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'databene commons' is an open source Java library by Volker Bergmann.
It provides extensions to the Java core library by utility classes, abstract concepts
and concrete implementations.
/*
* Copyright (C) 2004-2015 Volker Bergmann ([email protected]).
* All rights reserved.
*
* 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.databene.commons.tree;
import org.databene.commons.Filter;
import org.databene.commons.TreeModel;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Logs the structure represented by a {@link org.databene.commons.TreeModel} implementor.
* Created: 10.11.2010 10:21:59
* @since 0.5.4
* @author Volker Bergmann
*/
public class TreeLogger {
private static final Logger LOGGER = LoggerFactory.getLogger(TreeLogger.class);
String indent = "";
// interface ---------------------------------------------------------------
public void log(TreeModel model) {
log(model.getRoot(), false, model, null);
}
public void log(TreeModel model, Filter filter) {
log(model.getRoot(), false, model, filter);
}
// private helper methods --------------------------------------------------
private void log(T node, boolean hasSiblings, TreeModel model, Filter filter) {
if (filter != null && !filter.accept(node))
return;
LOGGER.info(indent + node);
if (!model.isLeaf(node)) {
increaseIndent(hasSiblings);
int n = model.getChildCount(node);
for (int i = 0; i < n; i++)
log(model.getChild(node, i), i < n - 1, model, filter);
reduceIndent();
}
}
private void increaseIndent(boolean hasSuccessors) {
if (indent.length() == 0)
indent = "+-";
else if (hasSuccessors)
indent = indent.substring(0, indent.length() - 2) + "| " + indent.substring(indent.length() - 2);
else
indent = indent.substring(0, indent.length() - 2) + " " + indent.substring(indent.length() - 2);
}
private void reduceIndent() {
if (indent.length() >= 4)
indent = indent.substring(0, indent.length() - 4) + indent.substring(indent.length() - 2);
else
indent = "";
}
}