this patch decouples digester logging into an interface and a standard
implementation (that has the same functionality as the current digester
logging system). if the user wants to use a different logging system, then
they can simply create an implementation and set a property.
the cool thing about this approach is that it retains compatibility with
existing code whilst allow users to plug- in their own favourite logging
systems if they want to do so.
- robert
Index: digester/src/java/org/apache/commons/digester/Digester.java
===================================================================
RCS file:
/home/cvs/jakarta-commons/digester/src/java/org/apache/commons/digester/Digester.java,v
retrieving revision 1.13
diff -u -r1.13 Digester.java
--- digester/src/java/org/apache/commons/digester/Digester.java 2001/08/13 18:59:46
1.13
+++ digester/src/java/org/apache/commons/digester/Digester.java 2001/08/14 20:18:34
@@ -250,10 +250,9 @@
/**
- * The PrintWriter to which we should send log output, or
- * <code>null</code> to write to <code>System.out</code>.
+ * Used by digester for logging.
*/
- protected PrintWriter writer = null;
+ protected DigesterLogger logger = new BaseDigesterLogger();
// ----------------------------------------------------------- Properties
@@ -456,27 +455,69 @@
/**
- * Return the logging writer for this Digester.
+ * <p> Return the logging writer for this Digester.
+ *
+ * @deprecated Logging is now decoupled and need not use a
+<code>PrintWriter</code>
*/
public PrintWriter getWriter() {
-
- return (this.writer);
-
+ // yes, it's s bit of a hack
+ // but it's the neatest way to retain compatibility
+ if (logger instanceof BaseDigesterLogger)
+ {
+ return (((BaseDigesterLogger)logger).getWriter());
+ }
+ return null;
}
/**
- * Set the logging writer for this Digester.
+ * <p> Set the logging writer for this Digester.
+ * This method still works but is depricated.
*
* @param writer The new PrintWriter, or <code>null</code> for
* <code>System.out</code>.
+ * @deprecated Call {@link #setLogger} with a {@link BaseDigesterLogger} instead.
*/
public void setWriter(PrintWriter writer) {
-
- this.writer = writer;
+ // yes, it's s bit of a hack
+ // but it's the neatest way to retain compatibility
+ if (logger instanceof BaseDigesterLogger)
+ {
+
+ ((BaseDigesterLogger)logger).setWriter(writer);
+
+ } else {
+
+ setLogger(new BaseDigesterLogger(writer));
+
+ }
+ }
+ /**
+ * <p> Get the logger for this Digester.
+ *
+ * <p> {@link DigesterLogger} decouples logging.
+ * {@link BaseDigesterLogger} is the default implementation
+ * and has the same functionality as the original digester logging system.
+ */
+ public DigesterLogger getLogger()
+ {
+ return logger;
}
+ /**
+ * <p> Set the logger for this Digester.
+ *
+ * <p> {@link DigesterLogger} decouples logging.
+ * {@link BaseDigesterLogger} is the default implementation
+ * and has the same functionality as the original digester logging system.
+ *
+ * @param logger the new logger or <code>null</code> to disable logging
+ */
+ public void setLogger(DigesterLogger logger)
+ {
+ this.logger=logger;
+ }
/**
* Return the boolean as to whether the context classloader should be used.
@@ -897,36 +938,37 @@
/**
- * Log a message to the log writer associated with this context.
+ * Log a message and associated exception.
+ * Log to the {@link DigesterLogger}
+ * associated with this digester.
*
* @param message The message to be logged
*/
public void log(String message) {
-
- if (writer == null)
- System.out.println(message);
- else
- writer.println(message);
-
+ // support null loggers
+ if (logger!=null)
+ {
+ logger.log(message);
+ }
}
/**
- * Log a message and associated exception to the log writer
- * associated with this context.
+ * Log a message and associated exception.
+ * Log to the {@link DigesterLogger}
+ * associated with this digester.
*
* @param message The message to be logged
* @param exception The associated exception to be logged
*/
public void log(String message, Throwable exception) {
- if (writer == null) {
- System.out.println(message);
- exception.printStackTrace(System.out);
- } else {
- writer.println(message);
- exception.printStackTrace(writer);
+ // support null loggers
+ if (logger!=null)
+ {
+ logger.log(message,exception);
}
+
}
DigesterLogger.java
BaseDigesterLogger.java
