org.apache.lens.lib.query.WrappedFileFormatter.java Source code

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Here is the source code for org.apache.lens.lib.query.WrappedFileFormatter.java

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/**
 * 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.lens.lib.query;

import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;

import org.apache.lens.server.api.driver.LensResultSetMetadata;
import org.apache.lens.server.api.query.QueryContext;

import org.apache.commons.lang.StringUtils;
import org.apache.hadoop.fs.Path;

/**
 * Wraps the formatter {@link FileFormatter}, which can have implementations like {@link HadoopFileFormatter} or
 * {@link ZipFileFormatter}.
 */
public abstract class WrappedFileFormatter extends AbstractOutputFormatter {

    /**
     * The formatter.
     */
    private AbstractFileFormatter formatter;

    /*
     * (non-Javadoc)
     *
     * @see org.apache.lens.lib.query.AbstractOutputFormatter#init(org.apache.lens.server.api.query.QueryContext,
     * org.apache.lens.server.api.driver.LensResultSetMetadata)
     */
    public void init(QueryContext ctx, LensResultSetMetadata metadata) throws IOException {
        super.init(ctx, metadata);
        if (ctx.splitResultIntoMultipleFiles()) {
            formatter = new ZipFileFormatter();
        } else {
            formatter = new HadoopFileFormatter();
        }
        formatter.init(ctx, metadata);
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.lens.server.api.query.QueryOutputFormatter#writeHeader()
     */
    @Override
    public void writeHeader() throws IOException {
        String header = ctx.getResultHeader();
        if (!StringUtils.isBlank(header)) {
            formatter.writeHeader(header);
        } else {
            formatter.writeHeader(getHeaderFromSerde());
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.lens.server.api.query.QueryOutputFormatter#writeFooter()
     */
    @Override
    public void writeFooter() throws IOException {
        String footer = ctx.getResultFooter();
        if (!StringUtils.isBlank(footer)) {
            formatter.writeFooter(footer);
        } else {
            formatter.writeFooter("Total rows:" + getNumRows());
        }
    }

    /**
     * Write row.
     *
     * @param row the row
     * @throws IOException Signals that an I/O exception has occurred.
     */
    protected void writeRow(String row) throws IOException {
        formatter.writeRow(row);
    }

    @Override
    public Integer getNumRows() {
        return formatter.getNumRows();
    }

    @Override
    public Long getFileSize() {
        return formatter.getFileSize();
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.lens.server.api.query.QueryOutputFormatter#commit()
     */
    @Override
    public void commit() throws IOException {
        formatter.commit();
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.lens.server.api.query.QueryOutputFormatter#close()
     */
    @Override
    public void close() throws IOException {
        if (formatter != null) {
            formatter.close();
        }
    }

    @Override
    public String getFinalOutputPath() {
        return formatter.getFinalOutputPath();
    }

    public Path getTmpPath() {
        return formatter.getTmpPath();
    }

    public String getEncoding() {
        return formatter.getEncoding();
    }

    @Override
    public void writeExternal(ObjectOutput out) throws IOException {
        out.writeObject(formatter);
    }

    @Override
    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
        formatter = (AbstractFileFormatter) in.readObject();
        metadata = formatter.getMetadata();
    }
}