View Javadoc
1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.lang3.builder;
18  
19  import java.util.Collection;
20  
21  import org.apache.commons.lang3.ClassUtils;
22  
23  /**
24   * Works with {@link ToStringBuilder} to create a "deep" {@code toString}.
25   *
26   * <p>To use this class write code as follows:</p>
27   *
28   * <pre>
29   * public class Job {
30   *   String title;
31   *   ...
32   * }
33   *
34   * public class Person {
35   *   String name;
36   *   int age;
37   *   boolean smoker;
38   *   Job job;
39   *
40   *   ...
41   *
42   *   public String toString() {
43   *     return new ReflectionToStringBuilder(this, new RecursiveToStringStyle()).toString();
44   *   }
45   * }
46   * </pre>
47   *
48   * <p>This will produce a toString of the format:
49   * {@code Person@7f54[name=Stephen,age=29,smoker=false,job=Job@43cd2[title=Manager]]}</p>
50   *
51   * @since 3.2
52   */
53  public class RecursiveToStringStyle extends ToStringStyle {
54  
55      /**
56       * Required for serialization support.
57       *
58       * @see java.io.Serializable
59       */
60      private static final long serialVersionUID = 1L;
61  
62      /**
63       * Constructor.
64       */
65      public RecursiveToStringStyle() {
66      }
67  
68      /**
69       * Returns whether or not to recursively format the given {@link Class}.
70       * By default, this method always returns {@code true}, but may be overwritten by
71       * subclasses to filter specific classes.
72       *
73       * @param clazz
74       *            The class to test.
75       * @return Whether or not to recursively format the given {@link Class}.
76       */
77      protected boolean accept(final Class<?> clazz) {
78          return true;
79      }
80  
81      @Override
82      protected void appendDetail(final StringBuffer buffer, final String fieldName, final Collection<?> coll) {
83          appendClassName(buffer, coll);
84          appendIdentityHashCode(buffer, coll);
85          appendDetail(buffer, fieldName, coll.toArray());
86      }
87  
88      @Override
89      public void appendDetail(final StringBuffer buffer, final String fieldName, final Object value) {
90          if (!ClassUtils.isPrimitiveWrapper(value.getClass()) &&
91              !String.class.equals(value.getClass()) &&
92              accept(value.getClass())) {
93              buffer.append(ReflectionToStringBuilder.toString(value, this));
94          } else {
95              super.appendDetail(buffer, fieldName, value);
96          }
97      }
98  }