org.neo4j.adversaries.pagecache.AdversarialPageCache.java Source code

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Here is the source code for org.neo4j.adversaries.pagecache.AdversarialPageCache.java

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/*
 * Copyright (c) 2002-2016 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.adversaries.pagecache;

import org.apache.commons.lang3.ArrayUtils;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.nio.file.OpenOption;
import java.nio.file.StandardOpenOption;
import java.util.Objects;

import org.neo4j.adversaries.Adversary;
import org.neo4j.io.pagecache.IOLimiter;
import org.neo4j.io.pagecache.PageCache;
import org.neo4j.io.pagecache.PagedFile;

/**
 * A {@linkplain PageCache page cache} that wraps another page cache and an {@linkplain Adversary adversary} to provide
 * a misbehaving page cache implementation for testing.
 * <p>
 * Depending on the adversary each operation can throw either {@link RuntimeException} like {@link SecurityException}
 * or {@link IOException} like {@link FileNotFoundException}.
 */
@SuppressWarnings("unchecked")
public class AdversarialPageCache implements PageCache {
    private final PageCache delegate;
    private final Adversary adversary;

    public AdversarialPageCache(PageCache delegate, Adversary adversary) {
        this.delegate = Objects.requireNonNull(delegate);
        this.adversary = Objects.requireNonNull(adversary);
    }

    @Override
    public PagedFile map(File file, int pageSize, OpenOption... openOptions) throws IOException {
        if (ArrayUtils.contains(openOptions, StandardOpenOption.CREATE)) {
            adversary.injectFailure(IOException.class, SecurityException.class);
        } else {
            adversary.injectFailure(FileNotFoundException.class, IOException.class, SecurityException.class);
        }
        PagedFile pagedFile = delegate.map(file, pageSize, openOptions);
        return new AdversarialPagedFile(pagedFile, adversary);
    }

    @Override
    public void flushAndForce() throws IOException {
        adversary.injectFailure(FileNotFoundException.class, IOException.class, SecurityException.class);
        delegate.flushAndForce();
    }

    @Override
    public void flushAndForce(IOLimiter limiter) throws IOException {
        adversary.injectFailure(FileNotFoundException.class, IOException.class, SecurityException.class);
        delegate.flushAndForce(limiter);
    }

    @Override
    public void close() throws IOException {
        adversary.injectFailure(FileNotFoundException.class, IOException.class, SecurityException.class);
        delegate.close();
    }

    @Override
    public int pageSize() {
        return delegate.pageSize();
    }

    @Override
    public int maxCachedPages() {
        return delegate.maxCachedPages();
    }
}