1 /*
2 * Copyright 2007 Kasper B. Graversen
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 package org.supercsv.io;
17
18 import java.io.Closeable;
19 import java.io.IOException;
20
21 import org.supercsv.exception.SuperCsvException;
22
23 /**
24 * The interface for CSV readers.
25 *
26 * @author Kasper B. Graversen
27 * @author James Bassett
28 */
29 public interface ICsvReader extends Closeable {
30
31 /**
32 * Get column N of the current line (column indexes begin at 1).
33 *
34 * @param n
35 * the index of the column to get
36 * @return the n'th column
37 * @throws IndexOutOfBoundsException
38 * if the supplied index is not a valid column index
39 * @since 1.0
40 */
41 String get(int n);
42
43 /**
44 * This method is used to get an optional header of the CSV file and move the file cursor to the first row
45 * containing data (the second row from the top). The header can subsequently be used as the
46 * <code>nameMapping</code> array for read operations.
47 *
48 * @param firstLineCheck
49 * if true, ensures that this method is only called when reading the first line (as that's where the
50 * header is meant to be)
51 * @return the array of header fields, or null if EOF is encountered
52 * @throws IOException
53 * if an I/O exception occurs
54 * @throws SuperCsvException
55 * if firstLineCheck == true and it's not the first line being read
56 * @since 1.0
57 */
58 String[] getHeader(boolean firstLineCheck) throws IOException;
59
60 /**
61 * Gets the current position in the file, where the first line of the file is line number 1.
62 *
63 * @return the line number
64 * @since 1.0
65 */
66 int getLineNumber();
67
68 /**
69 * Returns the untokenized CSV row that was just read (which can potentially span multiple lines in the file).
70 *
71 * @return the untokenized CSV row that was just read
72 * @since 2.0.0
73 */
74 String getUntokenizedRow();
75
76 /**
77 * Gets the current row number (i.e. the number of CSV records - including the header - that have been read). This
78 * differs from the lineNumber, which is the number of real lines that have been read in the file. The first row is
79 * row 1 (which is typically the header row).
80 *
81 * @return the current row number
82 * @since 2.0.0
83 */
84 int getRowNumber();
85
86 /**
87 * Returns the length (i.e. number of columns) of the current row.
88 *
89 * @return the length of the current row
90 * @since 1.0
91 */
92 int length();
93
94 }