org.apache.drill.exec.ref.rse.ClasspathRSE.java Source code

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Here is the source code for org.apache.drill.exec.ref.rse.ClasspathRSE.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
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package org.apache.drill.exec.ref.rse;

import java.io.IOException;
import java.net.URL;
import java.util.Collection;
import java.util.Collections;

import org.apache.drill.common.config.DrillConfig;
import org.apache.drill.common.expression.SchemaPath;
import org.apache.drill.common.logical.StorageEngineConfigBase;
import org.apache.drill.common.logical.data.Scan;
import org.apache.drill.exec.ref.exceptions.SetupException;
import org.apache.drill.exec.ref.rops.DataWriter.ConverterType;
import org.apache.drill.exec.ref.rops.ROP;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonTypeName;

public class ClasspathRSE extends RSEBase {
    static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(ClasspathRSE.class);

    private DrillConfig dConfig;
    private SchemaPath rootPath;

    public ClasspathRSE(ClasspathRSEConfig engineConfig, DrillConfig dConfig) throws SetupException {
        this.dConfig = dConfig;
    }

    @JsonTypeName("classpath")
    public static class ClasspathRSEConfig extends StorageEngineConfigBase {
        @JsonCreator
        public ClasspathRSEConfig(@JsonProperty("name") String name) {
            super(name);
        }
    }

    public static class ClasspathInputConfig implements ReadEntry {
        public String path;
        public ConverterType type;
        @JsonIgnore
        public SchemaPath rootPath;
    }

    public boolean supportsRead() {
        return true;
    }

    @Override
    public Collection<ReadEntry> getReadEntries(Scan scan) throws IOException {
        ClasspathInputConfig c = scan.getSelection().getWith(ClasspathInputConfig.class);
        c.rootPath = scan.getOutputReference();
        return Collections.singleton((ReadEntry) c);
    }

    @Override
    public RecordReader getReader(ReadEntry readEntry, ROP parentROP) throws IOException {
        ClasspathInputConfig e = getReadEntry(ClasspathInputConfig.class, readEntry);
        URL u = RecordReader.class.getResource(e.path);
        if (u == null) {
            throw new IOException(String.format("Failure finding classpath resource %s.", e.path));
        }
        switch (e.type) {
        case JSON:
            return new JSONRecordReader(e.rootPath, dConfig, u.openStream(), parentROP);
        default:
            throw new UnsupportedOperationException();
        }
    }

}