org.apache.hadoop.hdfs.ExceptionLastSeen Maven / Gradle / Ivy
/**
* 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;
import org.apache.hadoop.classification.InterfaceAudience;
import java.io.IOException;
import java.nio.channels.ClosedChannelException;
/**
* The exception last seen by the {@link DataStreamer} or
* {@link DFSOutputStream}.
*/
@InterfaceAudience.Private
class ExceptionLastSeen {
private IOException thrown;
/** Get the last seen exception. */
synchronized protected IOException get() {
return thrown;
}
/**
* Set the last seen exception.
* @param t the exception.
*/
synchronized void set(Throwable t) {
assert t != null;
this.thrown = t instanceof IOException ?
(IOException) t : new IOException(t);
}
/** Clear the last seen exception. */
synchronized void clear() {
thrown = null;
}
/**
* Check if there already is an exception. Throw the exception if exist.
*
* @param resetToNull set to true to reset exception to null after calling
* this function.
* @throws IOException on existing IOException.
*/
synchronized void check(boolean resetToNull) throws IOException {
if (thrown != null) {
final IOException e = thrown;
if (resetToNull) {
thrown = null;
}
throw e;
}
}
synchronized void throwException4Close() throws IOException {
check(false);
throw new ClosedChannelException();
}
}