/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.commons.vfs2.filter;

import java.io.Serializable;

import org.apache.commons.vfs2.FileContent;
import org.apache.commons.vfs2.FileFilter;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSelectInfo;
import org.apache.commons.vfs2.FileSystemException;

Filters files based on size, can filter either smaller files or files equal
to or larger than a given threshold.

For example, to print all files and directories in the current directory
whose size is greater than 1 MB:

FileSystemManager fsManager = VFS.getManager();
FileObject dir = fsManager.toFileObject(new File("."));
SizeFileFilter filter = new SizeFileFilter(1024 * 1024);
FileObject[] files = dir.findFiles(new FileFilterSelector(filter));
for (int i = 0; i < files.length; i++) {
    System.out.println(files[i]);
}

Author:
This code was originally ported from Apache Commons IO File Filter
See Also:
http://commons.apache.org/proper/commons-io/
Since:
2.4/**
 * Filters files based on size, can filter either smaller files or files equal
 * to or larger than a given threshold.
 * <p>
 * For example, to print all files and directories in the current directory
 * whose size is greater than 1 MB:
 * </p>
 *
 * <pre>
 * FileSystemManager fsManager = VFS.getManager();
 * FileObject dir = fsManager.toFileObject(new File(&quot;.&quot;));
 * SizeFileFilter filter = new SizeFileFilter(1024 * 1024);
 * FileObject[] files = dir.findFiles(new FileFilterSelector(filter));
 * for (int i = 0; i &lt; files.length; i++) {
 *     System.out.println(files[i]);
 * }
 * </pre>
 *
 * @author This code was originally ported from Apache Commons IO File Filter
 * @see "http://commons.apache.org/proper/commons-io/"
 * @since 2.4
 */
public class SizeFileFilter implements FileFilter, Serializable {

    private static final long serialVersionUID = 1L;

    
Whether the files accepted will be larger or smaller. /** Whether the files accepted will be larger or smaller. */
    private final boolean acceptLarger;

    
The size threshold. /** The size threshold. */
    private final long size;

    
Constructs a new size file filter for files equal to or larger than a certain
size.
Params:
size – the threshold size of the files - Must be non-negative./**
     * Constructs a new size file filter for files equal to or larger than a certain
     * size.
     *
     * @param size the threshold size of the files - Must be non-negative.
     */
    public SizeFileFilter(final long size) {
        this(size, true);
    }

    
Constructs a new size file filter for files based on a certain size
threshold.
Params:
size –         the threshold size of the files - Must be non-negative.
acceptLarger – if true, files equal to or larger are accepted, otherwise
                    smaller ones (but not equal to)/**
     * Constructs a new size file filter for files based on a certain size
     * threshold.
     *
     * @param size         the threshold size of the files - Must be non-negative.
     * @param acceptLarger if true, files equal to or larger are accepted, otherwise
     *                     smaller ones (but not equal to)
     */
    public SizeFileFilter(final long size, final boolean acceptLarger) {
        if (size < 0) {
            throw new IllegalArgumentException("The size must be non-negative");
        }
        this.size = size;
        this.acceptLarger = acceptLarger;
    }

    
Checks to see if the size of the file is favorable.

If size equals threshold and smaller files are required, file IS NOT
selected. If size equals threshold and larger files are required, file
IS selected.


Non-existing files return always false (will never be accepted).

Params:
fileInfo – the File to check
Throws:
FileSystemException – Thrown for file system errors.
Returns:
true if the file name matches/**
     * Checks to see if the size of the file is favorable.
     * <p>
     * If size equals threshold and smaller files are required, file <b>IS NOT</b>
     * selected. If size equals threshold and larger files are required, file
     * <b>IS</b> selected.
     * </p>
     * <p>
     * Non-existing files return always false (will never be accepted).
     * </p>
     *
     * @param fileInfo the File to check
     *
     * @return true if the file name matches
     * @throws FileSystemException Thrown for file system errors.
     */
    @Override
    public boolean accept(final FileSelectInfo fileInfo) throws FileSystemException {
        try (final FileObject file = fileInfo.getFile()) {
            if (!file.exists()) {
                return false;
            }
            try (final FileContent content = file.getContent();) {
                final long length = content.getSize();
                final boolean smaller = length < size;
                return acceptLarger ? !smaller : smaller;
            }
        }
    }

    
Provide a String representation of this file filter.
Returns:
a String representation/**
     * Provide a String representation of this file filter.
     *
     * @return a String representation
     */
    @Override
    public String toString() {
        final String condition = acceptLarger ? ">=" : "<";
        return super.toString() + "(" + condition + size + ")";
    }

}