org.apache.avro.file.FileReader 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
*
* https://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.avro.file;
import java.io.IOException;
import java.io.Closeable;
import java.util.Iterator;
import java.util.NoSuchElementException;
import org.apache.avro.Schema;
/** Interface for reading data from a file. */
public interface FileReader extends Iterator, Iterable, Closeable {
/** Return the schema for data in this file. */
Schema getSchema();
/**
* Read the next datum from the file.
*
* @param reuse an instance to reuse.
* @throws NoSuchElementException if no more remain in the file.
*/
D next(D reuse) throws IOException;
/**
* Move to the next synchronization point after a position. To process a range
* of file entires, call this with the starting position, then check
* {@link #pastSync(long)} with the end point before each call to
* {@link #next()}.
*/
void sync(long position) throws IOException;
/** Return true if past the next synchronization point after a position. */
boolean pastSync(long position) throws IOException;
/** Return the current position in the input. */
long tell() throws IOException;
}