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Commons IO example source code file (SizeFileFilter.java)

This example Commons IO source code file (SizeFileFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Commons IO tags/keywords

abstractfilefilter, illegalargumentexception, io, override, override, serializable, sizefilefilter, sizefilefilter, string, string, the, the

The Commons IO SizeFileFilter.java source code

/*
 * 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.io.filefilter;

import java.io.File;
import java.io.Serializable;

/**
 * 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:
 *
 * <pre>
 * File dir = new File(".");
 * String[] files = dir.list( new SizeFileFilter(1024 * 1024) );
 * for ( int i = 0; i < files.length; i++ ) {
 *     System.out.println(files[i]);
 * }
 * </pre>
 *
 * @author Rahul Akolkar
 * @version $Id: SizeFileFilter.java 1005099 2010-10-06 16:13:01Z niallp $
 * @since Commons IO 1.2
 * @see FileFilterUtils#sizeFileFilter(long)
 * @see FileFilterUtils#sizeFileFilter(long, boolean)
 * @see FileFilterUtils#sizeRangeFileFilter(long, long)
 */
public class SizeFileFilter extends AbstractFileFilter implements Serializable {

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

    /**
     * Constructs a new size file filter for files equal to or 
     * larger than a certain size.
     *
     * @param size  the threshold size of the files
     * @throws IllegalArgumentException if the size is negative
     */
    public SizeFileFilter(long size) {
        this(size, true);
    }

    /**
     * Constructs a new size file filter for files based on a certain size
     * threshold.
     *
     * @param size  the threshold size of the files
     * @param acceptLarger  if true, files equal to or larger are accepted,
     * otherwise smaller ones (but not equal to)
     * @throws IllegalArgumentException if the size is negative
     */
    public SizeFileFilter(long size, 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.
     * <p>
     * If size equals threshold and smaller files are required,
     * file <b>IS NOT selected.
     * If size equals threshold and larger files are required,
     * file <b>IS selected.
     *
     * @param file  the File to check
     * @return true if the filename matches
     */
    @Override
    public boolean accept(File file) {
        boolean smaller = file.length() < size;
        return acceptLarger ? !smaller : smaller;
    }

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

}

Other Commons IO examples (source code examples)

Here is a short list of links related to this Commons IO SizeFileFilter.java source code file:



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