001package org.apache.maven.settings.building;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 *
012 *   http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022/**
023 * Describes a problem that was encountered during settings building. A problem can either be an exception that was
024 * thrown or a simple string message. In addition, a problem carries a hint about its source, e.g. the settings file
025 * that exhibits the problem.
026 * 
027 * @author Benjamin Bentmann
028 */
029public interface SettingsProblem
030{
031
032    /**
033     * The different severity levels for a problem, in decreasing order.
034     */
035    enum Severity
036    {
037
038        FATAL, //
039        ERROR, //
040        WARNING //
041
042    }
043
044    /**
045     * Gets the hint about the source of the problem. While the syntax of this hint is unspecified and depends on the
046     * creator of the problem, the general expectation is that the hint provides sufficient information to the user to
047     * track the problem back to its origin. A concrete example for such a source hint can be the file path or URL from
048     * which the settings were read.
049     * 
050     * @return The hint about the source of the problem or an empty string if unknown, never {@code null}.
051     */
052    String getSource();
053
054    /**
055     * Gets the one-based index of the line containing the problem. The line number should refer to some text file that
056     * is given by {@link #getSource()}.
057     * 
058     * @return The one-based index of the line containing the problem or a non-positive value if unknown.
059     */
060    int getLineNumber();
061
062    /**
063     * Gets the one-based index of the column containing the problem. The column number should refer to some text file
064     * that is given by {@link #getSource()}.
065     * 
066     * @return The one-based index of the column containing the problem or non-positive value if unknown.
067     */
068    int getColumnNumber();
069
070    /**
071     * Gets the location of the problem. The location is a user-friendly combination of the values from
072     * {@link #getSource()}, {@link #getLineNumber()} and {@link #getColumnNumber()}. The exact syntax of the returned
073     * value is undefined.
074     * 
075     * @return The location of the problem, never {@code null}.
076     */
077    String getLocation();
078
079    /**
080     * Gets the exception that caused this problem (if any).
081     * 
082     * @return The exception that caused this problem or {@code null} if not applicable.
083     */
084    Exception getException();
085
086    /**
087     * Gets the message that describes this problem.
088     * 
089     * @return The message describing this problem, never {@code null}.
090     */
091    String getMessage();
092
093    /**
094     * Gets the severity level of this problem.
095     * 
096     * @return The severity level of this problem, never {@code null}.
097     */
098    Severity getSeverity();
099
100}