hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ErasureCodingPolicy.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.hadoop.hdfs.protocol;

import org.apache.hadoop.io.erasurecode.ECSchema;

import java.util.Map;

/**
 * A policy about how to write/read/code an erasure coding file.
 */
public final class ErasureCodingPolicy {

  private final String name;
  private final ECSchema schema;
  private final int cellSize;

  public ErasureCodingPolicy(String name, ECSchema schema, int cellSize){
    this.name = name;
    this.schema = schema;
    this.cellSize = cellSize;
  }

  public String getName() {
    return name;
  }

  public ECSchema getSchema() {
    return schema;
  }

  public int getCellSize() {
    return cellSize;
  }

  public int getNumDataUnits() {
    return schema.getNumDataUnits();
  }

  public int getNumParityUnits() {
    return schema.getNumParityUnits();
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    ErasureCodingPolicy that = (ErasureCodingPolicy) o;

    if (that.getName().equals(name) && that.getCellSize() == cellSize
        && that.getSchema().equals(schema)) {
      return true;
    }
    return false;
  }

  @Override
  public int hashCode() {
    int result = name.hashCode();
    result = 31 * result + schema.hashCode();
    result = 31 * result + cellSize;
    return result;
  }

  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder("ErasureCodingPolicy=[");
    sb.append("Name=" + name + ", ");
    sb.append("Schema=[" + schema.toString() + "], ");
    sb.append("CellSize=" + cellSize + " ");
    sb.append("]");
    return sb.toString();
  }
}