API jar (under "api" directory), RI libraries (under "lib" directory) as well as all external RI dependencies (under "ext" directory). The secondary archive (jaxrs-ri-src.zip) contains buildable JAX-RS RI source bundle and contains the API jar (under "api" directory), RI sources (under "src" directory) as well as all external RI dependencies (under "ext" directory). The second archive also contains "build.xml" ANT script that builds the RI sources. To build the JAX-RS RI simply unzip the archive, cd to the created jaxrs-ri directory and invoke "ant" from the command line.

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/*
 * Copyright (C) 2010 The Guava Authors
 *
 * 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.glassfish.jersey.internal.guava;

import java.util.NoSuchElementException;

/**
 * This class provides a skeletal implementation of the {@code Iterator}
 * interface for sequences whose next element can always be derived from the
 * previous element. Null elements are not supported, nor is the
 * {@link #remove()} method.
 * 
 * 
Example: 
   {@code
 * 
 *   Iterator powersOfTwo =
 *       new AbstractSequentialIterator(1) {
 *         protected Integer computeNext(Integer previous) {
 *           return (previous == 1 << 30) ? null : previous * 2;
 *         }
 *       };}
 *
 * @author Chris Povirk
 * @since 12.0 (in Guava as {@code AbstractLinkedIterator} since 8.0)
 */
abstract class AbstractSequentialIterator
        extends UnmodifiableIterator {
    private T nextOrNull;

    /**
     * Creates a new iterator with the given first element, or, if {@code
     * firstOrNull} is null, creates a new empty iterator.
     */
    AbstractSequentialIterator(T firstOrNull) {
        this.nextOrNull = firstOrNull;
    }

    /**
     * Returns the element that follows {@code previous}, or returns {@code null}
     * if no elements remain. This method is invoked during each call to
     * {@link #next()} in order to compute the result of a future call to
     * {@code next()}.
     */
    protected abstract T computeNext(T previous);

    @Override
    public final boolean hasNext() {
        return nextOrNull != null;
    }

    @Override
    public final T next() {
        if (!hasNext()) {
            throw new NoSuchElementException();
        }
        try {
            return nextOrNull;
        } finally {
            nextOrNull = computeNext(nextOrNull);
        }
    }
}