org.springframework.data.hadoop.store.strategy.naming.CodecFileNamingStrategy.java Source code

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Here is the source code for org.springframework.data.hadoop.store.strategy.naming.CodecFileNamingStrategy.java

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/*
 * Copyright 2013 the original author or authors.
 *
 * 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.springframework.data.hadoop.store.strategy.naming;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.Path;
import org.springframework.data.hadoop.store.codec.CodecInfo;
import org.springframework.util.StringUtils;

/**
 * A {@code FileNamingStrategy} which adds suffix based on known codec.
 *
 * @author Janne Valkealahti
 *
 */
public class CodecFileNamingStrategy extends AbstractFileNamingStrategy {

    private final static Log log = LogFactory.getLog(CodecFileNamingStrategy.class);

    /**
     * Instantiates a new codec file naming strategy.
     */
    public CodecFileNamingStrategy() {
    }

    @Override
    public int getOrder() {
        return LOWEST_PRECEDENCE - 1;
    }

    @Override
    public Path resolve(Path path) {
        CodecInfo c = getCodecInfo();
        String suffix = c != null ? "." + c.getDefaultSuffix() : "";
        if (path != null) {
            return path.suffix(suffix);
        } else if (StringUtils.hasText(suffix)) {
            return new Path(suffix);
        } else {
            return path;
        }
    }

    @Override
    public void reset() {
    }

    @Override
    public Path init(Path path) {
        path = super.init(path);
        log.debug("Initialising from path=" + path);

        CodecInfo c = getCodecInfo();
        String suffix = c != null ? "." + c.getDefaultSuffix() : "";

        if (path != null && StringUtils.hasText(suffix)) {
            if (path.getName().startsWith(suffix)) {
                String name = path.getName().substring(suffix.length());
                if (StringUtils.hasText(name)) {
                    path = new Path(path.getParent(), name);
                    log.debug("Removed handled prefix, path is now " + path);
                } else {
                    path = null;
                    log.debug("Removed last handled name part, returning null");
                }
            }
        }
        return path;
    }

}