| // Copyright 2006, 2007, 2008 The Apache Software Foundation |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package org.apache.tapestry5.ioc.internal.services; |
| |
| import org.apache.tapestry5.ioc.Invocation; |
| import org.apache.tapestry5.ioc.services.ExceptionTracker; |
| import org.slf4j.Logger; |
| |
| import static java.lang.String.format; |
| import java.util.Iterator; |
| |
| /** |
| * Used by {@link org.apache.tapestry5.ioc.internal.services.LoggingDecoratorImpl} to delegate out logging behavior to a |
| * seperate object. |
| */ |
| public final class MethodLogger |
| { |
| private static final int BUFFER_SIZE = 200; |
| |
| private static final String ENTER = "ENTER"; |
| |
| private static final String EXIT = " EXIT"; |
| |
| private static final String FAIL = " FAIL"; |
| |
| private final Logger logger; |
| |
| private final ExceptionTracker exceptionTracker; |
| |
| public MethodLogger(Logger logger, ExceptionTracker exceptionTracker) |
| { |
| this.logger = logger; |
| this.exceptionTracker = exceptionTracker; |
| } |
| |
| public boolean isDebugEnabled() |
| { |
| return logger.isDebugEnabled(); |
| } |
| |
| /** |
| * Invoked when a method is first entered |
| * |
| * @param invocation identifies method invoked as well as parameters passed to method |
| */ |
| public void entry(Invocation invocation) |
| { |
| StringBuilder buffer = new StringBuilder(BUFFER_SIZE); |
| |
| buffer.append(format("[%s] %s(", ENTER, invocation.getMethodName())); |
| |
| for (int i = 0; i < invocation.getParameterCount(); i++) |
| { |
| if (i > 0) buffer.append(", "); |
| |
| convert(buffer, invocation.getParameter(i)); |
| } |
| |
| buffer.append(")"); |
| |
| logger.debug(buffer.toString()); |
| } |
| |
| private void convert(StringBuilder buffer, Object object) |
| { |
| if (object == null) |
| { |
| buffer.append("null"); |
| return; |
| } |
| |
| // Minimal, alas: Doesn't handle embedded quotes and other |
| // characters. Really want to convert the string back to what it |
| // would look like as source code. |
| |
| if (object instanceof String) |
| { |
| buffer.append("\""); |
| buffer.append(object.toString()); |
| buffer.append("\""); |
| return; |
| } |
| |
| if (object instanceof Object[]) |
| { |
| Object[] values = (Object[]) object; |
| buffer.append('{'); |
| |
| for (int i = 0; i < values.length; i++) |
| { |
| if (i > 0) buffer.append(", "); |
| |
| convert(buffer, values[i]); |
| } |
| |
| buffer.append('}'); |
| return; |
| } |
| |
| if (object instanceof Iterable) |
| { |
| Iterable itr = (Iterable) object; |
| boolean first = true; |
| |
| buffer.append('['); |
| Iterator i = itr.iterator(); |
| while (i.hasNext()) |
| { |
| if (!first) buffer.append(", "); |
| |
| convert(buffer, i.next()); |
| first = false; |
| } |
| buffer.append(']'); |
| return; |
| } |
| |
| // Might need to add a few more, for things like character values ... |
| |
| buffer.append(object.toString()); |
| } |
| |
| /** |
| * Invoked when a method exits (possibly returning a value). |
| * |
| * @param invocation identifies method invocation and result value |
| */ |
| public void exit(Invocation invocation) |
| { |
| StringBuilder buffer = new StringBuilder(BUFFER_SIZE); |
| |
| buffer.append(format("[%s] %s", EXIT, invocation.getMethodName())); |
| |
| if (invocation.getResultType() != void.class) |
| { |
| buffer.append(" ["); |
| convert(buffer, invocation.getResult()); |
| buffer.append(']'); |
| } |
| |
| logger.debug(buffer.toString()); |
| } |
| |
| /** |
| * Invoked when method invocation instead throws an exception. |
| * |
| * @param invocation identifies method invocation which failed |
| * @param t exception throws by method invocation |
| */ |
| public void fail(Invocation invocation, Throwable t) |
| { |
| logger.debug( |
| format("[%s] %s -- %s", FAIL, |
| invocation.getMethodName(), |
| t.getClass().getName()), |
| exceptionTracker.exceptionLogged(t) ? null : t); |
| } |
| } |