1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.maven.model.building;
20
21 import java.io.PrintWriter;
22 import java.io.StringWriter;
23 import java.util.Collections;
24 import java.util.List;
25
26 import org.apache.maven.model.Model;
27
28 /**
29 * Signals one ore more errors during model building. The model builder tries to collect as many problems as possible
30 * before eventually failing to provide callers with rich error information. Use {@link #getProblems()} to query the
31 * details of the failure.
32 *
33 * @author Benjamin Bentmann
34 */
35 public class ModelBuildingException extends Exception {
36
37 private final ModelBuildingResult result;
38
39 /**
40 * Creates a new exception with the specified problems.
41 *
42 * @param model The model that could not be built, may be {@code null}.
43 * @param modelId The identifier of the model that could not be built, may be {@code null}.
44 * @param problems The problems that causes this exception, may be {@code null}.
45 * @deprecated Use {@link #ModelBuildingException(ModelBuildingResult)} instead.
46 */
47 @Deprecated
48 public ModelBuildingException(Model model, String modelId, List<ModelProblem> problems) {
49 super(toMessage(modelId, problems));
50
51 if (model != null) {
52 DefaultModelBuildingResult tmp = new DefaultModelBuildingResult();
53 if (modelId == null) {
54 modelId = "";
55 }
56 tmp.addModelId(modelId);
57 tmp.setRawModel(modelId, model);
58 tmp.setProblems(problems);
59 result = tmp;
60 } else {
61 result = null;
62 }
63 }
64
65 /**
66 * Creates a new exception from the specified interim result and its associated problems.
67 *
68 * @param result The interim result, may be {@code null}.
69 */
70 public ModelBuildingException(ModelBuildingResult result) {
71 super(toMessage(result));
72 this.result = result;
73 }
74
75 /**
76 * Gets the interim result of the model building up to the point where it failed.
77 *
78 * @return The interim model building result or {@code null} if not available.
79 */
80 public ModelBuildingResult getResult() {
81 return result;
82 }
83
84 /**
85 * Gets the model that could not be built properly.
86 *
87 * @return The erroneous model or {@code null} if not available.
88 */
89 public Model getModel() {
90 if (result == null) {
91 return null;
92 }
93 if (result.getEffectiveModel() != null) {
94 return result.getEffectiveModel();
95 }
96 return result.getRawModel();
97 }
98
99 /**
100 * Gets the identifier of the POM whose effective model could not be built. The general format of the identifier is
101 * {@code <groupId>:<artifactId>:<version>} but some of these coordinates may still be unknown at the point the
102 * exception is thrown so this information is merely meant to assist the user.
103 *
104 * @return The identifier of the POM or an empty string if not known, never {@code null}.
105 */
106 public String getModelId() {
107 if (result == null || result.getModelIds().isEmpty()) {
108 return "";
109 }
110 return result.getModelIds().get(0);
111 }
112
113 /**
114 * Gets the problems that caused this exception.
115 *
116 * @return The problems that caused this exception, never {@code null}.
117 */
118 public List<ModelProblem> getProblems() {
119 if (result == null) {
120 return Collections.emptyList();
121 }
122 return Collections.unmodifiableList(result.getProblems());
123 }
124
125 private static String toMessage(ModelBuildingResult result) {
126 if (result != null && !result.getModelIds().isEmpty()) {
127 return toMessage(result.getModelIds().get(0), result.getProblems());
128 }
129 return null;
130 }
131
132 private static String toMessage(String modelId, List<ModelProblem> problems) {
133 StringWriter buffer = new StringWriter(1024);
134
135 PrintWriter writer = new PrintWriter(buffer);
136
137 writer.print(problems.size());
138 writer.print((problems.size() == 1) ? " problem was " : " problems were ");
139 writer.print("encountered while building the effective model");
140 if (modelId != null && modelId.length() > 0) {
141 writer.print(" for ");
142 writer.print(modelId);
143 }
144 writer.println();
145
146 for (ModelProblem problem : problems) {
147 writer.print("[");
148 writer.print(problem.getSeverity());
149 writer.print("] ");
150 writer.print(problem.getMessage());
151 writer.print(" @ ");
152 writer.println(ModelProblemUtils.formatLocation(problem, modelId));
153 }
154
155 return buffer.toString();
156 }
157 }