/*
 * 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.hbase.util;

import java.io.InterruptedIOException;
import java.net.SocketTimeoutException;
import java.nio.channels.ClosedByInterruptException;
import org.apache.yetus.audience.InterfaceAudience;

/**
 * This class handles the different interruption classes. It can be: - InterruptedException -
 * InterruptedIOException (inherits IOException); used in IO - ClosedByInterruptException (inherits
 * IOException) - SocketTimeoutException inherits InterruptedIOException but is not a real
 * interruption, so we have to distinguish the case. This pattern is unfortunately common.
 */
@InterfaceAudience.Private
public final class ExceptionUtil {
  private ExceptionUtil() {
  }

  /** Returns true if the throwable comes an interruption, false otherwise. */
  public static boolean isInterrupt(Throwable t) {
    if (t instanceof InterruptedException) {
      return true;
    }

    if (t instanceof SocketTimeoutException) {
      return false;
    }

    return (t instanceof InterruptedIOException || t instanceof ClosedByInterruptException);
  }

  /** Throw InterruptedIOException if t was an interruption, nothing otherwise. */
  public static void rethrowIfInterrupt(Throwable t) throws InterruptedIOException {
    InterruptedIOException iie = asInterrupt(t);

    if (iie != null) {
      throw iie;
    }
  }

  /** Returns an InterruptedIOException if t was an interruption, null otherwise */
  public static InterruptedIOException asInterrupt(Throwable t) {
    if (t instanceof SocketTimeoutException) {
      return null;
    }

    if (t instanceof InterruptedIOException) {
      return (InterruptedIOException) t;
    }

    if (t instanceof InterruptedException || t instanceof ClosedByInterruptException) {
      InterruptedIOException iie =
        new InterruptedIOException("Origin: " + t.getClass().getSimpleName());
      iie.initCause(t);
      return iie;
    }

    return null;
  }
}
