hivesterix/hivesterix-serde/src/main/java/edu/uci/ics/hivesterix/serde/lazy/objectinspector/primitive/LazyPrimitiveObjectInspectorFactory.java

/*
 * Copyright 2009-2013 by The Regents of the University of California
 * 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 from
 * 
 *     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.
 */
/**
 * 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.
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package edu.uci.ics.hivesterix.serde.lazy.objectinspector.primitive;

import java.util.ArrayList;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector.PrimitiveCategory;

/**
 * LazyPrimitiveObjectInspectorFactory is the primary way to create new
 * ObjectInspector instances.
 * SerDe classes should call the static functions in this library to create an
 * ObjectInspector to return to the caller of SerDe2.getObjectInspector().
 * The reason of having caches here is that ObjectInspector is because
 * ObjectInspectors do not have an internal state - so ObjectInspectors with the
 * same construction parameters should result in exactly the same
 * ObjectInspector.
 */
public final class LazyPrimitiveObjectInspectorFactory {

    public static final LazyBooleanObjectInspector LAZY_BOOLEAN_OBJECT_INSPECTOR = new LazyBooleanObjectInspector();
    public static final LazyByteObjectInspector LAZY_BYTE_OBJECT_INSPECTOR = new LazyByteObjectInspector();
    public static final LazyShortObjectInspector LAZY_SHORT_OBJECT_INSPECTOR = new LazyShortObjectInspector();
    public static final LazyIntObjectInspector LAZY_INT_OBJECT_INSPECTOR = new LazyIntObjectInspector();
    public static final LazyLongObjectInspector LAZY_LONG_OBJECT_INSPECTOR = new LazyLongObjectInspector();
    public static final LazyFloatObjectInspector LAZY_FLOAT_OBJECT_INSPECTOR = new LazyFloatObjectInspector();
    public static final LazyDoubleObjectInspector LAZY_DOUBLE_OBJECT_INSPECTOR = new LazyDoubleObjectInspector();
    public static final LazyVoidObjectInspector LAZY_VOID_OBJECT_INSPECTOR = new LazyVoidObjectInspector();

    static ConcurrentHashMap<ArrayList<Object>, LazyStringObjectInspector> cachedLazyStringObjectInspector = new ConcurrentHashMap<ArrayList<Object>, LazyStringObjectInspector>();

    public static LazyStringObjectInspector getLazyStringObjectInspector(boolean escaped, byte escapeChar) {
        ArrayList<Object> signature = new ArrayList<Object>();
        signature.add(Boolean.valueOf(escaped));
        signature.add(Byte.valueOf(escapeChar));
        LazyStringObjectInspector result = cachedLazyStringObjectInspector.get(signature);
        if (result == null) {
            result = new LazyStringObjectInspector(escaped, escapeChar);
            cachedLazyStringObjectInspector.put(signature, result);
        }
        return result;
    }

    public static AbstractPrimitiveLazyObjectInspector<?> getLazyObjectInspector(PrimitiveCategory primitiveCategory,
            boolean escaped, byte escapeChar) {

        switch (primitiveCategory) {
            case BOOLEAN:
                return LAZY_BOOLEAN_OBJECT_INSPECTOR;
            case BYTE:
                return LAZY_BYTE_OBJECT_INSPECTOR;
            case SHORT:
                return LAZY_SHORT_OBJECT_INSPECTOR;
            case INT:
                return LAZY_INT_OBJECT_INSPECTOR;
            case LONG:
                return LAZY_LONG_OBJECT_INSPECTOR;
            case FLOAT:
                return LAZY_FLOAT_OBJECT_INSPECTOR;
            case DOUBLE:
                return LAZY_DOUBLE_OBJECT_INSPECTOR;
            case STRING:
                return getLazyStringObjectInspector(escaped, escapeChar);
            case VOID:
                return LAZY_VOID_OBJECT_INSPECTOR;
            default:
                throw new RuntimeException("Internal error: Cannot find ObjectInspector " + " for " + primitiveCategory);
        }
    }

    private LazyPrimitiveObjectInspectorFactory() {
        // prevent instantiation
    }

}