org.celeria.minecraft.backup.DeleteOldBackupsTask.java Source code

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Here is the source code for org.celeria.minecraft.backup.DeleteOldBackupsTask.java

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/*
 * Copyright 2011 Ian D. Bollinger
 *
 * 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.celeria.minecraft.backup;

import javax.annotation.concurrent.Immutable;
import com.google.inject.*;
import org.apache.commons.vfs2.*;
import org.celeria.minecraft.backup.BackUpWorldsTask.BackupFolder;
import org.joda.time.*;
import org.slf4j.cal10n.LocLogger;

@Immutable
class DeleteOldBackupsTask implements Runnable {
    private final LocLogger log;
    private final FileProvider<FileObject> backupFolderProvider;
    private final Duration durationToKeepBackups;
    private final Instant currentTime;

    @Inject
    DeleteOldBackupsTask(final LocLogger log, @BackupFolder final FileProvider<FileObject> backupFolderProvider,
            final Duration durationToKeepBackups, final Instant currentTime) {
        this.log = log;
        this.backupFolderProvider = backupFolderProvider;
        this.durationToKeepBackups = durationToKeepBackups;
        this.currentTime = currentTime;
    }

    @Override
    public void run() {
        try {
            deleteOldBackups();
        } catch (final FileSystemException e) {
            log.error(ErrorMessage.CANNOT_ACCESS_BACKUP, e);
        }
    }

    private void deleteOldBackups() throws FileSystemException {
        for (final FileObject backup : getBackupFolderContents()) {
            deleteBackupIfOld(backup);
        }
    }

    private FileObject[] getBackupFolderContents() throws FileSystemException {
        return backupFolderProvider.get().getChildren();
    }

    private void deleteBackupIfOld(final FileObject backup) throws FileSystemException {
        if (backupIsOld(backup)) {
            deleteBackup(backup);
        }
    }

    private boolean backupIsOld(final FileObject backup) throws FileSystemException {
        final long lastModifiedTime = backup.getContent().getLastModifiedTime();
        final Instant instant = new Instant(lastModifiedTime);
        return currentTime.plus(durationToKeepBackups).isAfter(instant);
    }

    private void deleteBackup(final FileObject backup) throws FileSystemException {
        // TODO: try to move this further up the application stack.
        backup.delete();
        log.info(LogMessage.DELETED_BACKUP, backup);
    }
}