| /** |
| * 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.apex.malhar.sql.operators; |
| |
| import java.io.BufferedReader; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InputStreamReader; |
| |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.fs.Path; |
| |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.lib.io.fs.AbstractFileInputOperator; |
| |
| /** |
| * This operator reads data from given file/folder in line by line fashion. |
| * |
| * @since 3.6.0 |
| */ |
| @InterfaceStability.Evolving |
| public class LineReader extends AbstractFileInputOperator<byte[]> |
| { |
| public final transient DefaultOutputPort<byte[]> output = new DefaultOutputPort<>(); |
| |
| protected transient BufferedReader br; |
| |
| @Override |
| protected InputStream openFile(Path path) throws IOException |
| { |
| InputStream is = super.openFile(path); |
| br = new BufferedReader(new InputStreamReader(is)); |
| return is; |
| } |
| |
| @Override |
| protected void closeFile(InputStream is) throws IOException |
| { |
| super.closeFile(is); |
| br.close(); |
| br = null; |
| } |
| |
| @Override |
| protected byte[] readEntity() throws IOException |
| { |
| String s = br.readLine(); |
| if (s != null) { |
| return s.getBytes(); |
| } |
| return null; |
| } |
| |
| @Override |
| protected void emit(byte[] tuple) |
| { |
| output.emit(tuple); |
| } |
| } |