001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.pool2;
018
019/**
020 * A base class for common functionality.
021 *
022 * @since 2.4.3
023 */
024public abstract class BaseObject {
025
026    @Override
027    public String toString() {
028        final StringBuilder builder = new StringBuilder();
029        builder.append(getClass().getSimpleName());
030        builder.append(" [");
031        toStringAppendFields(builder);
032        builder.append("]");
033        return builder.toString();
034    }
035
036    /**
037     * Used by sub-classes to include the fields defined by the sub-class in the
038     * {@link #toString()} output.
039     *
040     * @param builder Field names and values are appended to this object
041     */
042    protected void toStringAppendFields(final StringBuilder builder) {
043        // do nothing by default, needed for b/w compatibility.
044    }
045}