FileHandler


1   /*
2    * Copyright 1999-2005 The Apache Software Foundation.
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.jboss.logging.jdk.handlers;
17  
18  import java.io.IOException  ;
19  import java.io.FileOutputStream  ;
20  import java.io.FileNotFoundException  ;
21  import java.io.File  ;
22  import java.io.Writer  ;
23  import java.io.BufferedWriter  ;
24  import java.util.logging.Formatter  ;
25  import java.util.logging.ErrorManager  ;
26  
27  /**
28   *  FileAppender appends log events to a file.
29   *
30   * @author Ceki G&uuml;lc&uuml; 
31   * @author Scott.Stark@jboss.org
32   * @version $Revision: 1958 $
33   */
34  public class FileHandler extends WriterHandler
35  {
36     /**
37      * Controls file truncatation. The default value for this variable
38      * is <code>true</code>, meaning that by default a
39      * <code>FileAppender</code> will append to an existing file and not
40      * truncate it.
41      * <p/>
42      * <p>This option is meaningful only if the FileAppender opens the
43      * file.
44      */
45     protected boolean fileAppend = true;
46  
47     /**
48      * The name of the log file.
49      */
50     protected String   fileName = null;
51  
52     /**
53      * The default constructor does not do anything.
54      */
55     public FileHandler()
56     {
57     }
58  
59     /**
60      * Instantiate a <code>FileHandler</code> and open the file
61      * designated by <code>filename</code>. The opened filename will
62      * become the output destination for this appender.
63      * <p/>
64      * <p>If the <code>append</code> parameter is true, the file will be
65      * appended to. Otherwise, the file designated by
66      * <code>filename</code> will be truncated before being opened.
67      * <p/>
68      * <p>If the <code>bufferedIO</code> parameter is <code>true</code>,
69      * then buffered IO will be used to write to the output file.
70      */
71     public FileHandler(Formatter   layout, String   filename, boolean append, boolean bufferedIO,
72        int bufferSize)
73        throws IOException  
74     {
75        super.setFormatter(layout);
76        this.setFile(filename, append, bufferedIO, bufferSize);
77     }
78  
79     /**
80      * Instantiate a FileHandler and open the file designated by
81      * <code>filename</code>. The opened filename will become the output
82      * destination for this appender.
83      * <p/>
84      * <p>If the <code>append</code> parameter is true, the file will be
85      * appended to. Otherwise, the file designated by
86      * <code>filename</code> will be truncated before being opened.
87      */
88     public FileHandler(Formatter   layout, String   filename, boolean append)
89        throws IOException  
90     {
91        this(layout, filename, append, true, 2048);
92     }
93  
94     /**
95      * Instantiate a FileHandler and open the file designated by
96      * <code>filename</code>. The opened filename will become the output
97      * destination for this appender.
98      * <p/>
99      * <p>The file will be appended to.
100     */
101    public FileHandler(Formatter   layout, String   filename) throws IOException  
102    {
103       this(layout, filename, true);
104    }
105 
106    /**
107     * The <b>File</b> property takes a string value which should be the
108     * name of the file to append to.
109     * <p/>
110     * <p>Note: Actual opening of the file is made when {@link
111     * #activateOptions} is called, not when the options are set.
112     */
113    public void setFile(String   file)
114    {
115       // Trim spaces from both ends. The users probably does not want
116       // trailing spaces in file names.
117       String   val = file.trim();
118       fileName = val;
119    }
120 
121    /**
122     * Returns the value of the <b>Append</b> option.
123     */
124    public boolean getAppend()
125    {
126       return fileAppend;
127    }
128 
129 
130    /**
131     * Returns the value of the <b>File</b> option.
132     */
133    public String   getFile()
134    {
135       return fileName;
136    }
137 
138    /**
139     * If the value of <b>File</b> is not <code>null</code>, then {@link
140     * #setFile} is called with the values of <b>File</b>  and
141     * <b>Append</b> properties.
142     *
143     */
144    public void activateOptions()
145    {
146       if (fileName != null)
147       {
148          try
149          {
150             setFile(fileName, fileAppend, bufferedIO, bufferSize);
151          }
152          catch (java.io.IOException   e)
153          {
154             reportError("setFile(" + fileName + "," + fileAppend + ") call failed.",
155                e, ErrorManager.OPEN_FAILURE);
156          }
157       }
158       else
159       {
160          reportError("File option not set for appender [" + name + "]."
161             +" Are you using FileHandler instead of ConsoleAppender?",
162             null, ErrorManager.OPEN_FAILURE);
163       }
164    }
165 
166    /**
167     * The <b>Append</b> option takes a boolean value. It is set to
168     * <code>true</code> by default. If true, then <code>File</code>
169     * will be opened in append mode by {@link #setFile setFile} (see
170     * above). Otherwise, {@link #setFile setFile} will open
171     * <code>File</code> in truncate mode.
172     * <p/>
173     * <p>Note: Actual opening of the file is made when {@link
174     * #activateOptions} is called, not when the options are set.
175     */
176    public void setAppend(boolean flag)
177    {
178       fileAppend = flag;
179    }
180 
181    /**
182     * <p>Sets and <i>opens</i> the file where the log output will
183     * go. The specified file must be writable.
184     * <p/>
185     * <p>If there was already an opened file, then the previous file
186     * is closed first.
187     * <p/>
188     * <p><b>Do not use this method directly. To configure a FileHandler
189     * or one of its subclasses, set its properties one by one and then
190     * call activateOptions.</b>
191     *
192     * @param fileName The path to the log file.
193     * @param append   If true will append to fileName. Otherwise will
194     *                 truncate fileName.
195     */
196    public synchronized void setFile(String   fileName, boolean append, boolean bufferedIO, int bufferSize)
197       throws IOException  
198    {
199 //      reportError("setFile called: " + fileName + ", " + append, null, ErrorManager.GENERIC_FAILURE);
200       super.setBufferedIO(bufferedIO);
201       super.setBufferSize(bufferSize);
202       FileOutputStream   ostream = null;
203       try
204       {
205          //   attempt to create file
206          ostream = new FileOutputStream  (fileName, append);
207       }
208       catch (FileNotFoundException   ex)
209       {
210          //   if parent directory does not exist then
211          //      attempt to create it and try to create file
212          String   parentName = new File  (fileName).getParent();
213          if (parentName != null)
214          {
215             File   parentDir = new File  (parentName);
216             if (!parentDir.exists() && parentDir.mkdirs())
217             {
218                ostream = new FileOutputStream  (fileName, append);
219             }
220             else
221             {
222                throw ex;
223             }
224          }
225          else
226          {
227             throw ex;
228          }
229       }
230       super.setOutputStream(ostream);
231       this.fileName = fileName;
232       this.fileAppend = append;
233       // LogLog.debug("setFile ended");
234    }
235 
236 }
237 
238
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