1   /*
2    * Copyright (C) 2009 The Guava Authors
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    * http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package com.google.common.io;
18  
19  import com.google.common.annotations.Beta;
20  
21  import java.io.IOException;
22  
23  /**
24   * A callback to be used with the streaming {@code readLines} methods.
25   *
26   * <p>{@link #processLine} will be called for each line that is read, and
27   * should return {@code false} when you want to stop processing.
28   *
29   * @author Miles Barr
30   * @since 1.0
31   */
32  @Beta
33  public interface LineProcessor<T> {
34  
35    /**
36     * This method will be called once for each line.
37     *
38     * @param line the line read from the input, without delimiter
39     * @return true to continue processing, false to stop
40     */
41    boolean processLine(String line) throws IOException;
42  
43    /** Return the result of processing all the lines. */
44    T getResult();
45  }