/**
 * 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 org.apache.hadoop.test.GenericTestUtils;
import org.junit.Test;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;
import static org.junit.Assert.fail;

/**
 * Test ErasureCodingPolicy.
 */
public class TestErasureCodingPolicy {

  private static final ECSchema SCHEMA_1 = new ECSchema("one", 1, 2, null);
  private static final ECSchema SCHEMA_2 = new ECSchema("two", 1, 2, null);

  @Test
  public void testInvalid() {
    try {
      new ErasureCodingPolicy(null, SCHEMA_1, 123, (byte) -1);
      fail("Instantiated invalid ErasureCodingPolicy");
    } catch (NullPointerException e) {
    }
    try {
      new ErasureCodingPolicy("policy", null, 123, (byte) -1);
      fail("Instantiated invalid ErasureCodingPolicy");
    } catch (NullPointerException e) {
    }
    try {
      new ErasureCodingPolicy("policy", SCHEMA_1, -1, (byte) -1);
      fail("Instantiated invalid ErasureCodingPolicy");
    } catch (IllegalArgumentException e) {
      GenericTestUtils.assertExceptionContains("cellSize", e);
    }
  }

  @Test
  public void testEqualsAndHashCode() {
    ErasureCodingPolicy[] policies = new ErasureCodingPolicy[]{
        new ErasureCodingPolicy("one", SCHEMA_1, 321, (byte) 1),
        new ErasureCodingPolicy("two", SCHEMA_1, 321, (byte) 1),
        new ErasureCodingPolicy("one", SCHEMA_2, 321, (byte) 1),
        new ErasureCodingPolicy("one", SCHEMA_1, 123, (byte) 1),
        new ErasureCodingPolicy("one", SCHEMA_1, 321, (byte) 3),
    };

    for (int i = 0; i < policies.length; i++) {
      final ErasureCodingPolicy ei = policies[i];
      // Check identity
      ErasureCodingPolicy temp = new ErasureCodingPolicy(ei.getName(), ei
          .getSchema(), ei.getCellSize(), ei.getId());
      assertEquals(ei, temp);
      assertEquals(ei.hashCode(), temp.hashCode());
      // Check against other policies
      for (int j = 0; j < policies.length; j++) {
        final ErasureCodingPolicy ej = policies[j];
        if (i == j) {
          assertEquals(ei, ej);
          assertEquals(ei.hashCode(), ej.hashCode());
        } else {
          assertNotEquals(ei, ej);
          assertNotEquals(ei, ej.hashCode());
        }
      }
    }
  }
}
