com.ibm.stocator.fs.common.ObjectStoreGlobFilter.java Source code

Introduction

Here is the source code for com.ibm.stocator.fs.common.ObjectStoreGlobFilter.java

Source

/**
 * (C) Copyright IBM Corp. 2015, 2016
 *
 * 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 com.ibm.stocator.fs.common;

import java.util.regex.PatternSyntaxException;
import java.io.IOException;

import org.apache.hadoop.fs.GlobPattern;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathFilter;

/**
 * A filter for POSIX glob pattern with brace expansions.
 */
public class ObjectStoreGlobFilter implements PathFilter {
    private static final PathFilter DEFAULT_FILTER = new PathFilter() {
        @Override
        public boolean accept(Path file) {
            return true;
        }
    };

    private PathFilter userFilter = DEFAULT_FILTER;
    private GlobPattern pattern;

    /**
     * Creates a glob filter with the specified file pattern.
     *
     * @param filePattern the file pattern
     * @throws IOException thrown if the file pattern is incorrect
     */
    public ObjectStoreGlobFilter(String filePattern) throws IOException {
        init(filePattern, DEFAULT_FILTER);
    }

    /**
     * Creates a glob filter with the specified file pattern and an user filter.
     *
     * @param filePattern the file pattern
     * @param filter user filter in addition to the glob pattern
     * @throws IOException thrown if the file pattern is incorrect
     */
    public ObjectStoreGlobFilter(String filePattern, PathFilter filter) throws IOException {
        init(filePattern, filter);
    }

    void init(String filePattern, PathFilter filter) throws IOException {
        try {
            userFilter = filter;
            pattern = new GlobPattern(filePattern);
        } catch (PatternSyntaxException e) {
            throw new IOException("Illegal file pattern: " + e.getMessage(), e);
        }
    }

    boolean hasPattern() {
        return pattern.hasWildcard();
    }

    @Override
    public boolean accept(Path path) {
        return pattern.matches(path.getName()) && userFilter.accept(path);
    }
}