1// Protocol Buffers - Google's data interchange format
2// Copyright 2008 Google Inc.  All rights reserved.
3// http://code.google.com/p/protobuf/
4//
5// Redistribution and use in source and binary forms, with or without
6// modification, are permitted provided that the following conditions are
7// met:
8//
9//     * Redistributions of source code must retain the above copyright
10// notice, this list of conditions and the following disclaimer.
11//     * Redistributions in binary form must reproduce the above
12// copyright notice, this list of conditions and the following disclaimer
13// in the documentation and/or other materials provided with the
14// distribution.
15//     * Neither the name of Google Inc. nor the names of its
16// contributors may be used to endorse or promote products derived from
17// this software without specific prior written permission.
18//
19// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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29// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31package com.google.protobuf;
32
33import java.util.Collections;
34import java.util.List;
35
36/**
37 * Thrown when attempting to build a protocol message that is missing required
38 * fields.  This is a {@code RuntimeException} because it normally represents
39 * a programming error:  it happens when some code which constructs a message
40 * fails to set all the fields.  {@code parseFrom()} methods <b>do not</b>
41 * throw this; they throw an {@link InvalidProtocolBufferException} if
42 * required fields are missing, because it is not a programming error to
43 * receive an incomplete message.  In other words,
44 * {@code UninitializedMessageException} should never be thrown by correct
45 * code, but {@code InvalidProtocolBufferException} might be.
46 *
47 * @author kenton@google.com Kenton Varda
48 */
49public class UninitializedMessageException extends RuntimeException {
50  private static final long serialVersionUID = -7466929953374883507L;
51
52  public UninitializedMessageException(final MessageLite message) {
53    super("Message was missing required fields.  (Lite runtime could not " +
54          "determine which fields were missing).");
55    missingFields = null;
56  }
57
58  public UninitializedMessageException(final List<String> missingFields) {
59    super(buildDescription(missingFields));
60    this.missingFields = missingFields;
61  }
62
63  private final List<String> missingFields;
64
65  /**
66   * Get a list of human-readable names of required fields missing from this
67   * message.  Each name is a full path to a field, e.g. "foo.bar[5].baz".
68   * Returns null if the lite runtime was used, since it lacks the ability to
69   * find missing fields.
70   */
71  public List<String> getMissingFields() {
72    return Collections.unmodifiableList(missingFields);
73  }
74
75  /**
76   * Converts this exception to an {@link InvalidProtocolBufferException}.
77   * When a parsed message is missing required fields, this should be thrown
78   * instead of {@code UninitializedMessageException}.
79   */
80  public InvalidProtocolBufferException asInvalidProtocolBufferException() {
81    return new InvalidProtocolBufferException(getMessage());
82  }
83
84  /** Construct the description string for this exception. */
85  private static String buildDescription(final List<String> missingFields) {
86    final StringBuilder description =
87      new StringBuilder("Message missing required fields: ");
88    boolean first = true;
89    for (final String field : missingFields) {
90      if (first) {
91        first = false;
92      } else {
93        description.append(", ");
94      }
95      description.append(field);
96    }
97    return description.toString();
98  }
99}
100