eagle-core/eagle-query/eagle-entity-base/src/main/java/org/apache/eagle/log/entity/meta/Partition.java

/*
 * 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.eagle.log.entity.meta;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Partition annotation will impact the rowkey generation for Eagle entities. Once an entity class 
 * has defined the partition fields for an Eagle entity, the hash codes of the defined partition 
 * fields will be placed just after prefix field, and before timestamp field.
 * 
 *
 */
@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface Partition
{
    /**
     * Order in which annotated tags are to be regarded as data partitions.
     */
    public String[] value() default { };

}