| 1 | /* |
| 2 | * Copyright (C) Christian Schulte, 2005-206 |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * |
| 9 | * o Redistributions of source code must retain the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer. |
| 11 | * |
| 12 | * o Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in |
| 14 | * the documentation and/or other materials provided with the |
| 15 | * distribution. |
| 16 | * |
| 17 | * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
| 18 | * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY |
| 19 | * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
| 20 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | * |
| 28 | * $JOMC: LineEditor.java 4613 2012-09-22 10:07:08Z schulte $ |
| 29 | * |
| 30 | */ |
| 31 | package org.jomc.util; |
| 32 | |
| 33 | import java.io.BufferedReader; |
| 34 | import java.io.IOException; |
| 35 | import java.io.StringReader; |
| 36 | |
| 37 | /** |
| 38 | * Interface to line based editing. |
| 39 | * |
| 40 | * @author <a href="mailto:cs@schulte.it">Christian Schulte</a> |
| 41 | * @version $JOMC: LineEditor.java 4613 2012-09-22 10:07:08Z schulte $ |
| 42 | * |
| 43 | * @see #edit(java.lang.String) |
| 44 | */ |
| 45 | public class LineEditor |
| 46 | { |
| 47 | |
| 48 | /** Editor to chain. */ |
| 49 | private LineEditor editor; |
| 50 | |
| 51 | /** Line separator. */ |
| 52 | private String lineSeparator; |
| 53 | |
| 54 | /** |
| 55 | * Current line number. |
| 56 | * @since 1.2 |
| 57 | */ |
| 58 | private long lineNumber; |
| 59 | |
| 60 | /** Creates a new {@code LineEditor} instance. */ |
| 61 | public LineEditor() |
| 62 | { |
| 63 | this( null, null ); |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * Creates a new {@code LineEditor} instance taking a string to use for separating lines. |
| 68 | * |
| 69 | * @param lineSeparator String to use for separating lines. |
| 70 | */ |
| 71 | public LineEditor( final String lineSeparator ) |
| 72 | { |
| 73 | this( null, lineSeparator ); |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Creates a new {@code LineEditor} instance taking an editor to chain. |
| 78 | * |
| 79 | * @param editor The editor to chain. |
| 80 | */ |
| 81 | public LineEditor( final LineEditor editor ) |
| 82 | { |
| 83 | this( editor, null ); |
| 84 | } |
| 85 | |
| 86 | /** |
| 87 | * Creates a new {@code LineEditor} instance taking an editor to chain and a string to use for separating lines. |
| 88 | * |
| 89 | * @param editor The editor to chain. |
| 90 | * @param lineSeparator String to use for separating lines. |
| 91 | */ |
| 92 | public LineEditor( final LineEditor editor, final String lineSeparator ) |
| 93 | { |
| 94 | super(); |
| 95 | this.editor = editor; |
| 96 | this.lineSeparator = lineSeparator; |
| 97 | this.lineNumber = 0L; |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * Gets the line separator of the editor. |
| 102 | * |
| 103 | * @return The line separator of the editor. |
| 104 | */ |
| 105 | public final String getLineSeparator() |
| 106 | { |
| 107 | if ( this.lineSeparator == null ) |
| 108 | { |
| 109 | this.lineSeparator = System.getProperty( "line.separator", "\n" ); |
| 110 | } |
| 111 | |
| 112 | return this.lineSeparator; |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * Gets the current line number. |
| 117 | * |
| 118 | * @return The current line number. |
| 119 | * |
| 120 | * @since 1.2 |
| 121 | */ |
| 122 | public final long getLineNumber() |
| 123 | { |
| 124 | return this.lineNumber; |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * Edits text. |
| 129 | * <p>This method splits the given string into lines and passes every line to method {@code editLine} in order of |
| 130 | * occurrence. On end of input, method {@code editLine} is called with a {@code null} argument.</p> |
| 131 | * |
| 132 | * @param text The text to edit or {@code null}. |
| 133 | * |
| 134 | * @return The edited text or {@code null}. |
| 135 | * |
| 136 | * @throws IOException if editing fails. |
| 137 | */ |
| 138 | public final String edit( final String text ) throws IOException |
| 139 | { |
| 140 | String edited = text; |
| 141 | this.lineNumber = 0L; |
| 142 | BufferedReader reader = null; |
| 143 | boolean suppressExceptionOnClose = true; |
| 144 | |
| 145 | try |
| 146 | { |
| 147 | if ( edited != null ) |
| 148 | { |
| 149 | final StringBuilder buf = new StringBuilder( edited.length() + 16 ); |
| 150 | boolean appended = false; |
| 151 | |
| 152 | if ( edited.length() > 0 ) |
| 153 | { |
| 154 | reader = new BufferedReader( new StringReader( edited ) ); |
| 155 | |
| 156 | String line = null; |
| 157 | while ( ( line = reader.readLine() ) != null ) |
| 158 | { |
| 159 | this.lineNumber++; |
| 160 | final String replacement = this.editLine( line ); |
| 161 | if ( replacement != null ) |
| 162 | { |
| 163 | buf.append( replacement ).append( this.getLineSeparator() ); |
| 164 | appended = true; |
| 165 | } |
| 166 | } |
| 167 | } |
| 168 | else |
| 169 | { |
| 170 | this.lineNumber++; |
| 171 | final String replacement = this.editLine( edited ); |
| 172 | if ( replacement != null ) |
| 173 | { |
| 174 | buf.append( replacement ).append( this.getLineSeparator() ); |
| 175 | appended = true; |
| 176 | } |
| 177 | } |
| 178 | |
| 179 | final String replacement = this.editLine( null ); |
| 180 | if ( replacement != null ) |
| 181 | { |
| 182 | buf.append( replacement ); |
| 183 | appended = true; |
| 184 | } |
| 185 | |
| 186 | edited = appended ? buf.toString() : null; |
| 187 | } |
| 188 | |
| 189 | if ( this.editor != null ) |
| 190 | { |
| 191 | edited = this.editor.edit( edited ); |
| 192 | } |
| 193 | |
| 194 | suppressExceptionOnClose = false; |
| 195 | return edited; |
| 196 | } |
| 197 | finally |
| 198 | { |
| 199 | try |
| 200 | { |
| 201 | if ( reader != null ) |
| 202 | { |
| 203 | reader.close(); |
| 204 | } |
| 205 | } |
| 206 | catch ( final IOException e ) |
| 207 | { |
| 208 | if ( !suppressExceptionOnClose ) |
| 209 | { |
| 210 | throw e; |
| 211 | } |
| 212 | } |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | /** |
| 217 | * Edits a line. |
| 218 | * |
| 219 | * @param line The line to edit or {@code null}, indicating the end of input. |
| 220 | * |
| 221 | * @return The string to replace {@code line} with or {@code null}, to replace {@code line} with nothing. |
| 222 | * |
| 223 | * @throws IOException if editing fails. |
| 224 | */ |
| 225 | protected String editLine( final String line ) throws IOException |
| 226 | { |
| 227 | return line; |
| 228 | } |
| 229 | |
| 230 | } |