SearchRow.java

/*
 * Copyright 2014-2015 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 com.wplatform.ddal.result;

import com.wplatform.ddal.value.Value;

/**
 * The interface for rows stored in a table, and for partial rows stored in the
 * index.
 */
public interface SearchRow {

    /**
     * An empty array of SearchRow objects.
     */
    SearchRow[] EMPTY_ARRAY = {};

    /**
     * Get the column count.
     *
     * @return the column count
     */
    int getColumnCount();

    /**
     * Get the value for the column
     *
     * @param index the column number (starting with 0)
     * @return the value
     */
    Value getValue(int index);

    /**
     * Set the value for given column
     *
     * @param index the column number (starting with 0)
     * @param v     the new value
     */
    void setValue(int index, Value v);

    /**
     * Set the position and version to match another row.
     *
     * @param old the other row.
     */
    void setKeyAndVersion(SearchRow old);

    /**
     * Get the version of the row.
     *
     * @return the version
     */
    int getVersion();

    /**
     * Get the unique key of the row.
     *
     * @return the key
     */
    long getKey();

    /**
     * Set the unique key of the row.
     *
     * @param key the key
     */
    void setKey(long key);

    /**
     * Get the estimated memory used for this row, in bytes.
     *
     * @return the memory
     */
    int getMemory();

}